CN113754510B - Method for preparing 1,3-butadiene - Google Patents
Method for preparing 1,3-butadiene Download PDFInfo
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- CN113754510B CN113754510B CN202111169899.6A CN202111169899A CN113754510B CN 113754510 B CN113754510 B CN 113754510B CN 202111169899 A CN202111169899 A CN 202111169899A CN 113754510 B CN113754510 B CN 113754510B
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- butadiene
- valerolactone
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C1/00—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon
- C07C1/20—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon starting from organic compounds containing only oxygen atoms as heteroatoms
- C07C1/247—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon starting from organic compounds containing only oxygen atoms as heteroatoms by splitting of cyclic ethers
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2529/00—Catalysts comprising molecular sieves
- C07C2529/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites, pillared clays
- C07C2529/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
- C07C2529/40—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11
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- Y—GENERAL 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
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/584—Recycling of catalysts
Abstract
The invention relates to a method for preparing 1,3-butadiene. The method comprises the following steps: heating a reactor filled with a catalyst to 200-600 ℃, and feeding gamma-valerolactone raw material and carrier gas into the reactor under the pressure condition of 0.01-10MPa to prepare 1,3-butadiene; the catalyst is zeolite molecular sieve HZSM-5 catalyst. The process can be carried out under continuous reaction conditions, and is easy to operate and control; the reaction can be carried out under a lower pressure condition, and the yield of 1,3-butadiene can reach 68.9%.
Description
Technical Field
The invention relates to a method for preparing 1,3-butadiene by using gamma-valerolactone as a raw material and zeolite molecular sieves HZSM-5 with different silica-alumina ratios as catalysts under the reaction conditions of heating and continuous flow.
Background
Due to the increasing decrease of fossil resources, the utilization and development of renewable resources are imminent. Biomass, as a clean renewable organic carbon source in nature, is widely used due to its abundant and readily available resources. Among them, lignocellulose, which is the most abundant biomass resource, can be converted into high value-added chemicals such as levulinic acid, gamma valerolactone and the like through catalysis. Gamma valerolactone, an important biomass-based platform compound, can be obtained in a variety of ways and can be converted further to chemicals and fuels, such as hydrogenation to 1,4-pentanediol and 2-methyltetrahydrofuran; decarboxylation under the action of acidic catalyst to obtain C 4 Further subjecting the olefin to polymerization to obtain C 8+ Olefins (J Q Bond et al science 2010,327: 1110-1114.). Therefore, the gamma-valerolactone serving as a raw material is converted into high value-added chemicals, so that the gamma-valerolactone has important and wide application prospect.
1,3-butadiene is an important chemical basic raw material, and is mainly used for producing butadiene styrene rubber, nitrile rubber and other rubbers, ABS resin and the like. Currently most of 1,3-butadiene is derived from the naphtha cracking Process to produce ethylene, 1,3-butadiene is a by-product of the Process (D L Sun et al, fuel Process technol.2019,197: 106193.). With the progress of the U.S. shale gas revolution, large quantities of ethane were mined and used for cracking to ethylene, resulting in an insufficient supply of 1,3-butadiene and an increase in price. Therefore, a new 1,3-butadiene production process is needed to solve its supply problems.
