CN104549465B

CN104549465B - Heavy aromatics lightening catalyst of voluminous dimethylbenzene and preparation method thereof

Info

Publication number: CN104549465B
Application number: CN201310512218.0A
Authority: CN
Inventors: 孔德金; 李旭光; 郑均林; 姜向东
Original assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Current assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Priority date: 2013-10-28
Filing date: 2013-10-28
Publication date: 2017-07-14
Anticipated expiration: 2033-10-28
Also published as: CN104549465A

Abstract

The present invention relates to heavy cyclophane lightening catalyst of a kind of voluminous dimethylbenzene and preparation method thereof, mainly heavy aromatics conversion level present in solution prior art is low, low and selective low, the problem of catalyst deactivation rate is fast of dimethylbenzene yield.The present invention includes the mixture of 30~60%MFI types zeolite and the molecular sieves of ZSM 12 by weight percentage by using catalyst, 38.5~69.8% at least one in gamma-alumina, η aluminum oxide or boehmite is binding agent, the technical scheme of 0.1~0.5% at least one metal in Pt, Pd or Ir and 0.1~1% at least one metal in Zn, La, Ce or Bi, the problem is preferably solved, the catalyst is converted into the industrial production of mononuclear aromatics increasing production of xylol available for heavy polycyclic aromatic hydrocarbon.

Description

Heavy aromatics lightening catalyst of voluminous dimethylbenzene and preparation method thereof

Technical field

The present invention relates to a kind of heavy aromatics lightening catalyst of voluminous dimethylbenzene and preparation method thereof.

Background technology

Oil is important earth resource for the survival of mankind, and the clothing, food, lodging and transportion -- basic necessities of life with people are closely related.But by the world In the range of limited petroleum resources and produce the continuous intensification of oil product degree of heaviness in recent years, force the people must be to this A little mink cell focuses are reasonably comprehensively utilized.The annual production of heavy aromatics increases year by year, in addition to a seldom part is used as organic solvent, Major part, which is impregnated in fuel, to be used, no matter from environmental protection or economic angle, and Heavy Aromatic Hydrocarbons are not all by effectively comprehensive profit With.Angularly consider from the market demand, production cost and environmental requirement, the organic of high added value is developed using these heavy aromatics Industrial chemicals is an important developing direction.The light aromatic hydrocarbons such as benzene,toluene,xylene are all important Organic Chemicals, benzene It is the basic material for preparing the products such as styrene, nylon, terylene；And to be used as the blending compound of gasoline pungent to improve for toluene Alkane value, can also produce paint, binding agent, organic solvent etc. in industry, agricultural and medically be widely used；Dimethylbenzene then many quilts For producing the products such as polyester, chemical fibre, the demand of market paraxylene be also it is growing day by day, its importance in aromatic hydrocarbon resource with Benzene is suitable.In recent years, heavy aromatics turns into the valuable source of production light aromatic hydrocarbons, and heavy aromatics takes off alkyl technology as raising heavy aromatics The important means of utilization rate and the regulation dimethylbenzene equilibrium of supply and demand, increasingly causes the concern of domestic and foreign scholars.

Uop Inc. develops arene stream and is first hydrocracked, will be enriched in benzene, toluene and C again₉ ⁺Hydrogenation logistics carry out alkyl The technique (WP2009008876, publication date on January 15th, 2009) of transfer production dimethylbenzene, what the technique was used, which be hydrocracked, urges Agent is the amorphous silicon aluminium catalyst containing VIII or group vib metal, reaction condition is 232~468 DEG C, 3.5~ 20.8MPa, LHSV are 0.1~30h^-1.Alkylation reaction condition is 200~525 DEG C, LHSV is 0.2~10h^-1, using containing non- MCM-22, MOR, FAU type molecular sieve catalyst of framework metal, wherein molecular sieve account for 30~50wt%.

USP4,341,622 discloses a kind of method that utilization heavy reformate produces BTX.This method uses restricted index It is catalyst for the zeolite that 1~12, silica/alumina molar ratio (silica alumina ratio) is more than 12, low acid activity, reformate is existed Reacted under conditions of 427~540 DEG C, then product separated is obtained into benzene, toluene and dimethylbenzene.Described catalyst contains The VIII noble metal of hydro-dealkylation function, preferably platinum, the silica alumina ratio of zeolite used are preferably greater than 200, more preferably greater than 500, zeolite preferably is ZSM-5.It is reduction zeolite acidity to select the zeolite of high silica alumina ratio, and dimethylbenzene is retained as far as possible in reaction In be not converted.

