Preparation method of isononanoic acid
阅读说明：本技术 一种异壬酸的制备方法 (Preparation method of isononanoic acid ) 是由 李俊 韩玉婵 付晓静 陈睿 于 2021-01-21 设计创作，主要内容包括：本发明涉及一种异壬酸的制备方法,其特征在于,以磺化介孔硅-碳复合材料为催化剂,过氧化氢为氧化剂,将异壬醛氧化为异壬酸。与现有技术相比,本发明具有反应条件温和、副产物少、产品纯度高、收率高和经济效益好等特点,对环境造成污染小,符合绿色发展理念。(The invention relates to a preparation method of isononanoic acid, which is characterized in that isononanoic aldehyde is oxidized into isononanoic acid by taking sulfonated mesoporous silicon-carbon composite material as a catalyst and hydrogen peroxide as an oxidant. Compared with the prior art, the method has the characteristics of mild reaction conditions, few byproducts, high product purity, high yield, good economic benefit and the like, causes little pollution to the environment, and accords with the green development concept.)
1. The preparation method of isononanoic acid is characterized in that isononanoic aldehyde is oxidized into isononanoic acid by taking sulfonated mesoporous silicon-carbon composite material as a catalyst and hydrogen peroxide as an oxidant.
2. The method for producing isononanoic acid according to claim 1, specifically comprising the steps of:
(1) mixing isononanal, acetonitrile, hydrogen peroxide and a sulfonated mesoporous silicon-carbon composite material, heating and reacting;
(2) after the reaction is finished, cooling the reaction mixture to room temperature;
(3) evaporating acetonitrile in the reaction mixture, adjusting the reaction mixture to be alkaline by using a sodium hydroxide solution, and extracting by using an organic solvent;
(4) acidifying the water phase obtained by extraction with hydrochloric acid, and extracting with an organic solvent;
(5) the organic phase from the extraction was collected and evaporated to give nonanoic acid.
3. The method for preparing isononanoic acid according to claim 2, wherein the reaction temperature in the step (1) is 40 to 80 ℃, and the reaction time is 1.5 to 2.5 hours;
the concentration of the sodium hydroxide solution in the step (3) is 1.8-2.2 mol/L, and the pH of the reaction mixture is adjusted to 7.5-8.5;
the concentration of hydrochloric acid in the step (4) is 5.5-6.5 mol/L, and the pH value of the water phase is adjusted to 1.8-2.2;
the organic solvent used for extraction includes ethyl acetate.
4. The method for preparing isononanoic acid according to claim 1, wherein the hydrogen peroxide concentration is 25-35 wt%, and the molar ratio of the sulfonated mesoporous silicon-carbon composite material to the hydrogen peroxide to isononanoic aldehyde is 0.04-0.16: 1-6: 1.
5. The method for preparing isononanoic acid according to claim 1, wherein the sulfonated mesoporous silicon-carbon composite material is prepared by the following steps:
(1) preparing mesoporous silicon by adopting a sol-gel method;
(2) adding concentrated sulfuric acid into the mesoporous silicon;
(3) loading sucrose on the mesoporous silicon treated by concentrated sulfuric acid in the step (2) by adopting a chemical dipping method;
(4) carrying out carbonization treatment on the sucrose-loaded mesoporous silicon to obtain a mesoporous silicon-carbon composite material;
(5) carrying out hydrothermal sulfonation treatment on the mesoporous silicon-carbon composite material to obtain the sulfonated mesoporous silicon-carbon composite material.
6. The method for preparing isononanoic acid according to claim 5, wherein the sol-gel process of step (1) is specifically:
the first step is as follows: adding dodecylamine into a mixed solution of deionized water, hydrochloric acid and ethanol, and uniformly mixing to prepare a solution A;
the second step is that: uniformly mixing isopropanol and tetraethoxysilane to prepare a solution B;
the third step: slowly dripping the solution B into the solution A under strong stirring;
the fourth step: crystallizing, filtering, washing, drying, grinding and roasting to obtain the mesoporous silicon.
7. The method for preparing isononanoic acid according to claim 6, wherein the molar ratio of the deionized water, the hydrochloric acid, the ethanol and the dodecylamine in the first step is 120-130: 0.06-0.08: 20-24: 1;
the volume ratio of the isopropanol to the ethyl orthosilicate in the second step is 0.3-0.4: 1;
and in the third step, the volume ratio of the solution A to the solution B is 3-4: 1.