At present, except for C obtained by cracking naphtha 4 The mixture is extracted to prepare 1,3-butadiene, and the process technology is used for preparing 1,3-butadiene by using n-butane, n-butene and ethanol as raw materials. The Ni/Zn/Ce composite oxide catalyst is prepared by a sol-gel method in Chenfeng autumn and the like (Chenfeng autumn and the like, authorization notice number: CN 111871419A.) and is used for catalyzing n-butane oxidation dehydrogenationThe selectivity for 1,3-butadiene, 1,3-butadiene was 16.6%. The dehydrogenation process of the n-butene includes two types of direct dehydrogenation and oxidative dehydrogenation, wherein the direct dehydrogenation process is a strong endothermic reaction, the catalyst is seriously deactivated, and most researches focus on the oxidative dehydrogenation process at present. Yan et al (B Yan et al chemistry select.2020,36 x Supported by ZnCl 2 Modified Al 2 O 3 Thus obtaining FeVGrO x /n％ZnCl 2 /Al 2 O 3 (n =1,3,5,7,10) catalyst in CO 2 The selectivity of 1,3-butadiene, 1,3-butadiene, is 49% by catalyzing dehydrogenation of n-butene under atmosphere. On the other hand, in O 2 The oxidative dehydrogenation reaction is carried out under the atmosphere, so that potential safety hazards exist. Although the process of preparing 1,3-butadiene from ethanol is widely studied, 1,3-butadiene has a low yield, many side reactions and severe catalyst deactivation problems (e.v. makshina et al. Chem.soc. Rev.2014, 43. On the other hand, although the preparation of butene from γ -valerolactone is reported (l.lin et al. Nat. Mater.2020,19, 86-93.), no report is currently made on the preparation of 1,3-butadiene from γ -valerolactone.
In recent research progress about 1,3-butadiene, no good production process is found for solving the supply problem of 1,3-butadiene, and most processes have the problems of low yield of 1,3-butadiene, more byproducts, easy inactivation of the catalyst and the like. Therefore, new production processes need to be explored to solve these problems and to increase the yield of 1,3-butadiene as much as possible.
Disclosure of Invention
The invention provides a method for preparing 1,3-butadiene by taking gamma-valerolactone as a raw material for the first time. The invention adopts reproducible gamma-valerolactone as raw material and zeolite molecular sieve HZSM-5 as catalyst to prepare 1,3-butadiene. The process can be carried out under continuous reaction conditions, and is easy to operate and control; the reaction can be carried out under a lower pressure condition, and the yield of 1,3-butadiene can reach 68.9%.
The invention is realized by adopting the following technical scheme:
a process for preparing 1,3-butadiene comprising the steps of:
heating a reactor filled with a catalyst to 200-600 ℃, and feeding gamma-valerolactone raw material and carrier gas into the reactor under the pressure condition of 0.01-10MPa to prepare 1,3-butadiene;
wherein the reactor is a fixed bed, a fluidized bed or a moving bed, and preferably a fixed bed reactor;
the raw material is pure gamma-valerolactone or a gamma-valerolactone solution, and when the raw material is a gamma-valerolactone aqueous solution, the preferred concentration is 40-60wt.%;
the mass space velocity of the gamma-valerolactone in the reaction is 0.1-100h -1 Preferably, the space velocity is 0.2-5h -1 ；
The catalyst is a zeolite molecular sieve HZSM-5 catalyst with different silica-alumina ratios, and the preferred silica-alumina ratio is 38-85;
the temperature of the reactor is preferably 350-450 ℃;
the carrier gas is nitrogen, helium or argon; preferably nitrogen;
the reaction pressure is preferably 0.1 to 1MPa.
The volume ratio of the corresponding carrier gas to the feeding amount of the raw material gamma-valerolactone is in the range of 30-300000, and preferably in the range of 300-12000.
The invention has the substantive characteristics that:
currently, 1,3-butadiene is produced primarily as a byproduct in the naphtha cracking to ethylene section. With the gradual decrease of fossil resources, the production and supply of 1,3-butadiene will be challenging in the future. The invention takes the biomass-based platform compound gamma-valerolactone as the raw material for the first time and prepares 1,3-butadiene through catalytic reaction. The process takes renewable resources as raw materials, takes green and environment-friendly heterogeneous catalysis as a technical means, and takes the prepared and applied mature zeolite molecular sieve HZSM-5 as a catalyst to prepare 1,3-butadiene. The process has mild reaction condition, simple operation and high selectivity and yield of 1,3-butadiene.
