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WO1986007351A1 - Method and catalyst for the conversion of methane - Google Patents

Method and catalyst for the conversion of methane Download PDF

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Publication number
WO1986007351A1
WO1986007351A1 PCT/US1986/001254 US8601254W WO8607351A1 WO 1986007351 A1 WO1986007351 A1 WO 1986007351A1 US 8601254 W US8601254 W US 8601254W WO 8607351 A1 WO8607351 A1 WO 8607351A1
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WO
WIPO (PCT)
Prior art keywords
oxide
process according
catalyst
group
methane
Prior art date
Application number
PCT/US1986/001254
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French (fr)
Inventor
Robert Fisher Hicks
Original Assignee
W. R. Grace & Co.
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Application filed by W. R. Grace & Co. filed Critical W. R. Grace & Co.
Publication of WO1986007351A1 publication Critical patent/WO1986007351A1/en

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    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C2/00Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms
    • C07C2/76Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by condensation of hydrocarbons with partial elimination of hydrogen
    • C07C2/82Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by condensation of hydrocarbons with partial elimination of hydrogen oxidative coupling
    • C07C2/84Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by condensation of hydrocarbons with partial elimination of hydrogen oxidative coupling catalytic
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C2521/00Catalysts comprising the elements, oxides or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium or hafnium
    • C07C2521/10Magnesium; Oxides or hydroxides thereof
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C2523/00Catalysts comprising metals or metal oxides or hydroxides, not provided for in group C07C2521/00
    • C07C2523/02Catalysts comprising metals or metal oxides or hydroxides, not provided for in group C07C2521/00 of the alkali- or alkaline earth metals or beryllium
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C2523/00Catalysts comprising metals or metal oxides or hydroxides, not provided for in group C07C2521/00
    • C07C2523/10Catalysts comprising metals or metal oxides or hydroxides, not provided for in group C07C2521/00 of rare earths
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00Technologies relating to chemical industry
    • Y02P20/50Improvements relating to the production of bulk chemicals
    • Y02P20/52Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