CN1934058A discloses a kind of by dihydroindene and C₁₀It is C Deng polycyclic aromatic hydrocarbon conversion and transalkylation₈Aromatic hydrocarbons Method, the catalyst that this method is used includes solid acid carrier (such as：Modenite) and metal component is (such as：Rhenium), can be by this Method produces valuable dimethylbenzene.

CN200580009162 discloses a kind of method that polycyclic aromatic hydrocarbon is catalytically conveted to dimethylbenzene, and what this method was used urges Agent carrier is selected from modenite, mazzite, β zeolites, the topological zeolite of ZSM-11, ZSM-12, ZSM-22, ZSM-23, MFI, NES Topological zeolite, EU-1, MAPO-36, MAPSO-31, SAPO-11, SAPO-41 and silica-alumina and combinations thereof.Should Catalyst can be used for raw material stream of the processing containing high boiling substance, and raw material can also be reduced to a certain degree while dimethylbenzene is generated The 99.5wt% of stream terminal.

The content of the invention

One of technical problems to be solved by the invention be in order to overcome catalyst present in prior art be used for heavy Heavy aromatics conversion level is low when polycyclic aromatic hydrocarbon is converted into mononuclear aromatics reaction, and dimethylbenzene yield is low and selectivity is low, and catalyst loses There is provided a kind of new heavy aromatics lightening catalyst for voluminous dimethylbenzene for the problem of speed of living is fast.The catalyst is used for weight Aromatic hydrocarbons is converted into the reaction of mononuclear aromatics, high with heavy aromatics conversion level, and the yield and selectivity of dimethylbenzene are high, and catalyst loses The slow advantage of speed living.

The two of the technical problems to be solved by the invention are to provide a kind of with solving one of technical problem corresponding fecund The preparation method of the heavy aromatics lightening catalyst of dimethylbenzene.

The three of the technical problems to be solved by the invention are to provide a kind of with solving one of technical problem corresponding fecund The purposes of the heavy aromatics lightening catalyst of dimethylbenzene.

To solve one of above-mentioned technical problem, the technical solution adopted by the present invention is as follows：A kind of weight virtue of voluminous dimethylbenzene Hydrocarbon lightening catalyst, in terms of catalyst weight percent, including following components：

A) mixture of 30~60% MFI type zeolites and ZSM-12 molecular sieves；

B) 38.5~69.8% at least one in gama-alumina, η-aluminum oxide or boehmite is bonding Agent；

C) 0.1~0.5% at least one metal or its oxide in Pt, Pd or Ir；

D) 0.1~1% at least one metal or its oxide in Zn, La, Ce or Bi.

In above-mentioned technical proposal, MFI type zeolite and ZSM-12 molecular sieves are Hydrogen or ammonium type in used catalyst composition, Sodium weight content is less than 2%；The amount preferred scope of MFI type zeolite is 35~70%, ZSM-12 by weight percentage in mixture The amount preferred scope of molecular sieve is 30~65%.

To solve the two of above-mentioned technical problem, the technical solution adopted by the present invention is as follows：A kind of weight virtue of voluminous dimethylbenzene The preparation method of hydrocarbon lightening catalyst, comprises the following steps：

1. by the mixture of the desired amount of MFI type zeolite and the desired amount of ZSM-12 molecular sieves with it is the desired amount of selected from γ- At least one binding agent in aluminum oxide, η-aluminum oxide or boehmite is carried out after kneading, shaping, drying, 450~ 650 DEG C of 0.5~24h of roasting obtain catalyst carrier；

2. by the precursor solution and institute of the desired amount of at least one metal in Pt, Pd or Ir or its oxide At least one metal in Zn, La, Ce or Bi of requirement or the precursor solution of its oxide it is well mixed after 30~ 50 DEG C are impregnated into 0.5~24h in catalyst carrier, and 0.5~24h is calcined at 300~450 DEG C after drying obtains finished product catalysis Agent.

In above-mentioned technical proposal, preferred scheme is in catalyst carrier preparation process, addition by carrier butt calculate 2~ The extrusion aid of 5% weight, extrusion aid is at least one in sesbania powder or tung oil；Addition by carrier dry basis 3~6% into Jelly, at least one and water volume ratio 1 of the gelatinizing agent in hydrochloric acid, nitric acid, acetic acid, tartaric acid, citric acid or oxalic acid：1~ 1：5.

