CN100486701C - Liquid phase reaction process of methyl acetate and CO to produce acetic anhydride and its catalyst preparing process - Google Patents
Liquid phase reaction process of methyl acetate and CO to produce acetic anhydride and its catalyst preparing process Download PDFInfo
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- CN100486701C CN100486701C CNB2006101306486A CN200610130648A CN100486701C CN 100486701 C CN100486701 C CN 100486701C CN B2006101306486 A CNB2006101306486 A CN B2006101306486A CN 200610130648 A CN200610130648 A CN 200610130648A CN 100486701 C CN100486701 C CN 100486701C
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Abstract
The present invention is the preparation process of acetic anhydride through liquid phase reaction of methyl acetate and CO and the preparation process of its catalyst. The catalyst has Rh-Pd complex with Rh/Pd weight ratio of 4-5 as the active component in 2.0-5.0 wt%, ethyl iodide or methyl bromide as co-catalyst in 0.5-9.5 wt%, and carrier of ZSM or MCM molecular sieve in 30.0-40.0 wt%. The catalyst is prepared through dissolving soluble compound of the catalyst and co-catalyst to obtain solution, soaking the carrier inside the solution, high temperature roasting at 500.0-600.0 deg.c for 1.0-1.5. The catalyst is used in preparing acetic anhydride through liquid phase reaction of methyl acetate and CO and can result in high methyl acetate converting rate and acetic anhydride yield. The present invention provides one new industrial production way.
Description
Technical field
The invention belongs to the method for chemical reaction.Relate to preparation technology and method for preparing catalyst thereof that a kind of methyl acetate and carbon monoxide liquid phase carbonyl generate aceticanhydride (acetic anhydride).
Background technology
Aceticanhydride is the abbreviation of acetic anhydride, the formal name used at school acetic anhydride.It is a kind of water white liquid, has penetrating odor, strong tearing property is arranged; it is a kind of important Organic Chemicals; chemical property is very active, is widely used in producing the production of cellulose acetate and as the acetylizing agent in medicine, dyestuff, spices and the organic synthesis.The production of aceticanhydride is the ketene process based on acetic acid and acetone at first, is the oxidation of acetaldehyde co-production method then.Though the ketene process technology maturation, its flow process complexity and side reaction are more, and process energy consumption and equipment investment are all bigger; The oxidation of acetaldehyde co-production method has that flow process is simple, technical maturity but its corrosion of equipment is serious, energy consumption is bigger.Method synthetic with the gas phase carbonyl at present and the synthetic production of liquid phase carbonyl aceticanhydride has the advantages that flow process is simple, the process energy consumption is lower and side reaction is less, and by the calculation of thermodynamics feasibility of course of reaction as can be known, obviously this is a technical process with practicality and novelty, has better industrial application prospect.Following data provides the background information of relevant aceticanhydride synthesis technique.
Chinese patent CN 1778468A discloses the catalyst system and the application of catalytic methylester acetate or the synthetic aceticanhydride of dimethyl ether, its active component is a rhodium complex, co-catalyst is alkyl iodide, phosphate and alkali metal salt compounded of iodine, the conversion ratio of methyl acetate is 49.8～51.2%, and the aceticanhydride space-time yield is 12.1～15.5mol/ (L.h).
Chinese patent CN 1612850A discloses the integral method that is generated carbonylation acetate, acetic anhydride or coproduction of each by the ethyl acetate accessory substance, be to utilize by-product methyl acetate in the polyvinyl alcohol production process to generate the method for acetate and acetic anhydride, the conversion ratio of methyl acetate is 39.0～43.0%, and the aceticanhydride space-time yield is 13.1～16.5mol/ (L.h).
Chinese patent CN 1039410A discloses the synthetic method of acetate and acetic anhydride, generate acetate and acetic anhydride under the catalyst condition that adopts VIII family carbonyls, methyl iodide and alkali metal acetate to form, the conversion ratio of methyl acetate is 38.0～42.0%, and the aceticanhydride space-time yield is 12.1～15.5mol/ (L.h).
Chinese patent CN 1039410A discloses under rhodium catalyst and co-catalyst the synthetic method for preparing acetic anhydride or acetic anhydride and acetate mixture of methyl acetate gas phase carbonyl, the conversion ratio of methyl acetate is 34.0～39.0%, and the aceticanhydride space-time yield is 8.1～11.5mol/ (L.h).