Definitions

  • This invention relates to a process and catalyst for converting methane in the presence of oxygen into hydrogen and higher hydrocarbons which include ethane and ethylene.
  • Methane is a plentiful hydrocarbon feedstock which is obtained principally from natural gas.
  • the methane content of natural gas can vary from 60% to 99%, the other components being ethane, propane, butane, carbon dioxide, and nitrogen.
  • World reserves are estimated to be about 2.5 x 10 12 ft 3 .
  • the production of chemicals from methane is hampered by the lack of catalytic processes capable of activating methane towards chemical transformations.
  • methane can be either combusted for its heating value, or steam reformed over iron or nickel catalysts to produce CO and H 2 .
  • the CO and H 2 are further reacted with N 2 to produce methanol and ammonia.
  • methane is an underutilized natural resource.
  • 4,239,658 disclose a novel catalyst and process for converting methane into a hydrocarbon product rich in ethylene and benzene.
  • the essential components of the catalyst are
  • a group Ila metal selected from the group consisting of magnesium and strontium composited with a passivated, spinel-coated refractory support or calcium composited with a passivated, non-zinc containing spinel-coated refractory support.
  • the process consists of contacting the catalyst with methane at elevated temperatures for a short period of time, and recovering the hydrocarbons which are produced. During the exposure to methane some of the metal oxides contained in the catalyst are reduced, and the surface of the catalyst becomes covered with coke, rendering it inactive. Before the methane can be readmitted to the reactor, the catalyst must be regenerated by contact with an oxygen or water containing gas at elevated temperature.
  • U. S. Patent No. 4,450,310 discloses a process for the conversion of methane into olefins and hydrogen by passing methane in the absence of oxygen and in the absence of water over a catalyst at temperatures above 500°C.
  • the catalyst is composed of mixed oxides from group 1A of the periodic table, including Li, Na, K, Rb, and Cs, and group IIA of the periodic table, including Be, Mg, Ca, Sr, and Ba, and optionally a promoter metal selected from Cu, Re, W, Zr, and Rh.
  • the reducible oxides can also be promoted with alkali metals (U. S. Patent 4,499,322) or alkaline earth metals (U. S. Patent 4,495,374) and stability is enhanced by the presence of phosphorus (PCT Published Application WO 85/00804).
  • alkali metals U. S. Patent 4,499,322
  • alkaline earth metals U. S. Patent 4,495,374
  • phosphorus PCT Published Application WO 85/00804
  • Other related work includes Ru promoted by alkali and alkaline earth metals (U. S. Patent 4,489,215), and the use of reducible rare earth oxides, CeO 2 (U. S. Patent 4,499,324) and Pr 6 O 11 (U. S. Patent 4,499,323).
  • Hinsen and Baerns disclose a new process for the synthesis of ethylene and ethane from methane.
  • the improvement of this process over previous processes is that methane and oxygen are fed simultaneously to the catalytic reactor, thereby obviating the need to cycle between reaction and catalyst regeneration.
  • the preferred method of adding the oxygen is either laterally along the length of the reactor, or to a large recirculating stream of the hydrocarbon gas. These methods of oxygen addition insure that the oxygen partial pressure is kept low, so as to maximize selectivity.
  • U. S. Patent No. 2,020,671 discloses the production of oxygenated organic compounds by reaction of methane with steam at temperatures of 200°-700°C in the presence of catalysts selected from metal salts of the alkaline earth metals, aluminum, magnesium, and zinc.
  • U. S. Patent No. 2,859,258 discloses the production of ethylene from methane in the presence of oxygen containing metal compound wherein the metal is selected from the second, third, and fourth groups of the periodic table, such as aluminum oxide, magnesium aluminum silicate, and magnesium aluminum molybdate.
  • methane can be converted into hydrogen, ethylene, ethane, and higher hydrocarbon products by contacting a gas containing methane and oxygen with a metal oxide of Group IIA metals of the Periodic Table such as Be, Mg, Ca, Sr, and Ba; a metal oxide of Group 111A metals of the Periodic Table, such as Sc, Y, and La; a metal oxide of the lanthanide series excluding Ce, such as Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; and mixtures thereof.
  • the catalytic reaction is preferably carried out at temperatures between 500 and 1000oC and pressures between 1 and 25 atmospheres. Some water, CO, and CO 2 is also produced as a byproduct of the reaction.
  • the present process is distinguished from previous known processes for the synthesis of hydrocarbons from methane in the presence of oxygen by the use of metal oxides which are not reducible, such as MgO, SrO, Y 2 O 3 , and La 2 O 3 .
  • a second feature of these catalysts is that they are basic and ionic metal oxides.
  • metal oxides which exhibit basic character, and do not have a redox potential are generally selective catalysts for synthesizing higher hydrocarbons from a mixture of methane and oxygen.
  • metal oxides of Group IIA, IIIA, and the lanthanide series excluding Ce can be improved by the addition of one or more promoter oxides selected from the following metals:
  • metals of Group 11A which are Be, Mg, Ca, Sr, and Ba;
  • (d) metals of the lanthanide series which are Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu;
  • the promoter oxide can be added by a variety of techniques.
  • the loading of the promoter can vary from a catalytically effective amount up to 50 wt%, and preferably less than 10 wt%.
  • the present process is also distinguished from previous known processes for the synthesis of hydrocarbons from methane in that an inert support material for the active metal oxide is not necessary, and in some cases may be deleterious to the overall performance of the catalyst.
  • the present process is further distinguished from previous known processes for the synthesis of hydrocarbons from methane by feeding methane and oxygen simultaneously to the catalytic reactor.
  • the catalysts described herein By using the catalysts described herein, the synthesis of hydrocarbons from methane can be carried out in the presence of oxygen without reducing the yield of hydrocarbon product.
  • Such a simultaneous and continuous feeding of a methane and oxygen mixture to the catalytic reactor eliminates the need for periodic catalyst regeneration, and it is the preferred mode of operation of the present invention.
  • Fig. 1 is a graph illustrating the dependence of product selectivity (based on moles of methane converted) upon methane conversion.
  • Fig. 2 is a graph illustrating the dependence of product selectivity upon operating temperature.
  • the catalyst can be composed of one or more base metal oxides of Group 11A, Group 111A, and the lanthanide series. These materials can be supplied as metal oxides, or as metal salts which are subsequently decomposed to the oxide form. Some examples of suitable metal salts are acetate, acetylacetonate. carbide, carbonate, hydroxide, formate, oxalate, nitrate, phosphate, sulfate, sulfide, tartrate, and halides such as fluoride, chloride, bromide, and iodide.
  • catalysts for the process described herein are the rare earth oxides which include La 2 O 3 , Y 2 O 3 , Pr 6 O 11 , Nd 2 O 3 , Sm 2 O 3 , Eu 2 O 3 , Gd 2 O 3 , TbO 2 , Dy 2 O 3 , Ho 2 O 3 , Er 2 O 3 , Tm 2 O 3 , Yb 2 O 3 , and
  • Lu 2 O 3 Lu 2 O 3 . These oxides may be used in their pure form, or as a mixture such as is commonly obtained from mineral deposits. If a mixture obtained from an ore is used, for example, bastnasite or monazite is used, then it is necessary to reduce the cerium content of the ore to a low level. Cerium oxide is an acidic solid, and can readily cycle between the +3 and +4 oxidation state.
  • CeO 2 converts methane in the presence of oxygen into CO and CO 2 , instead of ethylene, ethane, and higher hydrocarbons.
  • the catalyst can be composed of mixtures of the base metal oxides described above with promoter oxides, such as metal oxides of Groups 1A, IIA, 111A, 1VB, VB, 1B, and the lanthanide series.
  • promoter oxides such as metal oxides of Groups 1A, IIA, 111A, 1VB, VB, 1B, and the lanthanide series.
  • a preferred form of the catalyst is to deposit promoter amounts of elements of Groups 1A, 11A, 1VB, VB, or 1B onto a rare earth oxide.
  • Another preferred form of the catalyst is to deposit elements of Groups 1A, 111A, IVB, VB, 1B, or the lanthanide series onto an alkaline earth oxide.
  • the elements of Groups 1A, 11A, 1VB, VB, or 1B can be deposited onto a rare earth oxide by a variety of techniques. The same techniques apply for depositing elements of Groups 1A, 111A, IVB, VB, 1B, or the lanthanide series onto an alkaline earth oxide. Suitable techniques are adsorption, incipient-wetness impregnation, precipitation, coprecipitation, and dry-mixing. After depositing the element from one of the groups listed above, it is converted into the oxide form by treating in an atmosphere of oxygen at elevated temperatures. The weight loading of the promoter metal oxide deposit can vary between 0% and 50%, but preferably less than 10%.
  • the metal oxides described above can also be deposited on conventional supports, such as SiO 2 and Al 2 O 3 . These supports are not an essential part of the catalyst formulation, but may be used to give the catalyst pellet improved shape and/or improved mechanical strength and durability. If conventional supports are used, it is important that their acidity be reduced, otherwise the supports may catalyze the formation of carbon oxides from methane and oxygen.
  • the support acidity can be reduced by a number of means, such as using a high weight loading of the active metal oxide, doping the support with alkali metal prior to depositing the metal oxide, or using supports of low porosity.
  • a suitable method of preparing an unsupported catalyst is to deposit a promoter metal salt, such as from Groups 1A or 11A, onto a rare earth oxide by incipient-wetness impregnation.
  • the metal salt may be dissolved in water or another solvent and then mixed with the rare earth oxide, thereby wetting the surface of the oxide.
  • Aqueous solutions of the metal salt are desirable, and in this case, a water soluble salt is used.
  • acids and/or bases can be added to the solution.
  • the oxide is dried in an oven.
  • the solid for use in the process it may be calcined at high temperature for a period of time to convert the metal or metal salts to the metal oxide form.
  • the catalyst may be placed in a kiln, or a tube through which air may be passed, and heated for several hours at an elevated temperature, which preferably is between about 500 and 1000°C.
