JPS6238340B2 - - Google Patents

Description

[Detailed description of the invention]

[Object of the Invention] The present invention relates to a method for producing ethanol. More specifically, (a) a catalyst comprising at least one element selected from the group consisting of rhodium, lithium, iridium, and/or magnesium, yttrium, ytterbium, lutetium, vanadium, and chromium (hereinafter referred to as other additive elements) supported on a carrier; and (b) a method for producing ethanol by reacting carbon monoxide and hydrogen in the presence of a catalyst comprising iron supported. [Prior Art and Problems to be Solved by the Invention] Oxygen-containing compounds having two carbon atoms, such as ethanol and acetaldehyde, have conventionally been produced by a petrochemical method using naphtha as a raw material. However, due to the rise in crude oil prices in recent years, manufacturing prices have risen significantly.
The need for raw material conversion is emerging. On the other hand, various methods for producing oxygen-containing compounds having 2 carbon atoms from a mixed gas of carbon monoxide and hydrogen, which is abundant and available at low cost, have been studied. That is, a mixed gas of carbon monoxide and hydrogen, with rhodium as the main component, manganese, titanium, zircon,
A method for selectively producing an oxygen-containing compound having 2 carbon atoms by reacting it in the presence of a catalyst made of a metal such as iron or a metal oxide is known. (For example, JP-A No. 51-80806, No. 52-14706, No. 56-
(No. 147730, etc.) However, such methods produce a large amount of by-product hydrocarbons, such as methane, and when the selectivity of oxygen-containing compounds is low or the selectivity of oxygen-containing compounds is high, the amount produced is low. It was extremely low. Furthermore, the actual situation is that the amount of the target compound produced per rhodium, which is an expensive noble metal, is still small, and a technology that has been completed economically and process-wise has not been provided. Furthermore, with the aim of producing oxygen-containing compounds having 2 carbon atoms in high yield and with high selectivity, rhodium was combined with lithium (Japanese Patent Application Laid-Open No. 56-8334) and iron (Japanese Patent Application Laid-Open No. 51-8087).
Magnesium (Japanese Patent Publication No. 138504/1982), Vanadium (62232/1982), Yztrium, Ytterbium (62233/1983), Chromium (Japanese Patent Application No. 143918/1989), Rhodium and lithium and magnesium or vanadium etc. (JP-A-57-109734
No. 2) have been proposed, but all of these methods use acetaldehyde, acetic acid, or methanol as the main organisms, and have the drawback of extremely low ethanol yield and selectivity. As described above, no method has been provided for efficiently and economically producing an oxygen-containing compound containing ethanol as a main component from a gas containing carbon monoxide and hydrogen. The present inventors have proposed that when producing an oxygen-containing compound from a gas containing carbon monoxide and hydrogen, while improving the selectivity of the above-mentioned oxygen-containing compound having two carbon atoms, The present invention discloses a catalyst system that makes it possible to shift the distribution of oxygenated compounds into ethanol and minimize the production of hydrocarbons. As a result, by combining (a) a catalyst comprising at least one element selected from rhodium, lithium, iridium and/or other additive elements supported on a support, and (b) a catalyst comprising iron supported on a support. Unexpected effects were expressed, and the inventors discovered that ethanol has a preferable yield and high selectivity, leading to the completion of the present invention. [Summary of the Invention] As described above, the present invention provides (a) a catalyst comprising at least one element selected from rhodium, lithium, iridium and/or other additive elements supported on a carrier; and (b) iron supported on a support. Ethanol is produced by reacting carbon monoxide and hydrogen in the presence of a catalyst consisting of: The present invention will be explained in detail below. As mentioned above, the catalyst used in the present invention is
The two main catalysts are (a) a catalyst comprising at least one element selected from rhodium, lithium, iridium and/or other additive elements supported on a support, and (b) a catalyst comprising iron supported on a support. and other constituents. Both catalysts can be prepared separately, and when used, they should be mixed or mixed.
It is possible to use one of the catalysts in (a) in the upper layer and the iron catalyst in (b) in the lower layer. When preparing a catalyst, the above-mentioned components are usually dispersed on a carrier, as is done for noble metal catalysts. The catalyst used in the method of the present invention can be prepared according to conventional methods when using noble metals. For example, it can be prepared by an impregnation method, a dipping method, an ion exchange method, a coprecipitation method, a kneading method, etc. For rhodium and iridium, which are components of the catalyst, raw material compounds that can be used to prepare the catalyst include halides such as chloride and bromide;