Document (the research that the aceticanhydride carbonyl is synthetic, Coal Chemical Industry, 2001,95 (2): 21-25) disclose a kind of novel multidentate quaternary salt and heterodesmic mould assembly rhodium complex catalyst of utilizing and made methyl acetate carry out the technology of the acetic acid synthesized and acetic anhydride of liquid phase carbonyl, its catalytic rate and space-time yield are all greater than external existing industrial level.
United States Patent (USP) UP4618460 discloses a kind of methyl acetate and carbon monoxide of utilizing under the carboxylic acid condition, the process of the composite catalyst synthesis of acetic acid acid anhydride of forming with nickel, methyl iodide and sodium iodide, methyl acetate process conversion ratio can reach 50.0～60.0%, and the aceticanhydride space-time yield is 24.1～37.5mol/ (L.h).
United States Patent (USP) UP4374070 discloses the process of composite catalyst oxo-acetic anhydride under HTHP of forming with rhodium, iodide and lithiumation thing under a kind of hydrogen condition that adds 2-7% percent by volume in the carbonyl reaction device, the conversion ratio of methyl acetate is 42.0～62.0%, and the aceticanhydride space-time yield is 30.1～45.5mol/ (L.h).
European patent EP 0350635 disclose a kind of methyl acetate in adding the hydrogen of 5% percent by volume under the composite catalyst of rhodium and nickel, alkyl iodide and phosphate composition the process of gas phase carbonyl synthesis acetic acid and aceticanhydride, the conversion ratio of methyl acetate is 44.0～49.2%, and the aceticanhydride space-time yield is 25.1～29.5mol/ (L.h).
Japan Patent JP8-20555 has introduced technology and the catalyst thereof that utilizes methyl acetate and carbon monoxide to generate aceticanhydride under a kind of high pressure under rhodium plutonium catalyst, the conversion ratio of its process methyl acetate is 43.0～56.0%, and the aceticanhydride space-time yield is 31.1～38.5mol/ (L.h).
In the method for the synthetic aceticanhydride of above various liquid phase carbonyls, though some technology is very ripe and industrialization, generally all has following shortcoming: the selection of catalysts of the complicated and preparation of catalyst preparation process and activity is relatively poor and catalyst life is shorter; The methyl acetate conversion ratio is low, side reaction product is more, the methyl acetate space-time yield is lower so that bring difficulty for the subsequent separation process of product, and the process production cost is higher.
Summary of the invention
The object of the present invention is to provide methyl acetate and carbon monoxide liquid phase carbonyl to generate the preparation method and the method for preparing catalyst thereof of aceticanhydride (acetic anhydride), use catalyst provided by the invention can high conversion, high selectivity and high stability ground produces aceticanhydride.
The invention provides the technology and the process thereof of the synthetic aceticanhydride of a kind of methyl acetate and carbon monoxide liquid phase carbonyl, it is characterized in that reaction equation is:
CH
3COOCH
3+CO→(CH
3CO)
2O
The average conversion of this course of reaction methyl acetate is 58.0～78.0%, and aceticanhydride space-time average yield is 45.0～65.0mol/ (L.h).
Methyl acetate provided by the invention and carbon monoxide liquid phase carbonyl generate the method for preparing catalyst of aceticanhydride, comprise active component rhodium palladium complex A, cocatalyst component ethyl group iodine or methyl bromide B and carrier D, wherein the content of active component rhodium palladium complex A is 2.0～5.0% of catalyst weight, and the quality proportioning of rhodium and palladium is 4:1～5:1; The content of cocatalyst component ethyl group iodine or methyl bromide B is 0.5～9.5% of catalyst weight; Molecular sieve is ZSM series or MCM series among the carrier D, and its content is 30.0～40.0% of catalyst weight, and all the other components are one or more in kaolin and the silica.
Utilize infusion process that active component A and cocatalyst component B are supported in the solution of soluble metal element on the carrier D, accompany to burn at 500.0～600.0 ℃ of following high temperature to obtain catalyst in 1.0～1.5 hours.