  • the unsupported metal oxide used as the catalyst can be prepared in a variety of pellet shapes and sizes, the shape and size being dictated by the need to have good contact between the gas and the solid surface of the catalyst.
  • the pellets can be prepared in the conventional manner using techniques well known to persons skilled in the art.
  • the catalyst pellet may be prepared by extrusion of a slurry of the metal oxide. Pellets formed in this manner are then dried and calcined at elevated temperatures.
  • the addition of promoter metal oxides, such as from Groups 1A or 11A of the Periodic Table, to the base metal oxide can be performed before or after the base metal oxide has been shaped into pellets.
  • the catalyst described above is charged to a reactor and contacted with a gas containing methane and oxygen at elevated temperatures.
  • feedstock for this process is natural gas which contains methane, ethane, propane, and other light hydrocarbons.
  • the methane content of the gas is between 60 to 100 volume percent, preferably 90 to 100 volume percent.
  • the natural gas is mixed with a stream containing oxygen to give a hydrocarbon to oxygen ratio (by volume) of 1 to 50, preferably between 2 and 15.
  • the stream containing oxygen may contain an inert diluent, such as nitrogen or argon.
  • substantially pure oxygen be used, because the diluents require a larger reactor size and must be removed from the process stream to purify the product.
  • the optimum ratio of hydrocarbon to oxygen fed to the reactor is chosen such that the yield of ethylene, ethane, and higher hydrocarbons is a maximum. This choice is governed by a number of factors, such as the catalyst composition, the reaction temperature and pressure, and the desired distribution of hydrocarbon products. As the oxygen partial pressure is increased relative to the methane partial pressure, the conversion of methane in the reactor increases. However, the yield of ethylene and ethane does not increase proportionally, because at high oxygen partial pressures more carbon oxides are produced relative to the desired hydrocarbon products. This tradeoff is illustrated in Figure 1 for the catalyst described in Example 18, using an integral fixed-bed reactor.
  • the selectivity (based on moles of methane converted) is cross-plotted against methane conversion and the methane to oxygen feed ratio.
  • the combined selectivity to ethylene, ethane, and higher hydrocarbons is identified as All C n in the figure.
  • These data were obtained at 700°C, 1 atm. pressure, a GHSV of 8x10 5 hr -1 (NTP), and an O 2 feed of 10 vol%.
  • Argon diluent was used in this experiment to maintain a constant space velocity.
  • Operating temperatures for contacting the methane and oxygen with the catalyst are between 500 and 1000oC, preferably between 550 and 850°C.
  • the optimum choice of reaction temperature depends on a number of factors, such as the composition of the catalyst, the partial pressures of hydrocarbon and oxidant, and the desired distribution of hydrocarbon products.
  • the dependence of hydrocarbon selectivity upon operating temperature is shown in Figure 2 for the catalyst described in Example 6. These data were obtained at a GHSV of 37,500 hr -1 (NTP), a methane partial pressure of 0.30 atm, an oxygen partial pressure of 0.05 atm, and an argon partial pressure of 0.65 atm. For all temperatures investigated in Figure 2 the oxygen conversion was 100%.
  • the data in Figure 2 indicate that maximum selectivities to higher hydrocarbons are observed at temperatures between 650 and 850oC.
  • the maximum selectivity to ethylene is observed at the highest temperature investigated, 850oC.
  • Operating pressures for contacting the methane and oxygen mixture with the catalyst are not critical. However, the total system pressure does effect the performance, since increasing the pressure tends to decrease the selectivity to higher hydrocarbons.
  • the effect of system pressure varies depending on the composition of the catalyst used. Preferred operating pressures are between 1 and 50 atms., more preferably between 1 and 20 atms.
  • the reactor contains a fixed-bed of catalyst, and the hydrocarbon and oxygen streams are mixed and fed to the reactor.
  • the reactor contains a fixed-bed of catalyst, the hydrocarbon feedstock is fed into one end of the reactor, and the oxygen is fed in at several inlets evenly spaced down the length of the reactor.
  • contacting schemes can be used whereby the catalyst is suspended in a fluidized-bed, an ebullating-bed, a moving-bed, or an entrained-bed, although a fixed-bed of catalyst is particularly well suited to contacting the solid oxide with the gas containing methane and oxygen.
  • Fixed-beds of catalyst can be operated in series or in parallel, depending on the desired yield and throughput of hydrocarbons required by the process.
  • the catalytic reaction In addition to producing ethylene, ethane, and higher hydrocarbons, the catalytic reaction also produces large amounts of hydrogen. This hydrogen is valuable as a fuel, as well as being a desirable reactant at a refinery where there are many hydrogen consuming reactions taking place.
  • This example describes the test procedure for the evaluation of the catalysts and sets forth the results.
  • the pellets of metal oxide from Examples 1-11 were separately charged to a quartz tube (4 mm inside diameter) to give a catalyst bed depth of 25.4 mm.
  • the quartz tube was then immersed in a fluidized sand-bath heater and brought up to reaction temperature over a 2 hr period under 50 cc/min of flowing argon.
  • the feed was switched to a mixture of methane (0.30 atm), oxygen (0.05 atm), and argon (0.65 atm), and the flow rate was set at a GHSV (gas hourly space velocity) of 37,500 hr -1 (NTP).
  • GHSV gas hourly space velocity
  • the SrO catalyst exhibits the highest selectivity, this advantage is offset by the low oxygen and methane conversion per pass.
  • the rare earth oxides including Y 2 O 3 , La 2 O 3 , Nd 2 O 3 , Sm 2 O 3 , Eu 2 O 3 , and Gd 2 O 3 , appear to offer the best overall performance characteristics, which are selectivities of approximately 60% to higher hydrocarbons, 100% O 2 conversion per pass, and a lower operating temperature (750-800°C) for achieving maximum hydrocarbon yield.
  • This example illustrates the preparation of a mixture of oxide catalysts according to the present invention.
  • a solution of lithium salt was prepared by dissolving LiNO 3 in distilled water. Lanthanum oxide was then impregnated to incipient-wetness by the solution of LiNO 3 . The mixture was dried in a vacuum oven at 110°C for 12 hours. The dried solid was then calcined in air at 600°C for 4 hours. Enough lithium was deposited on the La 2 O 3 to give a finished loading of 1.0 wt% Li 2 O.
  • catalysts were produced with 1.0 wt% of various metal oxides on either La 2 O 3 or MgO.
  • the catalysts prepared are listed in Tables 2 and 3.
  • This example describes the test procedure for the evaluation of the mixed oxide catalysts and sets forth the results.
  • the selectivity of the base metal oxide in this case La 2 O 3 or MgO
  • the selectivity of the base metal oxide can be increased by impregnating them with other metal oxides of Groups 1A, IIA, 111A, IVB, VB, and IB of the Periodic Table.
  • the especially preferred catalysts appear to be La 2 O 3 promoted with alkali metal oxides, La 2 O 3 promoted with alkaline earth oxides, and MgO promoted with Li 2 O.
  • This example illustrates the use of different amounts of a promoter oxide on a base metal oxide.
  • catalysts were produced with weight loadings of 0.25 to 10.0 wt% SrO on La 2 O 3 .
  • the catalysts prepared are listed in Table 4.
  • This example describes the test procedure for the evaluation of the strontium oxide-promoted lanthanum oxide catalysts prepared in Examples 30-33, and sets forth the results.
  • This example illustrates the use of rare earth oxide mixtures as catalysts for the oxidative coupling of methane, wherein the mixture is obtained from the mineral ore, and a portion of the cerium has been removed.
  • Bastnasite ore was obtained and dissolved in an acidic solution. From this solution varying levels of cerium was removed by extraction. The lanthanide concentrate was then converted into a rare earth carbonate, filtered, and dried. The carbonate was subsequently decomposed to the oxide by calcining in air at 750°C for 4 hours. Pure cerium oxide was also obtained for comparison with the rare earth oxide mixtures.
  • the catalysts prepared are listed in Table 5. The amount of La 2 O 3 , CeO 2 , and other rare earth oxides (Re 2 O 3 ) contained in each catalyst is given in the Table.
  • Example 39 This example describes the test procedure for the evaluation of the rare earth oxide mixtures prepared in Examples 35-38, and sets forth the results.
  • Each of the catalysts of Examples 35-38 were separately pressed into pellets of mesh size between 20 and 32, charged to the quartz reactor, and exposed to the reaction conditions as described in Example 12 above.
  • the experimental results for these catalyst samples are given in Table 5.
  • This example compares two catalysts according to the present invention with a prior art catalyst consisting of lead oxide supported on silica.
  • a lead oxide on silica catalyst was prepared according to the procedure given by W. Hinsen, W. Bytyn, and M. Baerns, Proc. 8th Intl. Cong. Catal. 3 , 581 (1984).
  • Cab-O-Sil HS5 silica was impregnated to incipient-wetness by a solution of lead acetate dissolved in distilled water. The mixture was dried in a vacuum oven at 120oC for 12 hours. The dried solid was then calcined in air at 800°C for 4 hours. Enough lead was deposited on the SiO 2 to give a finished loading of 11.2 wt% PbO.
  • the supported lead oxide catalyst was pressed into pellets of mesh size between 20 and 32, charged to the quartz reactor, and exposed to the reactor conditions as described in Example 12.
  • the experimental results for this catalyst and for the catalysts of Examples 6 and 18 are given in Table 6.
  • the 11.2% PbO/SiO 2 prior art catalyst exhibits selectivities to higher hydrocarbons similar to that of the catalysts disclosed in this invention, the activity of the prior art catalyst is low.
  • a reaction temperature of 900°C only 50% of the oxygen is converted per pass.
  • 100% of the oxygen is converted per pass at temperatures as low as 600°C.
  • a comparison of the data shown in Table 6 indicates that the relative amount of hydrogen produced by PbO/SiO 2 is much less than that produced by either La 2 O 3 or SrO/La 2 O 3 .
  • the catalysts disclosed in the present invention are superior to the prior art catalyst for the synthesis of hydrocarbons from methane in the presence of oxygen.