8. The method for preparing isononanoic acid according to claim 5, wherein the process of adding the mesoporous silicon by the concentrated sulfuric acid in the step (2) is specifically as follows: ultrasonically oscillating the mesoporous silicon prepared in the step (1) in water, adding 98% concentrated sulfuric acid, and continuing to ultrasonically oscillate;
the sucrose loading method in the step (3) specifically comprises the following steps: adding sucrose into the mixture of concentrated sulfuric acid and mesoporous silicon obtained in the step (2), stirring to completely dissolve the sucrose, soaking for a period of time at constant temperature, and then drying and grinding the mixture;
the carbonization treatment process in the step (4) is specifically as follows: and (4) carrying out primary carbonization on the ground product obtained in the step (3), and then carrying out high-temperature carbonization under the protection of inert gas to obtain the mesoporous silicon-carbon composite material.
9. The method for preparing isononanoic acid according to claim 8, wherein the molar ratio of concentrated sulfuric acid, water and mesoporous silicon in step (2) is 0.1-0.2: 6-8: 1; the mol ratio of the sucrose to the mesoporous silicon in the step (3) is 1.2-1.4: 1, the constant-temperature dipping temperature is 35-45 ℃, the dipping time is 8-12 hours, the drying temperature is 90-110 ℃, the drying time is 5-6 hours, and the grinding granularity is 200-800 meshes; and (4) performing primary carbonization at the temperature of 150-170 ℃ for 5-7 h, performing high-temperature carbonization at the temperature of 750-850 ℃ for 5-7 h.
10. The method for preparing isononanoic acid according to claim 5, wherein the hydrothermal sulfonation treatment in step (5) is specifically: adding concentrated sulfuric acid into the mesoporous silicon-carbon composite material obtained in the step (4) under the protection of inert gas, heating and refluxing, cooling to room temperature after the reaction is finished, diluting, filtering, washing the reaction solution to obtain a concentrated sulfuric acid-treated mesoporous silicon-carbon composite material, then transferring the concentrated sulfuric acid-treated mesoporous silicon-carbon composite material into a hydrothermal reaction kettle, carrying out hydrothermal reaction for a period of time, washing the product to be neutral, and drying to obtain the sulfonated mesoporous silicon-carbon composite material.
Technical Field
The invention relates to the technical field of heterogeneous catalytic reaction, in particular to a preparation method of isononanoic acid.
Background
The isononanoic acid has wide application, can be used as a raw material of a synthetic lubricant, a medical intermediate, a raw material of metal soap and metal processing liquid, is also suitable for modifying alkyd resin, can improve yellowing resistance and impact resistance, can be used for producing various isononanoic acid esters, can be used in the field of cosmetics, and can be used for different applications such as a paint drier, a vinyl stabilizer, a polyvinyl chloride stabilizer, a preservative, a tire bonding aid and the like. Isononanoic acid can be produced by oxidation of the corresponding aldehyde.
At present, metal salt homogeneous catalysts are mostly used for preparing acid by aldehyde oxidation. In patent CN200510054082.9, propionate is adopted in the preparation of propionic acid by propionaldehyde oxidationOr acetate or naphthenate as catalyst. The catalyst for preparing acid by aldehyde oxidation in the patent CN02151618.9 is homogeneous manganese salt. Hydroxylamine hydrochloride can also be used as a homogeneous catalyst in H2O2In the/HCl system, aliphatic aldehydes such as isononanal are efficiently oxidized to their corresponding carboxylic acids in refluxing acetonitrile or methanol. Fatty aldehyde is oxidized to prepare corresponding acid under the combined action of hydrogen peroxide and p-toluenesulfonic acid in the presence of beta-cyclodextrin. The homogeneous system has defects, or the reaction time is long, or the catalyst is dissolved in the reaction system and is difficult to recycle. The sulfonic acid resin is used as a catalyst, the hydrogen peroxide is used as an oxidant, and the aldehyde can be oxidized into corresponding acid, but the activity and the selectivity of the aldehyde are to be improved. The petrochemical oxidation engineering and technology book discloses that the catalyst for the oxidation of aldehydes to carboxylic acids can be acetate or naphthenate, such as: in the device for producing acetic acid by oxidizing acetaldehyde, manganese acetate is used as a catalyst, so that peroxyacetic acid generated during acetaldehyde oxidation is timely decomposed, and the accumulation, decomposition and explosion of the peroxyacetic acid are prevented. At the same time, the metal salt can promote the generation of free radicals, accelerate the initiation reaction of chains, shorten the induction period of the reaction, obviously shorten the reaction time, but along with the rapid progress of the exothermic reaction, the reaction is difficult to control, and the selectivity is reduced. For example, in the process of preparing propionic acid by oxidizing propionaldehyde, when manganese acetate, cobalt acetate, iron acetate, copper acetate and the like are used as catalysts, the influence of the catalysts on the selectivity of the product is large, and the selectivity is lower than that when the catalysts are not added.