The solution of described soluble metal element is the phosphate of acetate or acetum or containing metal potassium; Liquid phase solvent content is 70.0～80.0% of reaction system gross weight in the reaction system.
Utilize Preparation of Catalyst methyl acetate and carbon monoxide liquid phase carbonyl to generate the method for aceticanhydride, it is characterized in that: reaction temperature is 180.0～220.0 ℃, reaction pressure is 0.2～0.5MPa, and air speed is 2.5～4.8ml/g.h, and the carbon monoxide flow velocity is 800.0～1400.0ml/hr.
Co-catalyst ethyl group iodine that to use an advantage of the present invention be exactly this catalyst system or methyl bromide play good effect to the activity and the stability of catalyst activity component rhodium palladium complex, are convenient in the actual production process process operation parameter be adjusted and optimized.
Advantage of the present invention is exactly that methyl acetate and the carbon monoxide process of carrying out the synthetic aceticanhydride of liquid phase carbonyl has solved the oxidation of acetaldehyde co-production method and the ketene process flow process is complicated and the bigger problem of energy consumption, methyl acetate conversion ratio and aceticanhydride yield are higher in the course of reaction, and simple, the catalyst life of catalyst process of preparation is long, conversion ratio and selectivity height, for its industrial applications provides new approach.
Description of drawings
Fig. 1 is the change curve of methyl acetate conversion ratio and aceticanhydride space-time yield under the different catalysts reaction condition.
The specific embodiment
Below in conjunction with embodiment the present invention is further elaborated, but the present invention is not produced any restriction.
Example 1:
Adopt 500ml titanium pressing pressure reactor to carry out above working of an invention in the laboratory, the logistics composition and the operating parameter that add reactor are:
Methyl acetate addition: 1.20mol; The content of active component rhodium palladium complex A is 2.1%, and its proportioning is 4:1; Co-catalyst: ethyl group iodine or methyl bromide load on the ZSM-5 molecular sieve, and its percentage by weight is 2.5%; Carrier is the ZSM-5 molecular sieve, and its percentage by weight is 30.0%, and all the other components are kaolin and the aktivton of 1:1 for the quality proportioning; The weight ratio of catalyst and methyl acetate, carbon monoxide is 1:0.65:0.45; Acetic acid consumption: 0.22L; Carrier impregnation with accompany burning time: 65.0min, accompany that to burn temperature be 550.0 ℃; Reaction system is a liquor kalii acetici, and liquid phase solvent content is 70.0% of reaction system gross weight; Reaction time: 18.0min; Reaction temperature: 195.0 ± 1 ℃; Carbon monoxide pressure of tension: 0.39Ma; The carbon monoxide flow velocity is 1000.0ml/h; Hydrogen partial pressure: 0.3MPa; Methyl acetate conversion ratio: 62.0%; The aceticanhydride space-time yield is: 49.5mol/ (L.h).
Example 2:
Adopt 500ml titanium pressing pressure reactor to carry out above working of an invention in the laboratory, the logistics composition and the operating parameter that add reactor are:
Methyl acetate addition: 1.21mol; The content of active component rhodium palladium complex A is 2.1%, and its proportioning is 4.5:1; Cocatalyst B ethyl group iodine or methyl bromide load on the ZSM-5 molecular sieve, and its percentage by weight is 2.6%; Carrier is the ZSM-5 molecular sieve, and its percentage by weight is 35.0%, and all the other components are kaolin and the aktivton of 1:1.2 for the quality proportioning; The weight ratio of catalyst and methyl acetate, carbon monoxide is 1:0.68:0.45; Acetic acid consumption: 0.21L; Carrier impregnation with accompany burning time: 60.0min, accompany that to burn temperature be 560.0 ℃; Reaction system is a liquor kalii acetici, and liquid phase solvent content is 75.0% of reaction system gross weight; Reaction time: 20.0min; Reaction temperature: 198.0 ± 1 ℃; Carbon monoxide pressure of tension: 0.40Ma; The carbon monoxide flow velocity is 900.0ml/h; Hydrogen partial pressure: 0.3MPa; Methyl acetate conversion ratio: 59.2%; The aceticanhydride space-time yield is: 47.1mol/ (L.h).