The invention has the advantages of
The invention firstly provides a method for preparing 1,3-butadiene by taking gamma-valerolactone as a raw material. The gamma-valerolactone is an important biomass-based platform compound, has wide sources and is easy to obtain. At present, no relevant process for preparing 1,3-butadiene by using gamma-valerolactone as a raw material is reported. The invention can use a fixed bed reactor, is a continuous reaction, has mild reaction conditions and is easy to operate and control; the reaction can be carried out under the condition of low pressure, and the carrier gas is nitrogen or other inert gases, so that the method is safer compared with a butylene oxidative dehydrogenation process; the catalyst for the reaction is zeolite molecular sieve HZSM-5 which is widely applied, and compared with iron-based and molybdenum-bismuth-based catalysts used in other processes, the catalyst is cheaper, and the preparation process is simple and mature; in the aspects of selectivity and yield of 1,3-butadiene, the selectivity and yield are higher than those in the traditional process, the selectivity of 1,3-butadiene in the invention is 70.6%, and the yield is 68.9%; therefore, the invention has great industrial application potential.
Detailed Description
In the method, under the action of a zeolite molecular sieve HZSM-5 catalyst, gamma-valerolactone is subjected to catalytic conversion to obtain 1,3-butadiene.
HZSM-5 catalysts with different silica-alumina ratios are filled in a fixed bed reactor provided with a quartz tube, the length of the fixed bed reactor is 40cm, and the inner diameter is 20mm. And raising the temperature of the catalyst bed layer to a set reaction temperature, wherein the catalyst bed layer accounts for 1-5cm of the height of the reaction tube. The raw material is pure gamma-valerolactone or gamma-valerolactone aqueous solution, and the concentration of the gamma-valerolactone aqueous solution is 20-80wt.%. The reaction solution is mixed with metered nitrogen gas according to a set flow rate through a high-pressure infusion pump and is sent into a fixed bed reactor, and the gasified reaction solution is contacted with a catalyst filled in the fixed bed reactor to react. The reaction product was collected in a collection bottle and the product was condensed using an ice-water mixture. The product is collected once per hour, the liquid product obtained after condensation is analyzed through gas chromatography, and the gas product is analyzed through on-line real-time monitoring gas chromatography, so that the conversion rate of gamma-valerolactone and the selectivity of each product are calculated.
The present invention is further illustrated by the following examples, but the present invention is not limited to these specific examples.
Catalytic conversion of gamma valerolactone to 1,3-butadiene example:
example 1
0.75g of HZSM-5 catalyst with a silica-alumina ratio of 21 is filled in a fixed bed reactor with the inner diameter of 20 mm; the reaction is heated by an electric furnace outside the reactor, the temperature is measured by a thermocouple in a catalyst bed layer of the reactor, the reaction temperature is controlled at 400 ℃, the reaction raw material is pure gamma-valerolactone, the pure gamma-valerolactone enters the reactor through a high-pressure infusion pump according to the set feeding amount of 1.02ml/h, and the mass space velocity of the pure gamma-valerolactone is 1.44h -1 (ii) a The carrier gas is nitrogen, and the flow rate of the nitrogen is 30cm 3 Min (the volume ratio of carrier gas to gamma-valerolactone is 1765), feeding reaction raw materials gamma-valerolactone and nitrogen into a reactor; the reaction pressure is 0.1MPa; and (2) condensing the liquid reaction product, then feeding the condensed liquid reaction product into a collecting bottle for gas chromatographic analysis, feeding the gas product into an online real-time monitoring gas chromatograph for analysis, collecting the gas product once per hour, wherein the reaction time is 5 hours, and respectively calculating the conversion rate of gamma-valerolactone and the selectivity of 1,3-butadiene per hour. The results are shown in Table I, which is an average of 5 hour reactions. Under the reaction conditions, the conversion of gamma valerolactone was 87.3%, the selectivity of 1,3-butadiene was 44.2%, and the yield was 38.6%.