With the continuous and intensive research, it can be found that in the method for synthesizing carboxylic acid by oxidizing aliphatic aldehyde and aromatic aldehyde, due to the existence of side reaction and the restriction of reaction conditions, most products have low purity, low yield and poor economic benefit, and are not beneficial to the industrial production.
Disclosure of Invention
The invention aims to provide a method for preparing isononanoic acid, which has mild reaction conditions and higher yield.
The purpose of the invention can be realized by the following technical scheme: a process for preparing isononanoic acid uses sulfonated mesoporous Si-C composite material as catalyst and hydrogen peroxide as oxidant to oxidize isononanoic aldehyde into isononanoic acid.
Further, the preparation method of isononanoic acid specifically comprises the following steps:
(1) mixing isononanal, acetonitrile, hydrogen peroxide and a sulfonated mesoporous silicon-carbon composite material, heating and reacting;
(2) after the reaction is finished, cooling the reaction mixture to room temperature;
(3) evaporating acetonitrile in the reaction mixture, adjusting the reaction mixture to be alkaline by using a sodium hydroxide solution, and extracting by using an organic solvent;
(4) acidifying the water phase obtained by extraction with hydrochloric acid, and extracting with an organic solvent;
(5) the organic phase from the extraction was collected and evaporated to give nonanoic acid.
Furthermore, the reaction temperature in the step (1) is 40-80 ℃, and the reaction time is 1.5-2.5 h;
the concentration of the sodium hydroxide solution in the step (3) is 1.8-2.2 mol/L, and the pH of the reaction mixture is adjusted to 7.5-8.5;
the concentration of hydrochloric acid in the step (4) is 5.5-6.5 mol/L, and the pH value of the water phase is adjusted to 1.8-2.2;
the organic solvent used for extraction includes ethyl acetate.
The concentration of the hydrogen peroxide is 25-35 wt%, and the molar ratio of the sulfonated mesoporous silicon-carbon composite material to the hydrogen peroxide to the isononanal is 0.04-0.16: 1-6: 1.
The preparation process of the sulfonated mesoporous silicon-carbon composite material comprises the following steps:
(1) preparing mesoporous silicon by adopting a sol-gel method;
(2) adding concentrated sulfuric acid into the mesoporous silicon;
(3) loading sucrose on the mesoporous silicon treated by concentrated sulfuric acid in the step (2) by adopting a chemical dipping method;
(4) carrying out carbonization treatment on the sucrose-loaded mesoporous silicon to obtain a mesoporous silicon-carbon composite material;
(5) carrying out hydrothermal sulfonation treatment on the mesoporous silicon-carbon composite material to obtain the sulfonated mesoporous silicon-carbon composite material.
Further, the preparation process of the sol-gel method in the step (1) is specifically as follows:
the first step is as follows: adding dodecylamine into a mixed solution of deionized water, hydrochloric acid and ethanol, and uniformly mixing to prepare a solution A;
the second step is that: uniformly mixing isopropanol and tetraethoxysilane to prepare a solution B;
the third step: slowly dripping the solution B into the solution A under strong stirring;
the fourth step: crystallizing, filtering, washing, drying, grinding and roasting to obtain the mesoporous silicon.
Furthermore, the molar ratio of the deionized water to the hydrochloric acid to the ethanol to the dodecylamine in the first step is 120-130: 0.06-0.08: 20-24: 1;
the volume ratio of the isopropanol to the ethyl orthosilicate in the second step is 0.3-0.4: 1;
and in the third step, the volume ratio of the solution A to the solution B is 3-4: 1.
And fourthly, crystallizing at the temperature of 40-50 ℃ for 18-24 hours, drying at the temperature of 90-110 ℃ for 8-12 hours, grinding to obtain the powder with the granularity of 200-800 meshes, roasting at the temperature of 500-600 ℃ for 9-11 hours.
The process of adding the concentrated sulfuric acid into the mesoporous silicon in the step (2) is specifically as follows: ultrasonically oscillating the mesoporous silicon prepared in the step (1) in water, adding 98% concentrated sulfuric acid, and continuing to ultrasonically oscillate;
the sucrose loading method in the step (3) specifically comprises the following steps: adding sucrose into the mixture of concentrated sulfuric acid and mesoporous silicon obtained in the step (2), stirring to completely dissolve the sucrose, soaking for a period of time at constant temperature, and then drying and grinding the mixture;
the carbonization treatment process in the step (4) is specifically as follows: and (4) carrying out primary carbonization on the ground product obtained in the step (3), and then carrying out high-temperature carbonization under the protection of inert gas to obtain the mesoporous silicon-carbon composite material.