The precursor solution preferred scheme of Pt metal used is chloroplatinic acid in above-mentioned technical proposal；The predecessor of metal Pd Solution preferred scheme is at least one in palladium nitrate or palladium bichloride；Metal Ir precursor solution preferred scheme is chloro-iridic acid； Metal Zn used predecessor preferred scheme is at least one in zinc oxide, zinc chloride or zinc nitrate；Metal La forerunner Thing solution preferred scheme is at least one in lanthanum nitrate or carbonic acid bright-coloured；Metal Ce precursor solution preferred scheme is that nitric acid is sub- Cerium；Metal Bi precursor solution preferred scheme is at least one in bismuthic oxide or bismuth oxide.

To solve the three of above-mentioned technical problem, the technical solution adopted by the present invention is as follows：A kind of side of heavy aromatics lighting Method, raw material heavy aromatics mixture is mixed with hydrogen, passes through beds, in 340 ~ 420 DEG C of reaction temperature, instead Answer the MPa of pressure 4 ~ 7, the hr of weight (hourly) space velocity (WHSV) degree 1 ~ 8^-1, under the conditions of hydrogen/hydrocarbon mol ratio 5.0 ~ 8.0 with it is above-mentioned any one Described catalyst contact, heavy aromatics is converted into the mononuclear aromatics comprising benzene,toluene,xylene.

In above-mentioned technical proposal, technical scheme preferably is, reaction temperature is 350 ~ 380 DEG C, reaction pressure is 5 ~ 6 MPa, weight (hourly) space velocity (WHSV) degree are 1 ~ 2 hr^-1, hydrogen/hydrocarbon mol ratio be 6.0 ~ 7.0.

The catalyst that the present invention is provided can be used for heavy polycyclic aromatic hydrocarbon to be converted into the industrial raw of mononuclear aromatics increasing production of xylol In production.

Due to have selected the ZSM-12 molecular sieves for containing macropore as catalyst acid center in the present invention, be conducive to heavy The acid site that aromatic hydrocarbons macromolecular enters in duct carries out ring-opening reaction, and the product molecule after conversion can quickly be expanded by duct Dissipate, not only improve the conversion capability of heavy aromatics, and delayed the deactivation rate of catalyst；Another support acidity component MFI type Zeolite possesses good transalkylation and de- alkyl functional, then by loading the precious metal element with hydrogenating function, controls it Load capacity can effectively improve the yield and selectivity of dimethylbenzene in aromatic product in a zone of reasonableness；The introducing of aided metal The decentralization of carried noble metal can be improved, delays accumulation of metal to grow up, the service life of catalyst can be effectively improved；Catalysis The rational proportion of agent acid site and metallic element is carried while will retaining original mononuclear aromatics component in raw material stream as far as possible The yield of high wherein dimethylbenzene, achieves preferable technique effect.

The reactivity worth that the present invention carries out heavy aromatics lighting using overcritical fixed bed reactors is investigated, reactor inside diameter 12 millimeters of Ф, 800 millimeters of length, stainless steel.Using electrical heating, temperature automatic control.Reactor bottom fills Ф 2~3 Millimeter bead is 5 grams of catalyst filling in supporter, reactor, and filling 2~3 millimeters of beades of Ф in top are made for raw material pre- Heat and vaporization are used.Raw material heavy aromatics mixture is mixed with hydrogen, passes through beds, in reaction temperature 340 ~ 420 DEG C, the MPa of reaction pressure 4 ~ 7, the hr of weight (hourly) space velocity (WHSV) degree 1 ~ 8^-1, under conditions of hydrogen/hydrocarbon mol ratio 5.0 ~ 8.0 with urging Agent is contacted, and heavy aromatics is converted into the mononuclear aromatics mixture of voluminous dimethylbenzene.

Heavy aromatics mixture is autogamy raw material, and experimental data is calculated as follows.

Below by embodiment, the present invention is further elaborated.

Embodiment

【Embodiment 1】

It is 25 g ZSM-5 zeolites (commercially available ammonium type), 25 g ZSM-12 molecular sieves (commercially available Hydrogen) and 50 g by butt γ-Al₂O₃(industrial goods) add blender to uniform, and 3 g sesbania powders, 5 g volume ratios 1 are then added into mixture:1 HNO₃Solution and 40 g deionized waters, the uniform dough being made suitable for extrusion of grinding.It is extruded by mould, shape is in elongated Cylinder (mm of diameter 1.7), 120 DEG C drying after 550 DEG C be calcined 4 h, be then cut into the consistent carrier of size Grain (1.7 × 4.0 mm), is designated as Z1.