Usually noble metal catalysts such as inorganic salts such as nitrates and carbonates, organic acid salts or chelate compounds such as acetates, oxalates, acetylacetonate salts, and ethylenediamine acetates, carbonyl compounds, ammine complexes, metal alkoxide compounds, alkyl metal compounds, etc. Compounds used in the preparation of can be used. Raw material compounds that can be used for lithium, magnesium, yttrium, ytterbium, lutetium, vanadium, and chromium used as promoters include halides, inorganic acid salts such as nitrates and chlorates, hydroxides, formates, and acetates. These organic acid salts, metal alkoxide compounds, alkyl metal compounds, etc. can be used as appropriate. In addition, raw material compounds that can be used as iron include inorganic salts such as halides, halogenates, and nitrates;
Organic acid salts such as formates and acetates, carbonyl compounds, etc. can be used as appropriate. However, in order to facilitate the loading of these catalyst components onto a support, compounds that are highly soluble in ethanol, water or other suitable solvents are preferably used. The method for preparing the catalyst will be explained below using the impregnation method as an example. The above metal compound is dissolved in a single or mixed solvent such as water, methanol, ethanol, acetone, tetrahydrofuran, dioxane, n-hexane, benzene, toluene, etc., a carrier is added to the solution, immersed, the solvent is distilled off, and the mixture is dried. If necessary, heating, gas treatment, etc. are performed to support the metal compound on the carrier. As a method for supporting the catalyst in (a) or (b), a mixed solution is prepared by dissolving the raw material compounds in the same solvent at the same time.
Various techniques may be used, including a method of simultaneously supporting each component on a carrier, a method of sequentially supporting each component, or a method of supporting each component sequentially or stepwise while carrying out treatments such as reduction and heat treatment as necessary. I can do it. Other preparation methods, such as a method in which metals are supported by ion exchange using the ion exchange ability of a carrier, and a method in which a catalyst is prepared by a coprecipitation method, are also adopted as methods for preparing the catalyst used in the method of the present invention. can. The catalysts (a) and (b) prepared by the above-mentioned method are usually activated by reduction treatment and then subjected to reaction. It is convenient and preferable to carry out the reduction using a hydrogen-containing gas at an elevated temperature. Although the reduction temperature of the catalyst (a) can be the temperature at which rhodium is reduced, that is, about 100°C, the reduction process is preferably carried out at a temperature of 200°C to 600°C. At this time, hydrogen reduction may be carried out while raising the temperature gradually or stepwise from a low temperature in order to sufficiently disperse each component of the catalyst. Further, reduction can also be carried out chemically using a reducing agent. For example, reduction treatment may be performed using carbon monoxide and water, or using a reducing agent such as hydrazine, a borohydride compound, or an aluminum hydride compound. Depending on the type of raw material compound, the iron catalyst (b) may be used simply by heat treatment, or may be subjected to reduction treatment in the same manner as the catalyst (a). As the carrier used in the present invention, those commonly known as carriers can be used as long as they preferably have a specific surface area of 10 to 1000 m ³ /g and a pore diameter of 10 Å or more. Specific carriers include silica, various silicates, alumina, activated carbon,
Examples include oxides of various metals (for example, zirconium oxide, titanium oxide, magnesia, etc.), molecular sheep, diatomaceous earth, etc., but silica-based carriers are preferred. The ratio of each component in the catalyst (a) above is as follows. The ratio of rhodium to carrier is 0.0001 to 0.5 by weight considering the specific surface area of the carrier.
Preferably it is 0.001 to 0.3. The ratio of lithium and rhodium is lithium/rhodium (atomic ratio)
It ranges from 0.0001 to 3, preferably from 0.0001 to 2. The ratio of iridium and rhodium is iridium/
Rhodium (atomic ratio) 0.001 to 6, preferably
It ranges from 0.005 to 3. The ratio of other additive elements to rhodium (other additive elements/rhodium (atomic ratio)) is in the range of 0.001 to 10, preferably 0.005 to 3. Furthermore, the ratio of iron used as the catalyst in (b) above is 0.0001 to 0.0001 by weight considering the specific surface area of the carrier.