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Abstract

A process and catalyst for the synthesis of hydrogen, ethylene, ethane, and higher hydrocarbons from methane in the presence of oxygen. The catalyst comprises metal oxides selected from a Group IIA metal, a Group IIIA metal, a lanthanide series metal excluding Ce, or mixtures thereof and optionally a promoter metal oxide selected from a Group IA metal, a Group IIA metal, a Group IIIA metal, a lanthanide series metal, a Group IVB metal, a Group VB metal, a Group IB metal, or mixtures thereof.

Description

METHOD AND CATALYST FOR THE CONVERSION OF METHANE
Background of the Invention
1. Field of the Invention
This invention relates to a process and catalyst for converting methane in the presence of oxygen into hydrogen and higher hydrocarbons which include ethane and ethylene.
2. Description of the Previously Published Art Methane is a plentiful hydrocarbon feedstock which is obtained principally from natural gas. The methane content of natural gas can vary from 60% to 99%, the other components being ethane, propane, butane, carbon dioxide, and nitrogen. World reserves are estimated to be about 2.5 x 10 12 ft3. The production of chemicals from methane, however, is hampered by the lack of catalytic processes capable of activating methane towards chemical transformations.
Today methane can be either combusted for its heating value, or steam reformed over iron or nickel catalysts to produce CO and H2. The CO and H2 are further reacted with N2 to produce methanol and ammonia. As yet no attractive processes exist to convert methane directly into higher valued hydrocarbons, such as ethylene or propylene, which can then be used to produce liquid fuels, plastics, fibers, solvents, and a myriad of other organic compounds used by the chemical process industry. As a consequence, methane is an underutilized natural resource.
U. S. Patent Nos. 4,172,810, 4,205,194, and
4,239,658 disclose a novel catalyst and process for converting methane into a hydrocarbon product rich in ethylene and benzene. The essential components of the catalyst are
(1) a group VIII noble metal having an atomic number of 45 or greater, nickel, or group lb noble metal having an atomic number of 47 or greater,
(2) a group Via metal oxide which is capable of being reduced to a lower oxide, and
(3) a group Ila metal selected from the group consisting of magnesium and strontium composited with a passivated, spinel-coated refractory support or calcium composited with a passivated, non-zinc containing spinel-coated refractory support.
The process consists of contacting the catalyst with methane at elevated temperatures for a short period of time, and recovering the hydrocarbons which are produced. During the exposure to methane some of the metal oxides contained in the catalyst are reduced, and the surface of the catalyst becomes covered with coke, rendering it inactive. Before the methane can be readmitted to the reactor, the catalyst must be regenerated by contact with an oxygen or water containing gas at elevated temperature.
U. S. Patent No. 4,450,310 discloses a process for the conversion of methane into olefins and hydrogen by passing methane in the absence of oxygen and in the absence of water over a catalyst at temperatures above 500°C. The catalyst is composed of mixed oxides from group 1A of the periodic table, including Li, Na, K, Rb, and Cs, and group IIA of the periodic table, including Be, Mg, Ca, Sr, and Ba, and optionally a promoter metal selected from Cu, Re, W, Zr, and Rh. The improvement of this process over the one described previously is the reduced amount of coke deposited on the catalyst during reaction, which presumably allows the reaction to proceed for a longer period of time before the catalyst must be regenerated.
G. E. Keller and M. M. Bhasin in J. Catal. 73, 9 (1982) disclose a process to produce ethylene and ethane from methane whereby pure methane is fed over a catalyst at atmospheric pressure and temperatures of 500 to 1000°C. As the methane is passed through the reactor it reacts with the metal oxide catalyst producing ethane and ethylene, while simultaneously reducing the metal oxide. After a short exposure to methane, the catalyst must be regenerated, and the feed is switched to pure oxygen which reoxidizes the metal oxide. All catalysts were prepared by supporting a metal oxide on Al2O3. Active catalysts are supported oxides of Sn, Pb, Sb, Bi, Tl, Cd, and Mn. The authors suggest that the ability of these oxides to cycle between two oxidation states is essential for having good activity and selectivity for the conversion of methane into C2 hydrocarbon products.
Jones, Leonard, and Sofranko issued a series of patents which disclose a process similar to that of Keller and Bhasin for producing ethane and ethylene from methane. The reaction is carried out at atmospheric pressure, temperatures of 500 to 1000°C, and the methane and oxygen are fed separately in a
cyclic fashion. The improvements of the Jones process over the Keller process appear to be: (1) the use of a fluidized-bed catalytic reactor, instead of a fixed-bed catalytic reactor, and (2) supporting the active metal oxides on SiO2, instead of Al2O3. Jones, Leonard, and Sofranko also suggest that "reducible" metal oxides must be used as catalysts for this process, and these are oxides of Sb, Mn, Ge, Pb, Sn, In, and Bi. These oxides are claimed in U. S. Patent Nos. 4,443,644; 4,443,649; 4,443,645; 4,443,647; 4,444,984; 4,443,648; and 4,443,646, respectively. The reducible oxides can also be promoted with alkali metals (U. S. Patent 4,499,322) or alkaline earth metals (U. S. Patent 4,495,374) and stability is enhanced by the presence of phosphorus (PCT Published Application WO 85/00804). Other related work includes Ru promoted by alkali and alkaline earth metals (U. S. Patent 4,489,215), and the use of reducible rare earth oxides, CeO2 (U. S. Patent 4,499,324) and Pr6O11 (U. S. Patent 4,499,323).
Hinsen and Baerns (German Patent 3,237,079, Chem.-Ztg. 107, 223 (1983) and Proc. 8th Intl. Cong. Catal. 3, 581 (1984)) disclose a new process for the synthesis of ethylene and ethane from methane. The improvement of this process over previous processes is that methane and oxygen are fed simultaneously to the catalytic reactor, thereby obviating the need to cycle between reaction and catalyst regeneration. The preferred method of adding the oxygen is either laterally along the length of the reactor, or to a large recirculating stream of the hydrocarbon gas. These methods of oxygen addition insure that the oxygen partial pressure is kept low, so as to maximize selectivity. Good selectivities are observed at reaction temperatures of 650 to 750ºC and at low O2 partial pressures (PO2 = 0.05 to 0.10 atm) relative to methane (PCH4 = 0.25 to 0.50 atm). For the continuous feeding case, Baerns found that reducible oxides of Pb, Sb, Sn, Bi, Cd, Tl, and In are active and selective catalysts. Reducing the acidity of the support is also essential for maintaining good selectivity, and this can be achieved by using SiO2 support instead of TiO2, SiO2/Al2O3, or Al2O3, by increasing the PbO weight loading above 10.0%, and by promoting the catalyst with alkali.
U. S. Patent No. 2,020,671 discloses the production of oxygenated organic compounds by reaction of methane with steam at temperatures of 200°-700°C in the presence of catalysts selected from metal salts of the alkaline earth metals, aluminum, magnesium, and zinc.
U. S. Patent No. 2,859,258 discloses the production of ethylene from methane in the presence of oxygen containing metal compound wherein the metal is selected from the second, third, and fourth groups of the periodic table, such as aluminum oxide, magnesium aluminum silicate, and magnesium aluminum molybdate.
3. Objects of the Invention
It is an object of this invention to obtain a catalytic process to convert methane in the presence of oxygen to hydrogen, ethylene, ethane, and higher hydrocarbons with high selectivities and high methane conversion per pass.
It is a further object of this invention to develop an active and selective catalyst for the synthesis of hydrogen, ethylene, ethane, and higher hydrocarbons from methane in the presence of oxygen.
It is a further object of this invention to operate the process with simultaneous addition of methane and oxygen to the catalytic reactor, so as to avoid intermittent regeneration of the catalyst, thereby obtaining a continuous synthesis of hydrogen, ethylene, ethane, and higher hydrocarbons from methane.
These and further objects will become apparent as the description of the invention proceeds.
Summary of the Invention
It has been found that methane can be converted into hydrogen, ethylene, ethane, and higher hydrocarbon products by contacting a gas containing methane and oxygen with a metal oxide of Group IIA metals of the Periodic Table such as Be, Mg, Ca, Sr, and Ba; a metal oxide of Group 111A metals of the Periodic Table, such as Sc, Y, and La; a metal oxide of the lanthanide series excluding Ce, such as Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; and mixtures thereof. The catalytic reaction is preferably carried out at temperatures between 500 and 1000ºC and pressures between 1 and 25 atmospheres. Some water, CO, and CO2 is also produced as a byproduct of the reaction.
The present process is distinguished from previous known processes for the synthesis of hydrocarbons from methane in the presence of oxygen by the use of metal oxides which are not reducible, such as MgO, SrO, Y2O3, and La2O3. A second feature of these catalysts is that they are basic and ionic metal oxides. Thus, metal oxides which exhibit basic character, and do not have a redox potential, are generally selective catalysts for synthesizing higher hydrocarbons from a mixture of methane and oxygen.
It has further been found that the metal oxides of Group IIA, IIIA, and the lanthanide series excluding Ce can be improved by the addition of one or more promoter oxides selected from the following metals:
(a) metals of Group 1A, which are Li, Na, and K;
(b) metals of Group 11A, which are Be, Mg, Ca, Sr, and Ba;
(c) metals of Group 111A, which are Sc, Y, and La;
(d) metals of the lanthanide series, which are Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu;
