阅读说明：本技术 一种采用固体酸催化合成乙酰正丙醇的方法 (Method for synthesizing acetyl-n-propanol by adopting solid acid catalysis ) 是由 曹华鹏 宋伟 陈昞志 王长锦 张正邦 李子剑 于 2021-08-17 设计创作，主要内容包括：本发明涉及采用固体酸催化合成乙酰正丙醇的方法,是以固体酸替代盐酸溶液反应,相应改变了反应温度和投料配比等工艺参数,所采用的固体酸包括不同规格的沸石分子筛催化剂、阳离子树脂催化剂,所述的沸石分子筛催化剂,包括HY型、Hβ型、HZSM型。不仅解决了因为废水中残留无机酸需要加入碱来中和,进而带来的废水处置问题,而且由于固体酸酸性的调节,减少了聚合杂质的产生,提升了产品的含量,以及提高了产品的收率。产品得率高达89～91%,纯度94～96%。(The invention relates to a method for synthesizing acetyl-n-propanol by using solid acid as a catalyst, which is characterized in that the solid acid is used for replacing a hydrochloric acid solution for reaction, the reaction temperature, the feeding ratio and other process parameters are correspondingly changed, the adopted solid acid comprises zeolite molecular sieve catalysts and cationic resin catalysts with different specifications, and the zeolite molecular sieve catalysts comprise HY type, H beta type and HZSM type. The method not only solves the problem of wastewater treatment caused by the fact that alkali is required to be added for neutralization of residual inorganic acid in the wastewater, but also reduces the generation of polymerization impurities, improves the content of products and improves the yield of the products due to the adjustment of the acidity of the solid acid. The product yield is up to 89-91%, and the purity is 94-96%.)

1. A method for synthesizing acetyl-n-propanol by using solid acid catalysis has the following reaction formula:

solid acid is used to replace hydrochloric acid solution for reaction, and the reaction temperature and the feeding ratio are correspondingly changed.

2. The method for synthesizing acetyl-n-propanol by using the solid acid catalyst as claimed in claim 1, wherein the solid acid used comprises zeolite molecular sieve catalyst and cationic resin catalyst with different specifications.

3. The method for synthesizing acetyl n-propanol by using solid acid as catalyst in claim 2, wherein the zeolite molecular sieve catalyst includes HY type, H β type and HZSM type.

4. The method for synthesizing n-propanol including acetyl chloride using solid acid as catalyst in claim 3, wherein the zeolite molecular sieve is HZSM-5.

5. The method for synthesizing acetyl-n-propanol by using solid acid catalysis as claimed in claim 1, which is characterized by comprising the following specific processes:

3000ml of a hydrogenation reaction kettle is filled with 1000g of 2-methylfuran, 5g of palladium carbon catalyst and 250g of water, and 5g of solid acid catalyst is added;

after 3 times of nitrogen-hydrogen replacement, controlling the pressure in the reaction kettle to be 0.10-1.00 MPa, controlling the reaction temperature to be 5-60 ℃ and the reaction time to be 10-20 hours;

after the reaction is finished, filtering the reaction solution by a filter, and directly distilling the filtrate under reduced pressure to obtain a product; adding 100g of 2-methylfuran into the catalyst intercepted in the filter, backwashing into the hydrogenation kettle, and directly using the catalyst in the next kettle for reaction;

when the next kettle is used, 0.1-0.5 g of palladium carbon catalyst and 1% of solid acid catalyst of the initial feeding are added.

Technical Field

The invention relates to a synthesis method of acetyl-n-propanol, belonging to the field of chemical synthesis.

Background

Acetyl-n-propanol (English name: 3-acetyl-1-propanol, also known as 1-pentanol-4-one, gamma-acetyl-n-propanol, gamma-acetyl propanol) is an important medical intermediate, is mainly used for antimalarial chloroquine phosphate, and can also be used for producing vitamin B1 and the like. It volatilizes in steam, cyclizes when distilled under atmospheric pressure, reacts with aluminum trioxide to produce levulinic acid, and is electrolytically reduced to produce pentanol. Low toxicity, and chronic poisoning caused by long-term contact with volatilized gas, and stimulation of central nervous system. Concentrated solutions can cause liver and kidney disorders. The caliber MLD of the rat is 4180 mg/kg.