Example 3:
Adopt 500ml titanium pressing pressure reactor to carry out above working of an invention in the laboratory, the logistics composition and the operating parameter that add reactor are:
Methyl acetate addition: 1.22mol; The content of active component rhodium palladium complex A is 2.1%, and its proportioning is 4.4:1; Cocatalyst B ethyl group iodine or methyl bromide load on the ZSM-5 molecular sieve, and its percentage by weight is 2.6%; Carrier is the ZSM-5 molecular sieve, and its percentage by weight is 34.9%, and all the other components are kaolin and the aktivton of 1:1.2 for the quality proportioning; The weight ratio of catalyst and methyl acetate, carbon monoxide is 1:0.68:0.45; Acetic acid consumption: 0.21L; Carrier impregnation with accompany burning time: 58.0min, accompany that to burn temperature be 550.0 ℃; Reaction system is a liquor kalii acetici, and liquid phase solvent content is 75.0% of reaction system gross weight; Reaction time: 20.0min; Reaction temperature: 200.0 ± 1 ℃; Carbon monoxide pressure of tension: 0.41Ma; The carbon monoxide flow velocity is 1200.0ml/h; Hydrogen partial pressure: 0.3MPa; Methyl acetate conversion ratio: 48.5%; The aceticanhydride space-time yield is: 42.3mol/ (L.h).
Example 4:
Adopt 500ml titanium pressing pressure reactor to carry out above working of an invention in the laboratory, the logistics composition and the operating parameter that add reactor are:
Methyl acetate addition: 1.20mol; The content of active component rhodium palladium complex A is 2.2%, and its proportioning is 4:1; Cocatalyst B ethyl group iodine or methyl bromide load on the MCM-41 molecular sieve, and its percentage by weight is 4.5%; Carrier is the MCM-41 molecular sieve, and its percentage by weight is 35.0%, and all the other components are kaolin and the aktivton of 1:3 for the quality proportioning; The weight ratio of catalyst and methyl acetate, carbon monoxide is 1:0.66:0.48; Acetic acid consumption: 0.20L; Carrier impregnation with accompany burning time: 60.0min, accompany that to burn temperature be 600.0 ℃; Reaction system is a liquor kalii acetici, and liquid phase solvent content is 80.0% of reaction system gross weight; Reaction time: 22.0min; Reaction temperature: 202.0 ± 1 ℃; Carbon monoxide pressure of tension: 0.41Ma; The carbon monoxide flow velocity is 1100.0ml/h; Hydrogen partial pressure: 0.3MPa; Methyl acetate conversion ratio: 67.1%; The aceticanhydride space-time yield is: 62.4mol/ (L.h).
Example 5:
Adopt 1000ml titanium pressing pressure reactor to carry out above working of an invention in the laboratory, the logistics composition and the operating parameter that add reactor are:
Methyl acetate addition: 2.4mol; The content of active component rhodium palladium complex A is 2.4%, and its proportioning is 4.5:1; Cocatalyst B ethyl group iodine or methyl bromide load on the MCM-41 molecular sieve, and its percentage by weight is 3.5%; Carrier is the MCM-41 molecular sieve, and its percentage by weight is 36.0%, and all the other components are kaolin; The weight ratio of catalyst and methyl acetate, carbon monoxide is 1:0.66:0.48; Acetic acid consumption: 0.42L; Carrier impregnation with accompany burning time: 75.0min, accompany that to burn temperature be 600.0 ℃; Reaction system is a liquor kalii acetici, and liquid phase solvent content is 75.0% of reaction system gross weight; Reaction time: 30.0min; Reaction temperature: 210.0 ± 1 ℃; Carbon monoxide pressure of tension: 0.40Ma; The carbon monoxide flow velocity is 1000.0ml/h; Hydrogen partial pressure: 0.3MPa; Methyl acetate conversion ratio: 59.8%; The aceticanhydride space-time yield is: 53.2mol/ (L.h).