(e) metals of Group IVB, which are Sn and Pb;
(f) metals of Group VB, which are Sb and Bi; and
(g) metals of Group IB, which are Cu, Ag, and Au. The promoter oxide can be added by a variety of techniques. The loading of the promoter can vary from a catalytically effective amount up to 50 wt%, and preferably less than 10 wt%.
The present process is also distinguished from previous known processes for the synthesis of hydrocarbons from methane in that an inert support material for the active metal oxide is not necessary, and in some cases may be deleterious to the overall performance of the catalyst.
The present process is further distinguished from previous known processes for the synthesis of hydrocarbons from methane by feeding methane and oxygen simultaneously to the catalytic reactor. By using the catalysts described herein, the synthesis of hydrocarbons from methane can be carried out in the presence of oxygen without reducing the yield of hydrocarbon product. Such a simultaneous and continuous feeding of a methane and oxygen mixture to the catalytic reactor eliminates the need for periodic catalyst regeneration, and it is the preferred mode of operation of the present invention.
This invention is further described in the following description of its preferred embodiments.
Brief Description of the Drawings
Fig. 1 is a graph illustrating the dependence of product selectivity (based on moles of methane converted) upon methane conversion.
Fig. 2 is a graph illustrating the dependence of product selectivity upon operating temperature.
Description of the Preferred Embodiments
The catalyst can be composed of one or more base metal oxides of Group 11A, Group 111A, and the lanthanide series. These materials can be supplied as metal oxides, or as metal salts which are subsequently decomposed to the oxide form. Some examples of suitable metal salts are acetate, acetylacetonate. carbide, carbonate, hydroxide, formate, oxalate, nitrate, phosphate, sulfate, sulfide, tartrate, and halides such as fluoride, chloride, bromide, and iodide.
Particularly suitable catalysts for the process described herein are the rare earth oxides which include La2O3, Y2O3 , Pr6O11, Nd2O3, Sm2O3, Eu2O3, Gd2O3, TbO2, Dy2O3, Ho2O3, Er2O3, Tm2O3, Yb2O3, and
Lu2O3. These oxides may be used in their pure form, or as a mixture such as is commonly obtained from mineral deposits. If a mixture obtained from an ore is used, for example, bastnasite or monazite is used, then it is necessary to reduce the cerium content of the ore to a low level. Cerium oxide is an acidic solid, and can readily cycle between the +3 and +4 oxidation state.
Consequently, CeO2 converts methane in the presence of oxygen into CO and CO2, instead of ethylene, ethane, and higher hydrocarbons.
In another embodiment of the invention the catalyst can be composed of mixtures of the base metal oxides described above with promoter oxides, such as metal oxides of Groups 1A, IIA, 111A, 1VB, VB, 1B, and the lanthanide series. A preferred form of the catalyst is to deposit promoter amounts of elements of Groups 1A, 11A, 1VB, VB, or 1B onto a rare earth oxide. Another preferred form of the catalyst is to deposit elements of Groups 1A, 111A, IVB, VB, 1B, or the lanthanide series onto an alkaline earth oxide.
The elements of Groups 1A, 11A, 1VB, VB, or 1B can be deposited onto a rare earth oxide by a variety of techniques. The same techniques apply for depositing elements of Groups 1A, 111A, IVB, VB, 1B, or the lanthanide series onto an alkaline earth oxide. Suitable techniques are adsorption, incipient-wetness impregnation, precipitation, coprecipitation, and dry-mixing. After depositing the element from one of the groups listed above, it is converted into the oxide form by treating in an atmosphere of oxygen at elevated temperatures. The weight loading of the promoter metal oxide deposit can vary between 0% and 50%, but preferably less than 10%.
The metal oxides described above can also be deposited on conventional supports, such as SiO2 and Al2O3. These supports are not an essential part of the catalyst formulation, but may be used to give the catalyst pellet improved shape and/or improved mechanical strength and durability. If conventional supports are used, it is important that their acidity be reduced, otherwise the supports may catalyze the formation of carbon oxides from methane and oxygen. The support acidity can be reduced by a number of means, such as using a high weight loading of the active metal oxide, doping the support with alkali metal prior to depositing the metal oxide, or using supports of low porosity.
A suitable method of preparing an unsupported catalyst is to deposit a promoter metal salt, such as from Groups 1A or 11A, onto a rare earth oxide by incipient-wetness impregnation. The metal salt may be dissolved in water or another solvent and then mixed with the rare earth oxide, thereby wetting the surface of the oxide. Aqueous solutions of the metal salt are desirable, and in this case, a water soluble salt is used. To facilitate dissolution of the metal salt, acids and/or bases can be added to the solution. After wetting the rare earth oxide with the salt solution, the oxide is dried in an oven. Finally, to prepare the solid for use in the process, it may be calcined at high temperature for a period of time to convert the metal or metal salts to the metal oxide form. For example, the catalyst may be placed in a kiln, or a tube through which air may be passed, and heated for several hours at an elevated temperature, which preferably is between about 500 and 1000°C.
The unsupported metal oxide used as the catalyst can be prepared in a variety of pellet shapes and sizes, the shape and size being dictated by the need to have good contact between the gas and the solid surface of the catalyst. The pellets can be prepared in the conventional manner using techniques well known to persons skilled in the art. For example, the catalyst pellet may be prepared by extrusion of a slurry of the metal oxide. Pellets formed in this manner are then dried and calcined at elevated temperatures. The addition of promoter metal oxides, such as from Groups 1A or 11A of the Periodic Table, to the base metal oxide can be performed before or after the base metal oxide has been shaped into pellets.
The method of catalyst preparation is further illustrated in the examples given below.
The catalyst described above is charged to a reactor and contacted with a gas containing methane and oxygen at elevated temperatures. The hydrocarbon
feedstock for this process is natural gas which contains methane, ethane, propane, and other light hydrocarbons. The methane content of the gas is between 60 to 100 volume percent, preferably 90 to 100 volume percent. The natural gas is mixed with a stream containing oxygen to give a hydrocarbon to oxygen ratio (by volume) of 1 to 50, preferably between 2 and 15. The stream containing oxygen may contain an inert diluent, such as nitrogen or argon. However, it is preferable that substantially pure oxygen be used, because the diluents require a larger reactor size and must be removed from the process stream to purify the product.
The optimum ratio of hydrocarbon to oxygen fed to the reactor is chosen such that the yield of ethylene, ethane, and higher hydrocarbons is a maximum. This choice is governed by a number of factors, such as the catalyst composition, the reaction temperature and pressure, and the desired distribution of hydrocarbon products. As the oxygen partial pressure is increased relative to the methane partial pressure, the conversion of methane in the reactor increases. However, the yield of ethylene and ethane does not increase proportionally, because at high oxygen partial pressures more carbon oxides are produced relative to the desired hydrocarbon products. This tradeoff is illustrated in Figure 1 for the catalyst described in Example 18, using an integral fixed-bed reactor. In this figure, the selectivity (based on moles of methane converted) is cross-plotted against methane conversion and the methane to oxygen feed ratio. The combined selectivity to ethylene, ethane, and higher hydrocarbons is identified as All Cn in the figure. These data were obtained at 700°C, 1 atm. pressure, a GHSV of 8x105 hr-1 (NTP), and an O2 feed of 10 vol%. Argon diluent was used in this experiment to maintain a constant space velocity.
Operating temperatures for contacting the methane and oxygen with the catalyst are between 500 and 1000ºC, preferably between 550 and 850°C. The optimum choice of reaction temperature depends on a number of factors, such as the composition of the catalyst, the partial pressures of hydrocarbon and oxidant, and the desired distribution of hydrocarbon products. The dependence of hydrocarbon selectivity upon operating temperature is shown in Figure 2 for the catalyst described in Example 6. These data were obtained at a GHSV of 37,500 hr-1 (NTP), a methane partial pressure of 0.30 atm, an oxygen partial pressure of 0.05 atm, and an argon partial pressure of 0.65 atm. For all temperatures investigated in Figure 2 the oxygen conversion was 100%. The data in Figure 2 indicate that maximum selectivities to higher hydrocarbons are observed at temperatures between 650 and 850ºC. The maximum selectivity to ethylene is observed at the highest temperature investigated, 850ºC.
Operating pressures for contacting the methane and oxygen mixture with the catalyst are not critical. However, the total system pressure does effect the performance, since increasing the pressure tends to decrease the selectivity to higher hydrocarbons. The effect of system pressure varies depending on the composition of the catalyst used. Preferred operating pressures are between 1 and 50 atms., more preferably between 1 and 20 atms.