1, preferably in the range of 0.005 to 0.5. The present invention can be applied, for example, to a fixed bed flow reactor. That is, the above (b) in the reactor
Fill the catalyst with one of the catalysts in (a) or fill it with a mixture of one of the catalysts in (a) and the catalyst in (b), and feed the raw material gas. Let the reaction take place. It is also possible to separate the product and recycle and reuse the unreacted raw material gas after purifying it if necessary. The present invention can also be applied to a fluidized bed type reactor. That is, it is also possible to carry out the reaction by mixing the raw material gas with one of the catalysts (a) and (b) and allowing a fluidized catalyst to accompany the mixture. Furthermore, the present invention can also be applied to a liquid phase heterogeneous reaction, which involves dispersing a catalyst in a solvent, feeding a raw material gas, and carrying out the reaction. The conditions adopted when carrying out the method of the present invention are various reaction conditions for the purpose of producing oxygen-containing compounds containing ethanol as the main component with high yield and high selectivity while minimizing the production of hydrocarbons. are selected by organically combining these factors. Although the target compound can be produced with high selectivity and high yield even at normal pressure (i.e. 0 kg/cm ² gauge), the reaction can be carried out under pressure to increase the space-time yield. . Therefore, the reaction pressure is 0 Kg/cm ² gauge to 350 Kg/cm ² gauge, preferably 0
Perform under pressure from Kg/cm ² gauge to 250Kg/cm ² gauge. Reaction temperature is 150℃~450℃, preferably 180℃
~350℃. When the reaction temperature is high, the amount of hydrocarbon by-product increases, so it is necessary to increase the feed rate of raw materials or change the composition ratio of hydrogen and carbon monoxide. Therefore, space velocity (raw material gas feed rate/
Catalyst capacity) is converted to standard conditions (0°C, 1 atm).
It is appropriately selected from the range of 10 h ^-1 to 10 ⁷ h ^-1 in relation to the reaction pressure, reaction temperature, and raw material gas composition. The composition of the raw material gas is a gas mainly containing carbon monoxide and hydrogen, and gases such as nitrogen, argon, helium, methane, etc., or hydrocarbons and dioxide if in a gaseous state under the reaction conditions. It may contain carbon, generated oxygen-containing compounds, and water. The mixing ratio of hydrogen and carbon monoxide is hydrogen/carbon monoxide (volume ratio) of 0.1 to 10, preferably 0.25 to 5, and the total proportion of carbon monoxide and hydrogen in the raw material gas is 20 to 100% by volume. Preferably 60~
It is 100% by volume. The present invention will be explained in more detail with reference to Examples below, but these Examples are deliberately shown under the same reaction conditions in order to facilitate understanding of the present invention.
It goes without saying that the present invention is not limited to this in any way. Example 1 1.20 g of rhodium chloride (RhCl _{3.3H 2} O), 0.093 g of magnesium chloride (MgCl _{2.6H 2} O), and 0.055 g of lithium chloride (LiCl.H ₂ O) were dissolved in 30 ml of ethanol, and silica gel was added to the solution. (DAVISON#57)
After adding 25 ml, it was dried under reduced pressure using a rotary evaporator. This supported catalyst was packed into a Pyrex glass reaction tube and reduced at 400° C. for 5 hours under 180 ml of hydrogen per minute to prepare a Rh-Mg-Li catalyst. Also, add 0.272 g of iron chloride (FeCl ₂ 4H ₂ O) to water.
After dissolving it in 11.5 ml and adding 25 ml of the silica gel described above, it was dried and reduced in the same manner as above to prepare an Fe catalyst. Activity test and results A titanium reaction tube with an inner diameter of 14 mm and a thermocouple protection tube with an outer diameter of 6 mm was filled with 4 ml of the above Fe catalyst, and then 4 ml of the above Rh-Mg-Li catalyst was diluted with 10 ml of the silica gel described above. and filled it. The inside of the reaction tube was replaced with nitrogen and heated at 200°C with nitrogen-diluted hydrogen gas (H ₂ :N ₂ = 100:100ml/min) under normal pressure.
After re-reducing for 1 hour, hydrogen/carbon monoxide = 2/1
A mixed gas of (volume ratio) was fed at 36 N/hour, and the reaction was carried out at a reaction pressure of 20 Kg/cm ² and a reaction temperature of 275°C. Of the reaction effluent, the liquid product was absorbed and collected in water, and the effluent gas composition was analyzed by gas chromatography, and the results are shown in Table 1. Example 2 1.20 g of rhodium chloride, 0.138 g of yttrium chloride (YCl ₃ 6H ₂ O), and 0.055 g of lithium chloride were dissolved in 30 ml of ethanol, and 25 ml of the silica gel described above was added thereto, followed by the same procedure as in Example 1. The experiment was carried out using 4 ml of Rh-Y-Li catalyst prepared by drying and reduction treatment in the same manner as in Example 1, and 4 ml of Fe catalyst prepared in the same composition ratio as in Example 1. It was charged and reacted in the same manner as in Example 1. The results are shown in Table 1. Example 3 Rhodium chloride 1.20g, yzterbium chloride (YbCl ₃ 6H ₂ O) 0.177g, lithium chloride 0.055g