Examples 2 to 7
The reaction for the catalytic conversion of gamma valerolactone to produce 1,3-butadiene was carried out in the same experimental procedure as in example 1, except that the kind of the catalyst was changed. HZSM-5 catalysts with silica to alumina ratios of 38, 50, 60, 70, 85, 200 correspond to examples 2-7, respectively. The results are shown in Table one, where the conversion of gamma valerolactone, the selectivity of 1,3-butadiene and the yield of 1,3-butadiene are average values over 5 hours.
Watch 1
Through experiments, the conversion rate of gamma-valerolactone is gradually increased along with the increase of the silicon-aluminum ratio. The silica-alumina ratio is in the range of 38-85, the selectivity of 1,3-butadiene is higher, and can reach 41-49%. Too high or too low a silica to alumina ratio is not favorable for producing 1,3-butadiene. Therefore, the HZSM-5 catalyst with the silica-alumina ratio of 38-85 has better effect and can be better used for catalyzing gamma-valerolactone to prepare 1,3-butadiene.
Examples 8 to 11
The reaction for the catalytic conversion of gamma valerolactone to 1,3-butadiene was carried out in the same experimental procedure as in example 3, except that pure gamma valerolactone was changed to gamma valerolactone aqueous solutions of different concentrations. Aqueous solutions of gamma valerolactone at concentrations of 20, 40, 60, 80wt.% correspond to examples 8-11, respectively. The results are shown in Table II, where the conversion of gamma valerolactone, the selectivity of 1,3-butadiene and the yield of 1,3-butadiene were averaged over 5 hours.
Watch two
Experimental results show that the conversion rate of gamma-valerolactone can be improved by adding water, and when the concentration of the gamma-valerolactone is 60wt.%, the conversion rate of the gamma-valerolactone is improved to 91.8%, and the selectivity of 1,3-butadiene is also greatly improved to 66.7%. At a concentration of 80wt.% gamma valerolactone, the conversion of gamma valerolactone was 76.7% and the selectivity of 1,3-butadiene was 49.8%. At concentrations of 20 and 40wt.% gamma valerolactone, the conversion was higher, but the by-products contained more ethylene and propylene, with a lower selectivity for 1,3-butadiene. Thus, an aqueous gamma valerolactone solution concentration of 40 to 60wt.% is more favorable for the production of 1,3-butadiene.
Examples 12 to 13
The reaction for the catalytic conversion of gamma valerolactone to produce 1,3-butadiene was carried out in the same experimental procedure as in example 10, except that the mass space velocity was changed. The mass space velocity is 0.6 and 0.4h -1 Corresponding to examples 12 and 13, respectively. The results are shown in Table three, where the conversion of gamma valerolactone, the selectivity of 1,3-butadiene and the yield of 1,3-butadiene are average values over 5 hours.
Watch III
The experimental result shows that the mass space velocity is reduced, the conversion rate of gamma-valerolactone and the selectivity of 1,3-butadiene can be improved, and the mass space velocity is 0.6h -1 In the process, the conversion rate of gamma-valerolactone is improved to 93.5 percent, and the selectivity of 1,3-butadiene is 67.5 percent; the mass space velocity is 0.4h -1 In the process, the conversion rate of gamma-valerolactone reaches 97.6 percent, the selectivity of 1,3-butadiene is 70.6 percent, and the yield reaches 68.9 percent.
Examples 14 to 17
The reaction for the catalytic conversion of gamma valerolactone to produce 1,3-butadiene was carried out in the same experimental procedure as in example 10, except that the reaction temperature was changed. The reaction temperatures were 250, 350, 450 and 550 ℃ for examples 14 to 17, respectively. The results are shown in Table four, where the conversion of gamma valerolactone, the selectivity of 1,3-butadiene and the yield of 1,3-butadiene are average values over 5 hours.