Several different contacting schemes can be used to maximize the conversion of methane to ethylene, ethane, and higher hydrocarbons in the catalytic reactor. In one preferred embodiment, the reactor contains a fixed-bed of catalyst, and the hydrocarbon and oxygen streams are mixed and fed to the reactor. In a second preferred embodiment, the reactor contains a fixed-bed of catalyst, the hydrocarbon feedstock is fed into one end of the reactor, and the oxygen is fed in at several inlets evenly spaced down the length of the reactor. Other contacting schemes can be used whereby the catalyst is suspended in a fluidized-bed, an ebullating-bed, a moving-bed, or an entrained-bed, although a fixed-bed of catalyst is particularly well suited to contacting the solid oxide with the gas containing methane and oxygen. Fixed-beds of catalyst can be operated in series or in parallel, depending on the desired yield and throughput of hydrocarbons required by the process.
In addition to producing ethylene, ethane, and higher hydrocarbons, the catalytic reaction also produces large amounts of hydrogen. This hydrogen is valuable as a fuel, as well as being a desirable reactant at a refinery where there are many hydrogen consuming reactions taking place.
Having described the basic aspects of the invention, the following examples are given to illustrate specific embodiments thereof. Conversions and selectivities reported in the examples are given on a per mole of methane basis.
EXAMPLES 1 - 11
These examples illustrate the preparation of pure oxide catalysts according to the present invention.
Pure metal oxides of Groups IIA and 111A of the Periodic Table, and metal oxides of the lanthanide series were obtained and calcined at 900°C in a kiln for 4 hours. These solids were then pressed into pellets, crushed, and sieved to a mesh size between 20 and 32. The oxides are listed in Table 1.
Example 12
This example describes the test procedure for the evaluation of the catalysts and sets forth the results.
The pellets of metal oxide from Examples 1-11 were separately charged to a quartz tube (4 mm inside diameter) to give a catalyst bed depth of 25.4 mm. The quartz tube was then immersed in a fluidized sand-bath heater and brought up to reaction temperature over a 2 hr period under 50 cc/min of flowing argon. Once at reaction temperature, the feed was switched to a mixture of methane (0.30 atm), oxygen (0.05 atm), and argon (0.65 atm), and the flow rate was set at a GHSV (gas hourly space velocity) of 37,500 hr-1 (NTP). Periodically, the effluent from the reactor was analyzed by on-line gas chromatography. The reactions were carried out from 4 to 12 hours, during which time little or no deactivation of the catalysts occurred. Results for several of the metal oxides tested are shown in Table 1. In these tests the reaction temperature was chosen to give the maximum yield of hydrocarbon products. The bed inlet temperature corresponding to this optimum is shown in Table 1. The combined selectivity to ethylene, ethane, and higher hydrocarbons is listed under All Cn in the Table, and the last column gives the mole ratio of hydrogen to ethylene and ethane in the reactor effluent. Oxygen and carbon material balances were closed to within + 5%.
Figure imgf000019_0001
From the data shown in Table 1, it is evident that all of the pure metal oxide catalysts exhibit high selectivities to ethylene, ethane, and higher hydrocarbons. It is also evident that a large amount of hydrogen is produced along with the hydrocarbons, such that the mole ratio of H2 to C2H4 and C2H6 in the product varies between 0.4 and 1.7. This hydrogen can be used as a fuel, or in a refinery complex where there are many hydrogen consuming reactions taking place. Particularly high selectivities to hydrocarbon products are exhibited by MgO, SrO, Y2O3, La2O3, Nd2O3, Sm2O3, Eu2O3, and Gd2O3. Although the SrO catalyst exhibits the highest selectivity, this advantage is offset by the low oxygen and methane conversion per pass. Of the oxides listed, the rare earth oxides, including Y2O3, La2O3, Nd2O3, Sm2O3, Eu2O3, and Gd2O3, appear to offer the best overall performance characteristics, which are selectivities of approximately 60% to higher hydrocarbons, 100% O2 conversion per pass, and a lower operating temperature (750-800°C) for achieving maximum hydrocarbon yield.
EXAMPLE 13
This example illustrates the preparation of a mixture of oxide catalysts according to the present invention.
A solution of lithium salt was prepared by dissolving LiNO3 in distilled water. Lanthanum oxide was then impregnated to incipient-wetness by the solution of LiNO3. The mixture was dried in a vacuum oven at 110°C for 12 hours. The dried solid was then calcined in air at 600°C for 4 hours. Enough lithium was deposited on the La2O3 to give a finished loading of 1.0 wt% Li2O.
EXAMPLES 14-28
These examples illustrate the preparation of additional mixtures of oxide catalysts according to the present invention.
Following the procedure of Example 13, catalysts were produced with 1.0 wt% of various metal oxides on either La2O3 or MgO. The catalysts prepared are listed in Tables 2 and 3.
Example 29
This example describes the test procedure for the evaluation of the mixed oxide catalysts and sets forth the results.
Each of the catalysts of Examples 13-28 were separately pressed into pellets of mesh size between 20 and 32, charged to the quartz reactor, and exposed to the reaction conditions as described in Example 12 above. The experimental results for these catalyst samples are given in Tables 2 and 3.
Figure imgf000022_0001
Figure imgf000023_0001
Comparison of the data in Tables 2 and 3 indicates that the selectivity of the base metal oxide, in this case La2O3 or MgO, can be increased by impregnating them with other metal oxides of Groups 1A, IIA, 111A, IVB, VB, and IB of the Periodic Table. The especially preferred catalysts appear to be La2O3 promoted with alkali metal oxides, La2O3 promoted with alkaline earth oxides, and MgO promoted with Li2O.
Examples 30-33
This example illustrates the use of different amounts of a promoter oxide on a base metal oxide.
Following the procedure of Example 13 and using Sr(NO3)2 instead of LiNO3, catalysts were produced with weight loadings of 0.25 to 10.0 wt% SrO on La2O3. The catalysts prepared are listed in Table 4.
Example 34
This example describes the test procedure for the evaluation of the strontium oxide-promoted lanthanum oxide catalysts prepared in Examples 30-33, and sets forth the results.
Each of the catalysts of Examples 30-34 were separately pressed into pellets of mesh size between 20 and 32, charged to the quartz reactor, and exposed to the reaction conditions as described in Example 12 above. The experimental results for these catalyst samples are given in Table 4.
Figure imgf000025_0001
Comparison of the data in Table 4 indicates that the weight loading of the promoter oxide is not critical. An increase in selectivity to higher hydrocarbons of 10 percentage points is achieved by depositing SrO onto La2O3, irrespective of whether the weight loading of strontium oxide is 0.25% or 10.0%.
Example 35-38
This example illustrates the use of rare earth oxide mixtures as catalysts for the oxidative coupling of methane, wherein the mixture is obtained from the mineral ore, and a portion of the cerium has been removed.
Bastnasite ore was obtained and dissolved in an acidic solution. From this solution varying levels of cerium was removed by extraction. The lanthanide concentrate was then converted into a rare earth carbonate, filtered, and dried. The carbonate was subsequently decomposed to the oxide by calcining in air at 750°C for 4 hours. Pure cerium oxide was also obtained for comparison with the rare earth oxide mixtures. The catalysts prepared are listed in Table 5. The amount of La2O3, CeO2, and other rare earth oxides (Re2O3) contained in each catalyst is given in the Table.
Example 39 This example describes the test procedure for the evaluation of the rare earth oxide mixtures prepared in Examples 35-38, and sets forth the results. Each of the catalysts of Examples 35-38 were separately pressed into pellets of mesh size between 20 and 32, charged to the quartz reactor, and exposed to the reaction conditions as described in Example 12 above. The experimental results for these catalyst samples are given in Table 5.
Figure imgf000028_0001
A comparison of the data in Table 5 indicates that a decrease in the selectivity to higher hydrocarbons occurs as the CeO2 content of the rare earth oxide increases. Mixtures containing up to 10 wt% CeO2 give acceptable results. However, at higher concentrations of cerium the selectivity decreases to a low value, and pure CeO2 converts essentially all of the methane to carbon oxides.
Example 40
This example compares two catalysts according to the present invention with a prior art catalyst consisting of lead oxide supported on silica.
A lead oxide on silica catalyst was prepared according to the procedure given by W. Hinsen, W. Bytyn, and M. Baerns, Proc. 8th Intl. Cong. Catal. 3 , 581 (1984). Cab-O-Sil HS5 silica was impregnated to incipient-wetness by a solution of lead acetate dissolved in distilled water. The mixture was dried in a vacuum oven at 120ºC for 12 hours. The dried solid was then calcined in air at 800°C for 4 hours. Enough lead was deposited on the SiO2 to give a finished loading of 11.2 wt% PbO.
The supported lead oxide catalyst was pressed into pellets of mesh size between 20 and 32, charged to the quartz reactor, and exposed to the reactor conditions as described in Example 12. The experimental results for this catalyst and for the catalysts of Examples 6 and 18 are given in Table 6.
Figure imgf000030_0001
Although the 11.2% PbO/SiO2 prior art catalyst exhibits selectivities to higher hydrocarbons similar to that of the catalysts disclosed in this invention, the activity of the prior art catalyst is low. For a reaction temperature of 900°C, only 50% of the oxygen is converted per pass. For the La2O3 and SrO/La2O3 catalysts, on the other hand, 100% of the oxygen is converted per pass at temperatures as low as 600°C. Also, a comparison of the data shown in Table 6 indicates that the relative amount of hydrogen produced by PbO/SiO2 is much less than that produced by either La2O3 or SrO/La2O3. Thus, the catalysts disclosed in the present invention are superior to the prior art catalyst for the synthesis of hydrocarbons from methane in the presence of oxygen.
It is understood that the foregoing detailed description is given merely by way of illustration and that many variations may be made therein without departing from the spirit of this invention.