Further, the molar ratio of the concentrated sulfuric acid to the water to the mesoporous silicon in the step (2) is 0.1-0.2: 6-8: 1; the mol ratio of the sucrose to the mesoporous silicon in the step (3) is 1.2-1.4: 1, the constant-temperature dipping temperature is 35-45 ℃, the dipping time is 8-12 hours, the drying temperature is 90-110 ℃, the drying time is 5-6 hours, and the grinding granularity is 200-800 meshes; and (4) performing primary carbonization at the temperature of 150-170 ℃ for 5-7 h, performing high-temperature carbonization at the temperature of 750-850 ℃ for 5-7 h.
The hydrothermal sulfonation treatment process in the step (5) comprises the following specific steps: adding concentrated sulfuric acid into the mesoporous silicon-carbon composite material obtained in the step (4) under the protection of inert gas, heating and refluxing, cooling to room temperature after the reaction is finished, diluting, filtering, washing the reaction solution to obtain a concentrated sulfuric acid-treated mesoporous silicon-carbon composite material, then transferring the concentrated sulfuric acid-treated mesoporous silicon-carbon composite material into a hydrothermal reaction kettle, carrying out hydrothermal reaction for a period of time, washing the product to be neutral, and drying to obtain the sulfonated mesoporous silicon-carbon composite material. Further, the mass ratio of the mesoporous silicon-carbon composite material to concentrated sulfuric acid is 0.02-0.03: 1, the heating reflux temperature is 50-70 ℃, the time is 15-16 h, the hydrothermal reaction temperature is 190-210 ℃, the hydrothermal reaction time is 2-4 h, and the drying temperature is 90-110 ℃.
Compared with the prior art, the invention has the following advantages:
1. the reaction conditions required by catalytic oxidation of aldehydes are mild, and a high yield can be obtained at 40-80 ℃;
2. the sulfonated mesoporous silicon-carbon composite material catalyst prepared by the invention is easy to separate and recycle, and has stable performance;
3. the sulfonated mesoporous silicon-carbon composite material catalyst prepared by the invention has large specific surface area and pore volume, and is an excellent environment-friendly catalyst;
4. the method has the advantages of few byproducts, high product purity, high yield and good economic benefit;
5. the preparation method disclosed by the invention is simple, high in safety and small in environmental pollution, and accords with the green development concept.
Detailed Description
The following examples are given to illustrate the present invention, and the following examples are carried out on the premise of the technical solution of the present invention, and give detailed embodiments and specific procedures, but the scope of the present invention is not limited to the following examples.
Example 1
Preparing a sulfonated mesoporous silicon-carbon composite material catalyst:
into a 150ml three-necked flask, 32.4ml of deionized water, 1.0ml (1 mol/L) was placed-1) The aqueous solution of the compound (A) and 19.0ml of absolute ethyl alcohol are mixed uniformly, 2.60g of dodecylamine is added, and the mixture is stirred in a water bath at the temperature of 45 ℃ for 30 minutes to prepare a solution A. 3.8ml of isopropanol and 11.1ml of ethyl orthosilicate are added into a dropping funnel and mixed evenly to prepare a solution B. Slowly dripping the solution B into the solution A under strong stirring, and crystallizing in a water bath at 50 ℃ for 20 hours. The sample was poured out and filtered, and washed thoroughly with deionized water to remove chloride ions. And drying the filter cake in a drying oven at 100 ℃ for 10 hours, taking out the filter cake, grinding the filter cake, transferring the filter cake into a muffle furnace, and roasting the filter cake at 550 ℃ for 10 hours to obtain a mesoporous silicon sample. Weighing 1g of mesoporous silicon sample, adding 12ml of water into a beaker, carrying out ultrasonic oscillation for 1.5 hours, adding 0.22g of 98% concentrated sulfuric acid, carrying out ultrasonic oscillation for 0.5 hour, then adding 1.65g of cane sugar, stirring to completely dissolve the sugar, and soaking in a water bath at 40 ℃ for 10 hours at constant temperature. And (4) moving the mixture into an oven, and drying the mixture for 5 to 6 hours at the temperature of 100 ℃. Grinding the dried sample, transferring into a crucible, roasting in a muffle furnace at 160 ℃ for 6 hours for primary carbonization, and then carrying out carbonization on the carbonized product in N2Carbonizing at 800 deg.c for 6 hr under protection to obtain the mesoporous Si-C composite material.