The preparation method of gamma-acetyl-n-propanol reported in the prior art comprises the following steps: 2-methylfuran or acetylbutyrolactone is used as a starting material, and gamma-acetyl-n-propanol is prepared by catalytic hydrogenation separation under an acidic condition. For example, chinese patent CN102140058A discloses a method for preparing gamma-acetyl-n-propanol from 2-methylfuran in the presence of concentrated hydrochloric acid and Pd/C catalyst. The literature (Synthetic communications, 2000,30,2295-2299) reports the synthesis of gamma-acetyl-n-propanol from acetylbutyrolactone by hydrolysis with hydrochloric acid. In the processes, the raw materials are high in price, hydrochloric acid is adopted, post-treatment is complicated, the problems of high production cost, high environmental protection pressure and the like of the gamma-acetyl-n-propanol are caused, and the gamma-acetyl-propanol is low in yield and poor in selectivity. The chinese patent CN201811224270.5, filed by the applicant at 2018.10.19, discloses a catalyst for preparing gamma-acetyl propanol, which comprises a main catalyst and a cocatalyst, wherein the active component of the cocatalyst comprises one or more of group viii metal elements, and the active component of the cocatalyst is selected from platinum and rhodium. In the presence of catalyst, acid water solution and hydrogen, 2-methylfuran reacts at 5-30 deg.c and 0.1-0.3MPa to produce gamma-acetyl propanol. The acidic aqueous solution is an aqueous solution containing hydrochloric acid, and the mass concentration of the hydrochloric acid is 0.1-0.3%. After the cocatalyst is added, the catalyst selectivity is improved, side reactions and other impurities are less, and the product content and yield are high. However, the residual inorganic acid in the wastewater generated by the reaction needs to be neutralized by adding alkali, thereby bringing about the problem of wastewater disposal.

The research on solid acid catalysts by Dexin et al (Guangdong chemical industry, 5 th 2012, P286) summarizes the types of solid acids currently in use: (1) immobilized liquid acid, (2) oxide, (3) sulfide, (4) metal salt, (5) zeolite molecular sieve, (6) heteropolyacid, (7) cation exchange resin, (8) natural clay mineral and (9) solid super acid. "ZSM-5 molecular sieve synthesis research progress" in research analysis (6 months 2020), i.e., Yang trade, describes that ZSM zeolite molecular sieve has special properties and is widely applied in petrochemical industries, such as catalytic cracking, toluene disproportionation, etc., environmental protection, pharmaceutical intermediates, fine chemical industries, etc. The research work of green synthesis of the molecular sieve is reviewed from the aspects of a hydrothermal method, an ionothermal method, a dry gel method, a solvent-free method and the like. The characteristics of the molecular sieve catalyst and several molecular sieves, such as the fine oxidation desulfurization of the modified Ag/TS molecular sieve catalyst, are analyzed in the text of the research progress of the molecular sieve catalyst (building engineering technology and design, 2015, 12 months). The combined temperature programming and roasting method can reduce the shedding of the heteroatoms of the aluminum phosphate molecular sieve, improves the thermal stability and is beneficial to catalyzing the DBT oxidation desulfurization reaction, but the catalyst is easy, and the improvement of the stability is a hotspot of research. The application of the ZSM-5 molecular sieve catalyst in desulfurization mainly comprises pyrolysis desulfurization, o-hydrogen desulfurization and hydrodesulfurization, and the main objects are mercaptan, thioether and thiophene micromolecule sulfide. It is also pointed out that the ZSM-5 molecular sieve catalyst can only be used for the oxidation removal of small molecular sulfides because the pore channels are crossed and the pore diameter is smaller. The effective aperture of the ZSM-5 is improved by adopting a proper method, the range of objects to be removed can be enlarged, and the desulfurization rate of oil products is improved. The applicant discloses a method for continuously preparing 4,4 '-diaminodiphenylmethane derivatives by solid acid catalysis in a Chinese patent application No. 2015108693417 (2016.2), wherein aniline derivatives and formaldehyde are used as raw materials, and condensation reaction is carried out by solid acid catalysis in a first-stage or second-stage fixed bed reactor, wherein the liquid space velocity of the reaction is 2-9h < -1 > to obtain the 4, 4' -diaminodiphenylmethane derivatives (MDA, MDT and MOCA). The invention uses solid acid H beta, HY and HZSM-5 molecular sieves to replace traditional inorganic acid catalysts such as hydrochloric acid and sulfuric acid, and continuously reacts. Solves the problems of low yield caused by insufficient conversion of intermediates or low yield caused by more side reactions in the prior preparation of diphenylmethane by using solid acid to catalyze aniline and formaldehyde for condensation. However, no report about the synthesis of acetyl-n-propanol catalyzed by solid acid is available at present.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides a method for synthesizing acetyl-n-propanol, which adopts solid acid to replace hydrochloric acid for synthesizing the acetyl-n-propanol, thereby not only solving the problem of wastewater treatment caused by the fact that inorganic acid remained in wastewater needs to be neutralized by adding alkali, but also reducing the generation of polymerization impurities, improving the content of products and improving the yield of the products because the solid acid is adjusted in an acidic manner.

In order to solve the technical problem, the invention is realized as follows:

a synthesis method of acetyl-n-propanol comprises the following reaction formula:

solid acid is used for replacing hydrochloric acid solution for reaction, and the adopted solid acid comprises zeolite molecular sieve catalysts with different specifications, cation resin catalysts and the like, wherein the zeolite molecular sieve catalysts are preferably selected and comprise HY type, H beta type, HZSM type and the like.