Example 6:
Adopt 1000ml titanium pressing pressure reactor to carry out above working of an invention in the laboratory, the logistics composition and the operating parameter that add reactor are:
Methyl acetate addition: 2.44mol; The content of active component rhodium palladium complex A is 2.2%, and its proportioning is 4.8:1; Cocatalyst B ethyl group iodine or methyl bromide load on the ZSM-5 molecular sieve, and its percentage by weight is 2.5%; Carrier is the ZSM-5 molecular sieve, and its percentage by weight is 35.0%, and all the other components are silica; The weight ratio of catalyst and methyl acetate, carbon monoxide is 1:0.64:0.48; Acetic acid consumption: 0.47L; Carrier impregnation with accompany burning time: 70.0min, accompany that to burn temperature be 600.0 ℃; Reaction system is a liquor kalii acetici, and liquid phase solvent content is 80.0% of reaction system gross weight; Reaction time: 32.0min; Reaction temperature: 204.0 ± 1 ℃; Carbon monoxide pressure of tension: 0.40Ma; The carbon monoxide flow velocity is 1150.0ml/h; Hydrogen partial pressure: 0.3MPa; Methyl acetate conversion ratio: 65.2%; The aceticanhydride space-time yield is: 57.2mol/ (L.h).
The content of the foregoing description is represented as can be known by Fig. 1, the methyl acetate conversion ratio under different condition and the change curve of aceticanhydride space-time yield, utilize methyl acetate of the present invention and carbon monoxide liquid phase carbonyl to generate the process of aceticanhydride (acetic anhydride) and the catalyst of employing preparation thereof, in the laboratory operating parameter under the different condition is experimentized as can be known, it is average 60.3% that the methyl acetate yield changes, aceticanhydride space-time yield average out to 51.95%.
Methyl acetate that the present invention proposes and carbon monoxide liquid phase carbonyl generate the preparation method and the method for preparing catalyst thereof of aceticanhydride.Be described by preferred embodiment, person skilled obviously can be in not breaking away from content of the present invention, spirit and scope to equipment as herein described and the preparation method changes or suitably change realize the technology of the present invention with combination.Special needs to be pointed out is, the replacement that all are similar and change apparent to those skilled in the artly, they are regarded as being included in spirit of the present invention, scope and the content.
Claims (3)
1. methyl acetate and carbon monoxide liquid phase carbonyl generate the method for preparing catalyst of aceticanhydride, this catalyst comprises active component rhodium palladium complex A, cocatalyst component ethyl group iodine or methyl bromide B and carrier D, the content that it is characterized in that active component rhodium palladium complex A is 2.0～5.0% of catalyst weight, and the quality proportioning of rhodium and palladium is 4:1～5:1; The content of cocatalyst component ethyl group iodine or methyl bromide B is 0.5～9.5% of catalyst weight; Molecular sieve is ZSM series or MCM series among the carrier D, and its content is 30.0～40.0% of catalyst weight, and all the other components are one or more in kaolin and the silica; Utilize infusion process that active component A and cocatalyst component ethyl group iodine or methyl bromide B are supported in the solution of soluble metal element on the carrier D, obtained catalyst in 1.0～1.5 hours 500.0～600.0 ℃ of following high-temperature roastings.
2. methyl acetate and carbon monoxide liquid phase carbonyl generate the method for aceticanhydride, this method adopts the catalyst of the described method preparation of claim 1, it is characterized in that: the reaction time is 20.0min～30.0min, reaction temperature is 180.0～220.0 ℃, reaction pressure is 0.2～0.5MPa, air speed is 2.5～4.8ml/g.h, and the carbon monoxide flow velocity is 800.0～1400.0ml/hr.
3. method as claimed in claim 2 is characterized in that: the weight ratio of described catalyst and methyl acetate, carbon monoxide is 1:0.6～0.75:0.4～0.55.
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| CNB2006101306486A CN100486701C (en) | 2006-12-28 | 2006-12-28 | Liquid phase reaction process of methyl acetate and CO to produce acetic anhydride and its catalyst preparing process |
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| CN100486701C true CN100486701C (en) | 2009-05-13 |
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| CN102266795B (en) * | 2011-06-15 | 2013-09-11 | 陕西煤业化工技术开发中心有限责任公司 | Catalyst used for low water acetic acid synthetic technology and preparation and application method thereof |
| CN102319587B (en) * | 2011-06-15 | 2013-08-28 | 陕西煤业化工技术开发中心有限责任公司 | Catalyst used in carbonylation synthesis of acetic anhydride coproduced with acetic acid and preparation and application methods thereof |
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