Claims

WHAT IS CLAIMED IS:
1. In a process for converting methane into hydrogen, ethylene, ethane, and higher hydrocarbon products by contacting a gas containing a mixture of methane and oxygen with a catalyst, the improvement comprising using as the catalyst one or more metal oxides where the metal is selected from the group consisting of metals of
(a) Group IIA metals of the Periodic Table, which are Be, Mg, Ca, Sr, or Ba;
(b) Group 111A metals of the Periodic Table, which are Sc, Y, or La;
(c) the lanthanide series metals excluding Ce, which are Pr, Nd, Sm, Eu, Gd, Tb, Dy,
Ho, Er, Tm, Yb, or Lu; and
(d) mixtures thereof.
2. A process according to Claim 1, wherein the catalyst is a metal oxide of a Group IIA metal selected from the group consisting of Be, Mg, Ca, Sr, and Ba.
3. A process according to Claim 2, wherein the catalyst is MgO.
4. A process according to Claim 2, wherein the catalyst is SrO.
5. A process according to Claim 1, wherein the catalyst is a metal oxide of a Group 111A metal selected from the group consisting of Sc, Y, and La.
6. A process according to Claim 5, wherein the metal oxide is Y2O3.
7. A process according to Claim 5, wherein the metal oxide is La2O3.
8. A process according to Claim 1, wherein the catalyst is a metal oxide of a lanthanide series metal selected from the group consisting of Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and mixtures thereof.
9. A process according to Claim 1, wherein the metal oxide is a mixture of rare earth oxides as is formed in rare earth minerals, but with a portion of the CeO2 removed.
10. A process according to Claim 1, wherein the gas containing methane and oxygen is contacted with the catalyst at temperatures between 500 and 1000°C.
11. A process according to Claim 1, wherein the pressure of the gas in the contacting zone is between 1 and 50 atmospheres.
12. A process according to Claim 1, wherein the mole ratio of methane to oxygen fed to the reactor is between 0.5 and 50.
13. A process according to Claim 1, wherein the gas containing methane and oxygen is contacted with the catalyst at temperatures between 550 and 850°C, the pressure of the gas in the contacting zone is between 1 and 20 atmospheres, and the mole ratio of methane to oxygen fed to the reactor is between 2 and 20.
14. A process according to Claim 1, wherein the oxygen feed consists of 20 to 100 volume percent oxygen.
15. A process according to Claim 14, wherein the oxygen feed is essentially pure oxygen.
16. A process according to Claim 1 , wherein the methane feed consists of 60 to 100 volume percent methane.
17. A process according to Claim 16, wherein the methane feed is essentially pure methane.
18. A process according to Claim 1, wherein the catalyst comprises the catalyst of Claim 1 as a first base metal oxide and wherein it further comprises a second promoter metal oxide where the metal is selected from the group consisting of
(a) metals of Group 1A, which are Li, Na, and K;
(b) metals of Group IIA, which are Be, Mg, Ca, Sr, and Ba;
(c) metals of Group 111A, which are Sc, Y, and La;
(d) metals of the lanthanide series, which are Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu;
(e) metals of Group IVB, which are Sn and Pb;
(f) metals of Group VB, which are Sb and Bi;
(g) metals of Group IB, which are Cu, Ag, and Au, and
(h) mixtures thereof.
19. A process according to Claim 18, wherein said second promoter oxide is present in an amount from a catalytically effective amount to 50% by weight of the mixture.
20. A process according to Claim 18, vherein the base metal oxide is MgO, CaO, or SrO and the promoter oxide is Li2O.
21. A process according to Claim 18, wherein the base metal oxide is Y2O3 and the promoter oxide is Li2O, BeO, MgO, CaO, SrO, BaO, tin oxide, lead oxide, antimony oxide, bismuth oxide, copper oxide, silver oxide, or gold oxide.
22. A process according to Claim 18, wherein the base metal oxide is La2O3 and the promoter oxide is Li2O, BeO, MgO, CaO, SrO, BaO, tin oxide, lead oxide, antimony oxide, bismuth oxide, copper oxide, silver oxide, or gold oxide.
23. A process according to Claim 18, wherein the base metal oxide is a mixture of rare earth oxides, as is formed in rare earth minerals, but with a portion of the CeO2 removed, and the promoter oxide is Li2O, BeO, MgO, CaO, SrO, BaO, tin oxide, lead oxide, antimony oxide, bismuth oxide, copper oxide, silver oxide, or gold oxide.
24. A process according to Claim 18, wherein the gas containing methane and oxygen is contacted with the catalyst at temperatures between 500 and 1000°C.
25. A process according to Claim 18, wherein the pressure of the gas in the contacting zone is between 1 and 50 atmospheres.
26. A process according to Claim 18, wherein the mole ratio of methane to oxygen fed to the reactor is between 0.5 and 50.
27. A process according to Claim 18, wherein the gas containing methane and oxygen is contacted with the catalyst at temperatures between 550 and 850°C, the pressure of the gas in the contacting zone is between 1 and 20 atmospheres, and the mole ratio of methane to oxygen fed to the reactor is between 2 and 20.
28. A process according to Claim 18, wherein the oxygen feed consists of 20 to 100 volume percent oxygen.
29. A process according to Claim 28, wherein the oxygen feed is essentially pure oxygen.
30. A process according to Claim 18, wherein the methane feed consists of 60 to 100 volume percent methane.
31. A process according to Claim 30, wherein the methane feed is essentially pure methane.
32. A catalyst for converting methane in the presence of oxygen into higher hydrocarbon products comprising
(1) a first base metal oxide where the metal is selected from the group consisting of metals of
(a) Group IIA metals of the Periodic Table, which are Be, Mg, Ca, Sr, and Ba;
(b) Group 111A metals, of the Periodic Table, which are Sc, Y, and La;
(c) the lanthanide series metals excluding Ce, which are Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; and
(d) mixtures thereof; and
(2) a second promoter oxide where the metal is selected from the group consisting of
(a) Group 1A metals of the Periodic Table, which are Li, Na, and K; (b) Group IIA metals of the Periodic Table, which are Be, Mg, Ca, Sr, and Ba;
(c) Group 111A metals of the Periodic Table, which are Sc, Y, and La;
(d) the lanthanide series metals, which are Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu;
(e) Group IVB metals of the Periodic Table, which are Sn and Pb;
(f) Group VB metals of the Periodic Table which are Sb and Bi;
(g) Group IB metals of the Periodic Table, which are Cu, Ag, and Au; and
(h) mixtures thereof.
33. A catalyst according to Claim 32, wherein the promoter oxide is present in an amount up to 50 wt% of the mixture.
34. A catalyst according to Claim 33, wherein the promoter oxide is present in an amount up to 10 wt% of the mixture.
35. A catalyst according to Claim 32, wherein the base metal oxide is MgO, CaO, or SrO and the promoter oxide is Li2O.
36. A catalyst according to Claim 32, wherein the base metal oxide is Y2O3 and the promoter oxide is Li2O, BeO, MgO, CaO, SrO, BaO, tin oxide, lead oxide, antimony oxide, bismuth oxide, copper oxide, silver oxide, or gold oxide.
37. A catalyst according to Claim 32, wherein the base metal oxide is La2O3 and the promoter oxide is Li2O, BeO, MgO, CaO, SrO, BaO, tin oxide, lead oxidee antimony oxide, bismuth oxide, copper oxide, silver oxide, or gold oxide.
38. A catalyst according to Claim 32, wherein the base metal oxide is a mixture of rare earth oxides, as is formed in rare earth minerals, but with a portion of the. CeO2 removed, and the promoter oxide is Li2O, BeO, MgO, CaO, SrO, BaO, tin oxide, lead oxide, antimony oxide, bismuth oxide, copper oxide, silver oxide, or gold oxide.
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Cited By (37)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4826796A (en) * 1988-03-28 1989-05-02 Institute Of Gas Technology Mixed basic metal oxide catalyst for oxidative coupling of methane
EP0320301A3 (en) * 1987-12-11 1989-08-23 Ube Industries, Ltd. Process for preparation of hydrocarbons
US4918257A (en) * 1988-07-15 1990-04-17 Quantum Chemical Corporation Catalytic conversion of methane to higher hydrocarbons
US4929787A (en) * 1987-08-05 1990-05-29 Institut Francais Du Petrole Process for converting methane to higher hydrocarbons
DE4103431A1 (en) * 1990-02-07 1991-08-08 Snam Progetti Converting methane into higher hydrocarbon(s) - using catalyst based on mixed oxide of Gp=IV, rare earth, alkaline, alkali earth and Gp=IIB metal(s)
US5061670A (en) * 1988-06-29 1991-10-29 501 Societe Nationale Elf Aquitaine Process for the preparation of a catalyst capable of promoting the oxidative conversion of methane into higher hydrocarbons and use of catalyst
US5105046A (en) * 1990-12-12 1992-04-14 Amoco Corporation Oxidative conversion of lower alkanes to higher hydrocarbons via fluorine-containing materials
US5118654A (en) * 1991-08-22 1992-06-02 Council Of Scientific & Industrial Research Process for the preparation of an improved Li-promoted MgO catalyst useful for oxidative coupling of methane to ethane and ethylene
US5260497A (en) * 1990-02-07 1993-11-09 Snamprogetti S.P.A. Catalytic system for converting methane into higher hydrocarbons
US5478370A (en) * 1994-07-01 1995-12-26 Amoco Corporation Method for producing synthesis gas
DE102010031099A1 (en) * 2010-07-08 2012-01-12 Technische Universität Berlin Lanthanide oxide obtained by heating a lanthanide hydroxide and by calcinating, useful as a catalyst in the conversion of methane to higher hydrocarbons, preferably in the oxidative coupling of methane to ethane or ethylene
US9133079B2 (en) 2012-01-13 2015-09-15 Siluria Technologies, Inc. Process for separating hydrocarbon compounds
US9334204B1 (en) 2015-03-17 2016-05-10 Siluria Technologies, Inc. Efficient oxidative coupling of methane processes and systems
US9352295B2 (en) 2014-01-09 2016-05-31 Siluria Technologies, Inc. Oxidative coupling of methane implementations for olefin production
US9446387B2 (en) 2011-05-24 2016-09-20 Siluria Technologies, Inc. Catalysts for petrochemical catalysis
US9446397B2 (en) 2012-02-03 2016-09-20 Siluria Technologies, Inc. Method for isolation of nanomaterials
US9469577B2 (en) 2012-05-24 2016-10-18 Siluria Technologies, Inc. Oxidative coupling of methane systems and methods
US9670113B2 (en) 2012-07-09 2017-06-06 Siluria Technologies, Inc. Natural gas processing and systems
US9718054B2 (en) 2010-05-24 2017-08-01 Siluria Technologies, Inc. Production of ethylene with nanowire catalysts
US9738571B2 (en) 2013-03-15 2017-08-22 Siluria Technologies, Inc. Catalysts for petrochemical catalysis
US9751818B2 (en) 2011-11-29 2017-09-05 Siluria Technologies, Inc. Nanowire catalysts and methods for their use and preparation
US9751079B2 (en) 2014-09-17 2017-09-05 Silura Technologies, Inc. Catalysts for natural gas processes
US9944573B2 (en) 2016-04-13 2018-04-17 Siluria Technologies, Inc. Oxidative coupling of methane for olefin production
US9956544B2 (en) 2014-05-02 2018-05-01 Siluria Technologies, Inc. Heterogeneous catalysts
US10047020B2 (en) 2013-11-27 2018-08-14 Siluria Technologies, Inc. Reactors and systems for oxidative coupling of methane
US10377682B2 (en) 2014-01-09 2019-08-13 Siluria Technologies, Inc. Reactors and systems for oxidative coupling of methane
US10787398B2 (en) 2012-12-07 2020-09-29 Lummus Technology Llc Integrated processes and systems for conversion of methane to multiple higher hydrocarbon products
US10793490B2 (en) 2015-03-17 2020-10-06 Lummus Technology Llc Oxidative coupling of methane methods and systems
US10836689B2 (en) 2017-07-07 2020-11-17 Lummus Technology Llc Systems and methods for the oxidative coupling of methane
US10865165B2 (en) 2015-06-16 2020-12-15 Lummus Technology Llc Ethylene-to-liquids systems and methods
US10894751B2 (en) 2014-01-08 2021-01-19 Lummus Technology Llc Ethylene-to-liquids systems and methods
US10960343B2 (en) 2016-12-19 2021-03-30 Lummus Technology Llc Methods and systems for performing chemical separations
US11001543B2 (en) 2015-10-16 2021-05-11 Lummus Technology Llc Separation methods and systems for oxidative coupling of methane
US11001542B2 (en) 2017-05-23 2021-05-11 Lummus Technology Llc Integration of oxidative coupling of methane processes
US11186529B2 (en) 2015-04-01 2021-11-30 Lummus Technology Llc Advanced oxidative coupling of methane
US11370724B2 (en) 2012-05-24 2022-06-28 Lummus Technology Llc Catalytic forms and formulations
US12227466B2 (en) 2021-08-31 2025-02-18 Lummus Technology Llc Methods and systems for performing oxidative coupling of methane

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114920279B (en) * 2022-05-09 2023-10-24 西南石油大学 Preparation method and application of oxygen carrier for low-temperature oxidation of methane to prepare hydrogen

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3957690A (en) * 1972-03-15 1976-05-18 Alexandr Vasilievich Bobolev Heterogeneous catalyst for oxidation of propylene into propylene oxide in the liquid phase and method for preparing it
US4060498A (en) * 1972-06-02 1977-11-29 Hitachi, Ltd. Process for steam reforming of hydrocarbons
JPS58193736A (en) * 1982-05-06 1983-11-11 Mitsubishi Heavy Ind Ltd Catalyst for production of gas enriched with hydrogen
US4450310A (en) * 1983-03-04 1984-05-22 The Standard Oil Company Conversion of methane to olefins and hydrogen
US4484017A (en) * 1983-08-01 1984-11-20 Phillips Petroleum Company Olefin aromatization process
US4499323A (en) * 1984-04-16 1985-02-12 Atlantic Richfield Company Methane conversion
US4523049A (en) * 1984-04-16 1985-06-11 Atlantic Richfield Company Methane conversion process

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61165340A (en) * 1985-01-14 1986-07-26 Idemitsu Kosan Co Ltd Production of hydrocarbon