was dissolved in 30 ml of ethanol, 25 ml of the silica gel described above was added thereto, and 4 ml of Rh-Yb-Li catalyst was prepared by using the same apparatus as in Example 1 and drying and reducing in the same manner. Then, 4 ml of Fe catalyst prepared in the same manner as in Example 1 with the same composition ratio was used, and the reaction was carried out in the same manner as in Example 1. The results are shown in Table 1. Example 4 Rhodium chloride 1.20g, lutetium chloride (LuCl ₃ 6H ₂ O) 0.178g, lithium chloride 0.055g
was dissolved in 30 ml of ethanol, 25 ml of the silica gel described above was added thereto, and 4 ml of Rh-Lu-Li catalyst was prepared by using the same apparatus as in Example 1 and drying and reducing in the same manner. and 4 ml of Fe catalyst prepared in the same manner as in Example 1 with the same composition ratio.
was charged in the same manner as in Example 1, and the reaction was carried out. The results are shown in Table 1. Example 5 Rhodium chloride 1.20g, vanadium chloride (VCl ₃ )
0.072g, lithium chloride 0.055g in ethanol 30ml
Add 25 ml of the silica gel described above to this.
Rh-V was prepared using the same equipment as in Example 1 and drying and reduction treatment in the same manner as in Example 1.
A reaction was carried out in the same manner as in Example 1 using 4 ml of -Li catalyst and 4 ml of Fe catalyst prepared in the same composition ratio as in Example 1. The results are shown in Table 1. Example 6 Rhodium chloride 1.20g, chromium chloride ( _CrCl3 .
0.122 g of 6H ₂ O) and 0.055 g of lithium chloride were dissolved in 30 ml of ethanol, and 25 ml of the silica gel described above was added thereto. Using the same apparatus as in Example 1, drying was carried out in the same manner. prepared by processing
A reaction was carried out in the same manner as in Example 1 using 4 ml of Rh-Cr-Li catalyst and 3 ml of Fe catalyst prepared in the same composition ratio as in Example 1. The results are shown in Table 1. Example 7 Rhodium chloride 1.20g, lutetium chloride 0.178
g, 0.055 g of lithium chloride, and 0.064 g of iridium chloride (IrCl ₄ H ₂ O) were dissolved in 30 ml of ethanol, and after adding 25 ml of the silica gel described above, using the same apparatus as in Example 1, Filled in the same manner as in Example 1 using 4 ml of Rh-Lu-Li catalyst prepared by drying and reduction treatment in the same manner and 4 ml of Fe catalyst prepared in the same composition ratio as in Example 1. Then, the reaction was carried out. The results are shown in Table 1. Example 8 Rhodium chloride 1.20g, vanadium chloride 0.072
g, lithium chloride 0.055g, iridium chloride 0.064
After dissolving 0.055 g of 0.05 g in 30 ml of ethanol and adding 25 ml of the silica gel described above, drying was carried out in the same manner using the same equipment as in Example 1.
4ml of Rh-V-Li-Ir catalyst prepared by reduction treatment
Then, using 4 ml of Fe catalyst prepared in the same manner as in Example 1 and having the same composition ratio, the reactor was charged and reacted in the same manner as in Example 1. The results are shown in Table 1. Comparative Example 1 Rh-
A reaction was carried out in the same manner as in Example 1, except that a Mg-Li catalyst was prepared and 4 ml of it was diluted with 10 ml of the silica gel described above and charged. The results are shown in Table 1. Comparative Example 2 Rh-
The reaction was carried out in the same manner as in Example 1, except that a Y-Li catalyst was prepared and 4 ml of it was diluted with 10 ml of the silica gel described above and charged. The results are shown in Table 1. Comparative Example 3 Rh-
A reaction was carried out in the same manner as in Example 1, except that a Yb-Li catalyst was prepared and 4 ml of it was diluted with 10 ml of the silica gel described above and charged. The results are shown in Table 1. Comparative Example 4 Rh-
The reaction was carried out in the same manner as in Example 1, except that a Lu-Li catalyst was prepared and 4 ml of it was diluted with 10 ml of the silica gel described above and charged. The results are shown in Table 1. Comparative Example 5 Rh-
The reaction was carried out in the same manner as in Example 1, except that a V-Li catalyst was prepared and 4 ml of it was diluted with 10 ml of the silica gel described above and charged. The results are shown in Table 1. Comparative Example 6 Rh-
A reaction was carried out in the same manner as in Example 1, except that a Cr-Li catalyst was prepared and 4 ml of it was diluted with 10 ml of the silica gel described above and charged. The results are shown in Table 1.