Chloroplatinic acid and zinc oxide wiring solution-forming are impregnated at 40 DEG C to carrier granular, the amount containing Pt is in maceration extract 0.2%, Zn of carrier butt weight amount is 0.2%, dipping 8h and after drying, and 3 h are calcined at 450 DEG C, and finished product is catalyzed Agent A.

【Embodiment 2~10】

The preparation method and process provided according to embodiment 1, by changing metal front in carrier composition and maceration extract The species and content of thing, are prepared for a series of finished catalysts, are shown in Table 1.

Table 1

【Embodiment 11~19】

With catalyst A~J (highest response pressure on overcritical fixed bed reactors made from embodiment 1~10 10MPa, temperature in use are room temperature~600 DEG C) investigate and heavy aromatics mixture is converted into BTX (wherein B is benzene, and T is toluene, and X is Dimethylbenzene) etc. mononuclear aromatics ability.Table 2 constitutes to evaluate raw material.The g of Catalyst packing 5, in 360 DEG C of reaction temperature, reaction Pressure 5.0MPa, weight (hourly) space velocity (WHSV) degree 2.0hr^-1, contacted with catalyst under the conditions of hydrogen/hydrocarbon mol ratio 6.0, product is carried out Reclaim and component detection, conversion results are shown in Table 3.

Table 2

Raw material is constituted	It is non-aromatic	Benzene	Toluene	Ethylbenzene	Dimethylbenzene	Decahydronaphthalene	Naphthane	Naphthalene
									Content (wt%)	0.02	24.54	24.61	5.00	0.02	14.81	15.25	15.75

Table 3

Catalyst is numbered	Total conversion (wt%)	BTX selectivity (wt%)	X selectivity (wt%)
				A	67.3	60.2	30.8
B	69.5	59.1	28.6
				C	67.0	59.5	29.5
D	68.4	60.0	30.1
				E	67.1	59.2	29.0
F	63.8	62.5	32.3
				G	65.6	61.4	31.7
H	68.1	60.1	29.9
				I	62.5	65.3	33.3
J	69.3	59.1	28.3

【Embodiment 20~24】

Investigated heavy aromatics mixture with catalyst A~E made from embodiment 1~5 on overcritical fixed bed reactors It is converted into the ability of the mononuclear aromatics such as BTX.The g of Catalyst packing 5, in 380 DEG C of reaction temperature, reaction pressure 6MPa, weight (hourly) space velocity (WHSV) Spend 1.0 hr^-1, contacted with catalyst under the conditions of hydrogen/hydrocarbon mol ratio 6.0, product is reclaimed and component detection, will Conversion results are shown in Table 4.

Table 4

Catalyst is numbered	Total conversion (wt%)	BTX selectivity (wt%)	X selectivity (wt%)
				A	68.9	62.8	32.0
B	70.5	61.3	30.9
				C	68.5	62.9	32.5
D	73.1	62.0	31.4
				E	72.6	62.4	32.1

【Embodiment 25~29】

Investigated heavy aromatics mixture with catalyst A~E made from embodiment 1~5 on overcritical fixed bed reactors It is converted into the ability of the mononuclear aromatics such as BTX.The g of Catalyst packing 5, in 360 DEG C of reaction temperature, reaction pressure 6MPa, weight (hourly) space velocity (WHSV) Spend 2.0 hr^-1, contacted with catalyst under the conditions of hydrogen/hydrocarbon mol ratio 7.0, product is reclaimed and component detection, will Conversion results are shown in Table 5.

Table 5

Catalyst is numbered	Total conversion (wt%)	BTX selectivity (wt%)	X selectivity (wt%)
				A	67.9	61.0	30.6
B	70.0	59.7	29.2
				C	67.5	60.2	30.0
D	69.3	60.9	30.6
				E	67.8	59.9	30.0

【Embodiment 30~34】

Investigated heavy aromatics mixture with catalyst A~E made from embodiment 1~5 on overcritical fixed bed reactors It is converted into the ability of the mononuclear aromatics such as BTX.The g of Catalyst packing 5, in 360 DEG C of reaction temperature, reaction pressure 6MPa, weight (hourly) space velocity (WHSV) Spend 3.0 hr^-1, contacted with catalyst under the conditions of hydrogen/hydrocarbon mol ratio 6.0, product is reclaimed and component detection, will Conversion results are shown in Table 6.