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3957690A (en) * 1972-03-15 1976-05-18 Alexandr Vasilievich Bobolev Heterogeneous catalyst for oxidation of propylene into propylene oxide in the liquid phase and method for preparing it
US4060498A (en) * 1972-06-02 1977-11-29 Hitachi, Ltd. Process for steam reforming of hydrocarbons
JPS58193736A (en) * 1982-05-06 1983-11-11 Mitsubishi Heavy Ind Ltd Catalyst for production of gas enriched with hydrogen
US4450310A (en) * 1983-03-04 1984-05-22 The Standard Oil Company Conversion of methane to olefins and hydrogen
US4484017A (en) * 1983-08-01 1984-11-20 Phillips Petroleum Company Olefin aromatization process
US4499323A (en) * 1984-04-16 1985-02-12 Atlantic Richfield Company Methane conversion
US4523049A (en) * 1984-04-16 1985-06-11 Atlantic Richfield Company Methane conversion process

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
LUNGSFORD et al., "Evidence for the Formation of Gas Phase Radicals at Surface", pp. 920-926, Symposium on the New Surface Science in Catalysis Presented before the Division of Colloid and Curface Chemistry and the Division of Petroleum Chemistry, Philadelphia Meeting, August 26-31, 1984, see pages 922 and 923. *
OTSUKA et al., "The Catalyst Active and Selective in Oxidative Coupling of Methane", Chemistry Letters, pp. 499-500 (April 1985), see Entire Document. *
See also references of EP0227750A4 *

Cited By (68)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4929787A (en) * 1987-08-05 1990-05-29 Institut Francais Du Petrole Process for converting methane to higher hydrocarbons
EP0320301A3 (en) * 1987-12-11 1989-08-23 Ube Industries, Ltd. Process for preparation of hydrocarbons
US4996382A (en) * 1987-12-11 1991-02-26 Ube Industries, Ltd. Process for preparation of hydrocarbons
US4826796A (en) * 1988-03-28 1989-05-02 Institute Of Gas Technology Mixed basic metal oxide catalyst for oxidative coupling of methane
US5061670A (en) * 1988-06-29 1991-10-29 501 Societe Nationale Elf Aquitaine Process for the preparation of a catalyst capable of promoting the oxidative conversion of methane into higher hydrocarbons and use of catalyst
US4918257A (en) * 1988-07-15 1990-04-17 Quantum Chemical Corporation Catalytic conversion of methane to higher hydrocarbons
DE4103431A1 (en) * 1990-02-07 1991-08-08 Snam Progetti Converting methane into higher hydrocarbon(s) - using catalyst based on mixed oxide of Gp=IV, rare earth, alkaline, alkali earth and Gp=IIB metal(s)
US5260497A (en) * 1990-02-07 1993-11-09 Snamprogetti S.P.A. Catalytic system for converting methane into higher hydrocarbons
US5105046A (en) * 1990-12-12 1992-04-14 Amoco Corporation Oxidative conversion of lower alkanes to higher hydrocarbons via fluorine-containing materials
US5118654A (en) * 1991-08-22 1992-06-02 Council Of Scientific & Industrial Research Process for the preparation of an improved Li-promoted MgO catalyst useful for oxidative coupling of methane to ethane and ethylene
US5478370A (en) * 1994-07-01 1995-12-26 Amoco Corporation Method for producing synthesis gas
US10195603B2 (en) 2010-05-24 2019-02-05 Siluria Technologies, Inc. Production of ethylene with nanowire catalysts
US9718054B2 (en) 2010-05-24 2017-08-01 Siluria Technologies, Inc. Production of ethylene with nanowire catalysts
DE102010031099A1 (en) * 2010-07-08 2012-01-12 Technische Universität Berlin Lanthanide oxide obtained by heating a lanthanide hydroxide and by calcinating, useful as a catalyst in the conversion of methane to higher hydrocarbons, preferably in the oxidative coupling of methane to ethane or ethylene
US11795123B2 (en) 2011-05-24 2023-10-24 Lummus Technology Llc Catalysts for petrochemical catalysis
US9963402B2 (en) 2011-05-24 2018-05-08 Siluria Technologies, Inc. Catalysts for petrochemical catalysis
US9446387B2 (en) 2011-05-24 2016-09-20 Siluria Technologies, Inc. Catalysts for petrochemical catalysis
US10654769B2 (en) 2011-05-24 2020-05-19 Siluria Technologies, Inc. Catalysts for petrochemical catalysis
US11078132B2 (en) 2011-11-29 2021-08-03 Lummus Technology Llc Nanowire catalysts and methods for their use and preparation
US9751818B2 (en) 2011-11-29 2017-09-05 Siluria Technologies, Inc. Nanowire catalysts and methods for their use and preparation
US9133079B2 (en) 2012-01-13 2015-09-15 Siluria Technologies, Inc. Process for separating hydrocarbon compounds
US9527784B2 (en) 2012-01-13 2016-12-27 Siluria Technologies, Inc. Process for separating hydrocarbon compounds
US11254626B2 (en) 2012-01-13 2022-02-22 Lummus Technology Llc Process for separating hydrocarbon compounds
US9446397B2 (en) 2012-02-03 2016-09-20 Siluria Technologies, Inc. Method for isolation of nanomaterials
US9556086B2 (en) 2012-05-24 2017-01-31 Siluria Technologies, Inc. Oxidative coupling of methane systems and methods
US9469577B2 (en) 2012-05-24 2016-10-18 Siluria Technologies, Inc. Oxidative coupling of methane systems and methods
US11370724B2 (en) 2012-05-24 2022-06-28 Lummus Technology Llc Catalytic forms and formulations
US11242298B2 (en) 2012-07-09 2022-02-08 Lummus Technology Llc Natural gas processing and systems
US9670113B2 (en) 2012-07-09 2017-06-06 Siluria Technologies, Inc. Natural gas processing and systems
US9969660B2 (en) 2012-07-09 2018-05-15 Siluria Technologies, Inc. Natural gas processing and systems
US11168038B2 (en) 2012-12-07 2021-11-09 Lummus Technology Llc Integrated processes and systems for conversion of methane to multiple higher hydrocarbon products
US10787398B2 (en) 2012-12-07 2020-09-29 Lummus Technology Llc Integrated processes and systems for conversion of methane to multiple higher hydrocarbon products
US10308565B2 (en) 2013-03-15 2019-06-04 Silura Technologies, Inc. Catalysts for petrochemical catalysis
US10865166B2 (en) 2013-03-15 2020-12-15 Siluria Technologies, Inc. Catalysts for petrochemical catalysis
US9738571B2 (en) 2013-03-15 2017-08-22 Siluria Technologies, Inc. Catalysts for petrochemical catalysis
US11407695B2 (en) 2013-11-27 2022-08-09 Lummus Technology Llc Reactors and systems for oxidative coupling of methane
US10047020B2 (en) 2013-11-27 2018-08-14 Siluria Technologies, Inc. Reactors and systems for oxidative coupling of methane
US10927056B2 (en) 2013-11-27 2021-02-23 Lummus Technology Llc Reactors and systems for oxidative coupling of methane
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US9352295B2 (en) 2014-01-09 2016-05-31 Siluria Technologies, Inc. Oxidative coupling of methane implementations for olefin production
US10377682B2 (en) 2014-01-09 2019-08-13 Siluria Technologies, Inc. Reactors and systems for oxidative coupling of methane
US9701597B2 (en) 2014-01-09 2017-07-11 Siluria Technologies, Inc. Oxidative coupling of methane implementations for olefin production
US10829424B2 (en) 2014-01-09 2020-11-10 Lummus Technology Llc Oxidative coupling of methane implementations for olefin production
US11208364B2 (en) 2014-01-09 2021-12-28 Lummus Technology Llc Oxidative coupling of methane implementations for olefin production
US10780420B2 (en) 2014-05-02 2020-09-22 Lummus Technology Llc Heterogeneous catalysts
US9956544B2 (en) 2014-05-02 2018-05-01 Siluria Technologies, Inc. Heterogeneous catalysts
US9751079B2 (en) 2014-09-17 2017-09-05 Silura Technologies, Inc. Catalysts for natural gas processes
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US11000835B2 (en) 2014-09-17 2021-05-11 Lummus Technology Llc Catalysts for natural gas processes
US9790144B2 (en) 2015-03-17 2017-10-17 Siluria Technologies, Inc. Efficient oxidative coupling of methane processes and systems
US10793490B2 (en) 2015-03-17 2020-10-06 Lummus Technology Llc Oxidative coupling of methane methods and systems
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US12227466B2 (en) 2021-08-31 2025-02-18 Lummus Technology Llc Methods and systems for performing oxidative coupling of methane

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CN86104014A (en) 1986-12-17
JPS62503101A (en) 1987-12-10
NO862377L (en) 1986-12-15
NZ216388A (en) 1990-01-29
EP0227750A4 (en) 1987-10-08
EP0227750A1 (en) 1987-07-08
ES8707705A1 (en) 1987-08-16
AU5994486A (en) 1987-01-07
NO862377D0 (en) 1986-06-13
ES556014A0 (en) 1987-08-16

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