Preferably, the solid acid is preferably HZSM-5 molecular sieve because higher product yield and product content can be obtained than other solid acids.

Zeolitic molecular sieves are hydrates of crystalline aluminosilicates with uniform micropores. The chemical general formula is as follows: mx/m [ (AlO2) x. (SiO2) y ]. zH 2O. M represents cation, M represents valence number, z represents hydration number, x and y are integers, the pore size of the integer is equivalent to the size of a common molecule, molecules with smaller pore size are adsorbed into a cavity, molecules with larger pore size are excluded from the cavity, and the molecular sieve plays a role in sieving molecules, so the molecular sieve is named.

The side reaction of the previous polymerization under the catalysis of hydrochloric acid is as follows, and the generation of polymerization impurities is reduced after the reaction is catalyzed by solid acid.

A method for synthesizing acetyl-n-propanol comprises the following specific processes:

1.3000ml hydrogenation reaction kettle is put with 1000g 2-methyl furan, 5g palladium carbon catalyst and 250g water, and 5g solid acid catalyst is added;

2. after 3 times of nitrogen-hydrogen replacement, controlling the pressure in the reaction kettle to be 0.10-1.00 MPa, controlling the reaction temperature to be 5-60 ℃ and the reaction time to be 10-20 hours;

3. after the reaction is finished, filtering the reaction solution by a filter, and directly distilling the filtrate under reduced pressure to obtain a product; adding 100g of 2-methylfuran into the catalyst intercepted in the filter, backwashing into the hydrogenation kettle, and directly using the catalyst in the next kettle for reaction;

4. when the next kettle is used, 0.1-0.5 g of palladium carbon catalyst and 0.05g of solid acid catalyst (1% of the initial charge) are added.

Has the advantages that: the method adopts the solid acid (H-Y, H-beta, ZSM and other molecular sieves) to replace hydrochloric acid for synthesizing the acetyl-n-propanol, thereby not only solving the problem of wastewater treatment caused by the fact that inorganic acid remained in the wastewater needs to be neutralized by adding alkali, but also reducing the generation of polymerization impurities, improving the content of products and improving the yield of the products because the solid acid is adjusted in an acidic way. The product yield is up to 89-91%, and the purity is 94-96%.

Detailed Description

The present invention will be described in further detail with reference to specific embodiments.

A method for synthesizing acetyl-n-propanol comprises the following steps:

1.3000ml hydrogenation reaction kettle is put with 1000g 2-methyl furan, 5g palladium carbon catalyst and 250g water, and 5g solid acid catalyst is added;

2. after 3 times of nitrogen-hydrogen replacement, controlling the pressure in the reaction kettle to be 0.10-1.00 MPa, controlling the reaction temperature to be 5-60 ℃ and the reaction time to be 10-20 hours;

3. after the reaction is finished, filtering the reaction solution by a carbon rod filter, and directly distilling the filtrate to obtain a product; adding 100g of 2-methylfuran into the catalyst intercepted in the filter, backwashing into the hydrogenation kettle, and directly using the catalyst in the next kettle for reaction;

4. when the next kettle is used, 0.1-0.5 g of palladium carbon catalyst and 0.05g of solid acid catalyst (1% of the initial charge) are added.

The results of examples 1 to 5 using different catalysts are shown in table 1, and it can be seen that solid acid (H-Y, H-beta, ZSM and other molecular sieves) is used for synthesizing acetyl-n-propanol instead of hydrochloric acid, so that the content of the product is increased, and the yield of the product is increased.

TABLE 1

Serial number	Kind of catalyst	Solid acid dosage per gram	Product yield/%	Content of product/%)
					1	Hydrochloric acid	25g	80％	90％
2	HY-7.5	5g	85％	92％
					3	Hβ-100	5g	83％	90％
4	Hβ-40	5g	87％	93％
					5	HZSM-5	5g	90％	95％

Example 6 the amount of HZSM-5 was examined and the results are shown in table 2, which shows that the product yield and quality are stable and no significant change occurs as the solid acid HZSM-5 is continuously added.

TABLE 2

Serial number	Solid acid dosage (supplementary amount)/g	Product yield/%	Content of product/%)	Remarks for note
					1	5g	90％	95％	First kettle
2	0.05g	89％	96％	Apply it for 1 time
					3	0.05g	90％	96％	Apply it for 2 times
4	0.05g	91％	94％	Apply it 3 times

The method adopts the solid acid to replace hydrochloric acid for synthesizing the acetyl-n-propanol, correspondingly adjusts process parameters such as reaction temperature and the like, not only solves the problem of wastewater treatment caused by the fact that inorganic acid remained in the wastewater needs to be neutralized by adding alkali, but also reduces the generation of polymerization impurities and improves the content of products because the solid acid is adjusted in an acidic way.

The above embodiments do not limit the technical solutions of the present invention in any way, and all technical solutions obtained by means of equivalent replacement or equivalent transformation fall within the protection scope of the present invention.