Then weighing about 1g of mesoporous silicon-carbon composite material, placing the mesoporous silicon-carbon composite material in a 100ml three-neck flask, adding 20ml of concentrated sulfuric acid and N2Under protection, heating and refluxing for 15-16 h in an oil bath, cooling to room temperature after reaction, diluting the reaction solution with 200ml of deionized water, performing suction filtration, washing with 80 ℃ distilled water for 3 times, transferring into a hydrothermal reaction kettle, performing hydrothermal reaction at 200 ℃ for 3h, and washing with distilled water until the pH of the filtrate is 7. Drying the sample at 100 ℃ to prepare the sulfonated mesoporous silicon-carbon composite.
Example 2
In this embodiment, the sulfonated mesoporous silicon-carbon composite material prepared in example 1 is used in the catalytic oxidation of isononanal to prepare isononanoic acid, and the specific process is as follows: adding 2g of isononanal, 4g of acetonitrile, 4g of 30 wt% hydrogen peroxide and 0.08g of catalyst into a 25ml single-neck round-bottom flask, heating in an oil bath to control the reaction temperature to be 288K, starting timing after the temperature rises to 313K, cooling to room temperature after reacting for 2h, evaporating the solvent in the reaction mixture through rotary evaporation, adjusting the pH to be 8 by using 2mol/L NaOH solution, extracting by using ethyl acetate, acidifying the water phase by using 6mol/L HCl, adjusting the pH to be 2, extracting by using ethyl acetate, collecting the obtained organic phase, and finally performing rotary evaporation to obtain the carboxylic acid. The isononanoic acid yield was 53%.
Example 3
In this embodiment, the sulfonated mesoporous silicon-carbon composite material prepared in example 1 is used in the catalytic oxidation of isononanal to prepare isononanoic acid, and the specific process is as follows: adding 2g of isononanal, 4g of acetonitrile, 4g of 30 wt% hydrogen peroxide and 0.08g of catalyst into a 25ml single-neck round-bottom flask, heating in an oil bath to control the reaction temperature to be 288K, starting timing after the temperature rises to 330K, cooling to room temperature after reacting for 2h, evaporating the solvent in the reaction mixture through rotary evaporation, adjusting the pH to be 8 by using 2mol/L NaOH solution, extracting by using ethyl acetate, acidifying the water phase by using 6mol/L HCl, adjusting the pH to be 2, extracting by using ethyl acetate, collecting the obtained organic phase, and finally performing rotary evaporation to obtain the carboxylic acid. The isononanoic acid yield was 73%.
Example 4
In this embodiment, the sulfonated mesoporous silicon-carbon composite material prepared in example 1 is used in the catalytic oxidation of isononanal to prepare isononanoic acid, and the specific process is as follows: adding 2g of isononanal, 4g of acetonitrile, 4g of 30 wt% hydrogen peroxide and 0.12g of catalyst into a 25ml single-neck round-bottom flask, heating in an oil bath to control the reaction temperature to be 288K, starting timing after the temperature rises to 330K, cooling to room temperature after reacting for 2h, evaporating the solvent in the reaction mixture through rotary evaporation, adjusting the pH to be 8 by using 2mol/L NaOH solution, extracting by using ethyl acetate, acidifying the water phase by using 6mol/L HCl, adjusting the pH to be 2, extracting by using ethyl acetate, collecting the obtained organic phase, and finally performing rotary evaporation to obtain the carboxylic acid. The isononanoic acid yield was 79%.
Example 5
In this embodiment, the sulfonated mesoporous silicon-carbon composite material prepared in example 1 is used in the catalytic oxidation of isononanal to prepare isononanoic acid, and the specific process is as follows: adding 2g of isononanal, 4g of acetonitrile, 4g of 30 wt% hydrogen peroxide and 0.12g of catalyst into a 25ml single-neck round-bottom flask, heating in an oil bath to control the reaction temperature to be 288K, starting timing after the temperature rises to 350K, cooling to room temperature after reacting for 2h, evaporating the solvent in the reaction mixture through rotary evaporation, adjusting the pH to be 8 by using 2mol/L NaOH solution, extracting by using ethyl acetate, acidifying the water phase by using 6mol/L HCl, adjusting the pH to be 2, extracting by using ethyl acetate, collecting the obtained organic phase, and finally performing rotary evaporation to obtain the carboxylic acid. The isononanoic acid yield was 83%.
The embodiments described above are described to facilitate an understanding and use of the invention by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above embodiments, and those skilled in the art should make improvements and modifications within the scope of the present invention based on the disclosure of the present invention.