【table】

[Table] Example 9 After mixing and filling 4 ml of the Rh-V-Li catalyst prepared in Example 5 and 4 ml of the Fe catalyst prepared in Example 1 with 10 ml of the silica gel described above, the mixture was prepared in the same manner as in Example 1. The reaction was carried out. The results are shown in Table 2. Example 10 4 ml of Rh-V-Li-Ir catalyst prepared in Example 8
After mixing and filling 4 ml of the Fe catalyst prepared in Example 1 with 10 ml of the silica gel described above,
The reaction was carried out in the same manner as in Example 1. Second result
Shown in the table. Comparative example 7 Rhodium chloride 1.20g, vanadium chloride 0.072
g, 0.055 g of lithium chloride, and 0.272 g of iron chloride were dissolved in 40 ml of ethanol, and 25 ml of the silica gel described above was added thereto. Using the same apparatus as in Example 1, the mixture was dried and reduced in the same manner. TeRh-V-
A Li-Fe catalyst was prepared. A reaction was carried out in the same manner as in Example 1, except that 4 ml of the Rh-V-Li-Fe catalyst diluted with 10 ml of the silica gel described above was charged into the same reaction apparatus as in Example 1. The results are shown in Table 2.

【table】

【table】

Claims (1)

[Claims] 1. A catalyst comprising at least one element selected from rhodium, lithium, iridium, and/or magnesium, yttrium, ytterbium, lutetium, vanadium, and chromium supported on a carrier;
A method for producing ethanol, which comprises reacting carbon monoxide and hydrogen in the presence of a catalyst comprising iron supported on a carrier.