Table 6

Catalyst is numbered	Total conversion (wt%)	BTX selectivity (wt%)	X selectivity (wt%)
				A	64.3	60.5	31.0
B	65.5	59.7	29.1
				C	64.1	59.8	29.4
D	65.2	60.3	30.0
				E	64.6	59.5	29.6

【Embodiment 35~39】

Investigated heavy aromatics mixture with catalyst A~E made from embodiment 1~5 on overcritical fixed bed reactors It is converted into the ability of the mononuclear aromatics such as BTX.The g of Catalyst packing 5, in 370 DEG C of reaction temperature, reaction pressure 5MPa, weight (hourly) space velocity (WHSV) Spend 2.0 hr^-1, contacted with catalyst under the conditions of hydrogen/hydrocarbon mol ratio 6.0, product is reclaimed and component detection, will Conversion results are shown in Table 7.

Table 7

Catalyst is numbered	Total conversion (wt%)	BTX selectivity (wt%)	X selectivity (wt%)
				A	69.1	62.2	31.5
B	70.9	60.6	30.6
				C	68.7	62.5	32.0
D	70.4	60.3	29.9
				E	69.5	61.8	30.7

Claims

1. a kind of heavy aromatics lightening catalyst of voluminous dimethylbenzene, in terms of catalyst weight percent, including following components：

A) MFI type zeolite by weight percentage in the mixture of 30~60%MFI types zeolite and ZSM-12 molecular sieves, mixture Amount be that the amounts of 35~70%, ZSM-12 molecular sieves is 30~65%；

B) 38.5~69.8% at least one in gama-alumina, η-aluminum oxide or boehmite is binding agent；

C) 0.1~0.5% at least one metal or its oxide in Pt, Pd or Ir；

D) 0.1~1% at least one metal or its oxide in Zn or Bi.

2. the heavy aromatics lightening catalyst of voluminous dimethylbenzene according to claim 1, it is characterised in that MFI type zeolite and ZSM-12 molecular sieves are Hydrogen or ammonium type, and sodium weight content is less than 2%.

3. the preparation method of the heavy aromatics lightening catalyst of the voluminous dimethylbenzene described in claim 1, comprises the following steps：

1. the mixture of the desired amount of MFI type zeolite and the desired amount of ZSM-12 molecular sieves is selected from gamma oxidation with the desired amount of At least one binding agent in aluminium, η-aluminum oxide or boehmite is carried out after kneading, shaping, drying, at 450~650 DEG C 0.5~24h of roasting obtains catalyst carrier；

2. by the precursor solution of the desired amount of at least one metal in Pt, Pd or Ir or its oxide and the desired amount of Well mixed be impregnated into after 30~50 DEG C of the precursor solution of at least one metal or its oxide in Zn or Bi is urged 0.5~24h on agent carrier, is calcined 0.5~24h at 300~450 DEG C after drying and obtains finished catalyst.

4. the preparation method of the heavy aromatics lightening catalyst of voluminous dimethylbenzene according to claim 3, it is characterised in that The extrusion aid of carrier dry basis 2~5% is pressed in addition in catalyst carrier preparation process；Add in catalyst carrier preparation process Plus at least one acid solution in hydrochloric acid, nitric acid, acetic acid, tartaric acid, citric acid or oxalic acid is gelatinizing agent.

5. the preparation method of the heavy aromatics lightening catalyst of voluminous dimethylbenzene according to claim 4, it is characterised in that Extrusion aid is at least one in sesbania powder or tung oil.

6. the preparation method of the heavy aromatics lightening catalyst of voluminous dimethylbenzene according to claim 4, it is characterised in that With carrier dry basis, 3~6 weight % added in catalyst carrier preparation process gelatinizing agent, in gelatinizing agent, selected from salt At least one and water volume ratio in acid, nitric acid, acetic acid, tartaric acid, citric acid or oxalic acid is 1：1~1：5.

7. the preparation method of the heavy aromatics lightening catalyst of voluminous dimethylbenzene according to claim 3, it is characterised in that The precursor solution of described Pt metal is chloroplatinic acid；The precursor solution of metal Pd is at least one in palladium nitrate or palladium bichloride Kind；Metal Ir precursor solution is chloro-iridic acid.

8. a kind of method of the heavy aromatics lighting of voluminous dimethylbenzene, raw material heavy aromatics mixture is mixed with hydrogen, from top to bottom By beds, in 350~380 DEG C of reaction temperature, 5~6MPa of reaction pressure, 1~2hr of weight (hourly) space velocity (WHSV) degree^-1, hydrogen/hydrocarbon rubs You than 6.0~7.0 under the conditions of contacted with the catalyst described in any one in claim 1~2, heavy aromatics, which is converted into, to be included The mononuclear aromatics of benzene,toluene,xylene.