Watch four
The experimental result shows that the conversion rate of gamma-valerolactone is gradually increased with the increase of the temperature, but the selectivity of 1,3-butadiene is gradually reduced, the byproducts are increased, the gamma-valerolactone can be well converted into 1,3-butadiene within the range of 350-450 ℃, the conversion rate of the gamma-valerolactone is 97.9% and the selectivity of 1,3-butadiene is 65.1% at the temperature of 450 ℃. When the temperature was lowered to 250 ℃, the conversion of gamma valerolactone was low and the selectivity of 1,3-butadiene was only 6.4%. At 550 deg.c, the conversion of gamma-valerolactone reaches 100%, but the selectivity of 1,3-butadiene is only 5%, ethylene and propylene are the main products. Therefore, the temperature of 350-450 ℃ is the more suitable reaction temperature for preparing 1,3-butadiene by the catalytic conversion of gamma-valerolactone.
The embodiments show that the zeolite HZSM-5 is used for catalyzing gamma-valerolactone to efficiently prepare 1,3-butadiene, the process is simple, the reaction raw materials can be obtained from renewable resources, and the HZSM-5 catalyst is mature and cheap and easy to obtain. The invention uses a fixed bed reactor, continuously reacts under the condition of low pressure, has low requirement on equipment and simple product separation process, and therefore, the invention has good application prospect.
The invention is not the best known technology.
Claims (7)
1. A process for preparing 1,3-butadiene, characterized in that the process comprises the steps of:
heating a reactor filled with a catalyst to 200-600 ℃, and feeding gamma-valerolactone raw material and carrier gas into the reactor under the pressure condition of 0.01-10MPa to prepare 1,3-butadiene;
wherein the reactor is a fixed bed, a fluidized bed or a moving bed;
the raw material is pure gamma-valerolactone or a gamma-valerolactone solution, and when the raw material is a gamma-valerolactone aqueous solution, the concentration is 40-60wt.%;
the mass space velocity of the gamma-valerolactone in the reaction is 0.1-100h -1 ；
The catalyst is a zeolite molecular sieve HZSM-5 catalyst;
the carrier gas is nitrogen, helium or argon.
2. The process of claim 1 for making 1,3-butadiene wherein the reactor temperature is 350 to 450 ℃.
3. The process of claim 1 for making 1,3-butadiene wherein the reaction pressure is 0.1 to 1MPa.
4. The process of claim 1 for producing 1,3-butadiene wherein the ratio of the volume of the carrier gas to the feed of gamma valerolactone is in the range of 30 to 300000.
5. The process of claim 1 for producing 1,3-butadiene in which the ratio of the volume of the carrier gas to the feed of gamma valerolactone is in the range of 300 to 12000.
6. The process of claim 1 for preparing 1,3-butadiene wherein the zeolite molecular sieve HZSM-5 catalyst has a silica to alumina ratio of 38 to 85.
7. The process of claim 1 for preparing 1,3-butadiene wherein the mass space velocity of gamma valerolactone in the reaction is from 0.2 to 5 hours -1 。
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1668556A (en) * | 2002-07-12 | 2005-09-14 | 巴斯福股份公司 | Method for the production of butadiene from n-butane |
| WO2013147708A2 (en) * | 2012-03-28 | 2013-10-03 | Agency For Science, Technology And Research | A process to produce a diene from a lactone |
| CN110997878A (en) * | 2017-07-18 | 2020-04-10 | 鲁姆斯科技有限责任公司 | Integrated thermal cracking and hydrogenation process for olefin production |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1668556A (en) * | 2002-07-12 | 2005-09-14 | 巴斯福股份公司 | Method for the production of butadiene from n-butane |
| WO2013147708A2 (en) * | 2012-03-28 | 2013-10-03 | Agency For Science, Technology And Research | A process to produce a diene from a lactone |
| CN110997878A (en) * | 2017-07-18 | 2020-04-10 | 鲁姆斯科技有限责任公司 | Integrated thermal cracking and hydrogenation process for olefin production |
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