阅读说明：本技术 一种用微通道反应器制备无水过氧乙酸溶液的方法 (Method for preparing anhydrous peroxyacetic acid solution by using microchannel reactor ) 是由 祁彦涛 屠常刚 刘春艺 李涛 于 2019-04-17 设计创作，主要内容包括：本发明提出一种用微通道反应器制备无水过氧乙酸溶液的方法。该方法包括将乙醛和催化剂溶于有机溶剂中作为物料1,将氧气或空气作为物料2,通入微通道反应器中,在60~90<Sup>o</Sup>C下,连续流合成无水过氧乙酸溶液,反应时间10~50s,压力2~6bar。与现有的常规釜式反应器相比,该工艺持液体积小,大大的减少了过氧乙酸的潜在危险性；反应时间大大缩短,而且传质传热均匀,无放大效应,收率和浓度均比釜式反应有较大的提高,很大程度上提高了生产效率和工艺的安全性。(The invention provides a method for preparing anhydrous peroxyacetic acid solution by using a microchannel reactor. The method comprises the steps of dissolving acetaldehyde and a catalyst in an organic solvent to serve as a material 1, introducing oxygen or air to serve as a material 2 into a microchannel reactor at a temperature of 60-90 DEG C o And C, continuously synthesizing the anhydrous peroxyacetic acid solution, wherein the reaction time is 10-50 s, and the pressure is 2-6 bar. Compared with the conventional kettle type reactor, the process has small liquid holding volume, and greatly reduces the potential danger of peroxyacetic acid; the reaction time is greatly shortened, the mass transfer and heat transfer are uniform, the amplification effect is avoided, the yield and the concentration are greatly improved compared with those of the kettle type reaction, and the production efficiency and the safety of the process are improved to a great extent.)

1. A process for preparing anhydrous peroxyacetic acid solution by using microchannel reactor includes dissolving acetaldehyde and catalyst in organic solvent as material 1, introducing oxygen or air as material 2 into microchannel reactor, and continuous flow synthesizing anhydrous peroxyacetic acid solution at proper temp.

2. The method of claim 1, wherein the organic solvent comprises ethyl acetate, acetone, chloroform.

3. The method of claim 1, wherein the catalyst comprises cobalt acetate and iron acetylacetonate in a molar amount of 3 to 6ppm based on the moles of acetaldehyde.

4. The method according to claim 1, wherein the flow rate of the liquid material 1 is 1-5 mL/min and the flow rate of the gas material 2 is 100-1000 mL/min under standard conditions.

5. The method of claim 1, wherein the suitable temperature is 60-90 deg.C^oC。

6. The process according to claim 1, wherein the reaction time is 10 to 50s and the pressure is 2 to 6 bar.

Technical Field

The invention relates to the technical field of synthesis of peroxyacetic acid, in particular to the technical field of preparation of anhydrous peroxyacetic acid solution by a microchannel reactor.

Background

Peracetic acid is a colorless liquid with a strong pungent odor. Since peracetic acid is a strong oxidizer, it is extremely unstable. The explosion is caused by slightly high temperature, or more than 45% concentration, or the presence of reducing agent and metal ions, so the production and the use need to be careful.

The industrial product peroxyacetic acid is generally a solution containing 18-23% of water and acetic acid, is mainly used as a bactericide, can be used for sterilizing infectious diseases, sterilizing drinking water, sterilizing fabrics, in the food industry and the like, and is a bactericide with a good popularization prospect. The peroxyacetic acid is also an important chemical raw material, and can be used in a series of reactions such as olefin epoxidation, oxidation of aromatic condensed rings, N-oxidation of pyridine and the like. Especially anhydrous peroxyacetic acid, can be used in more special oxidation reactions; however, peroxyacetic acid is potentially dangerous, and the conventional kettle-type preparation method limits the application range of the peroxyacetic acid due to the safety problem of the peroxyacetic acid.

The peroxyacetic acid is generally prepared by the following two methods:

1. the most common method is to mix acetic acid with 30-90% hydrogen peroxide and react for 4-36 hours under the catalysis of sulfuric acid or strong acid resin, so as to prepare aqueous solution of peroxyacetic acid, which generally contains substances such as acetic acid, strong acid, water and the like. Due to the potential danger of the tank reaction, CN103204793A reports a method for preparing peroxyacetic acid by using a continuous flow reactor, and CN103539770B, CN108250163A and the like also report application examples of the method for preparing peroxyacetic acid; although the method replaces a kettle type reactor with continuous flow, the obtained peroxyacetic acid is still aqueous solution and cannot meet the requirements of some anhydrous reactions.

2. Prepared by direct oxidation of acetaldehyde. Cobalt acetate and tartrate are generally used as catalysts, acetone or ethyl acetate is used as a solvent, and air or oxygen is directly introduced into an acetaldehyde solution to be oxidized to generate peroxyacetic acid. Also, the production and use of the kettle reaction is limited by its potential hazard.

Disclosure of Invention

In order to avoid the disadvantages of the above-mentioned production processes and to better prepare and use anhydrous peroxyacetic acid, the present invention proposes a process for preparing anhydrous peroxyacetic acid solutions using microchannel reactors, as shown in FIG. 1. Dissolving acetaldehyde and a catalyst in an organic solvent to serve as a material 1, introducing oxygen or air to serve as a material 2 into a microchannel reactor at a temperature of 60-90 DEG C^oAnd C, continuously synthesizing the anhydrous peroxyacetic acid solution, wherein the reaction time is 10-50 s, and the pressure is 2-6 bar. Compared with the conventional kettle type reactor, the process has small liquid holding volume, and greatly reduces the potential danger of peroxyacetic acid; the reaction time is greatly shortened, the mass transfer and heat transfer are uniform, the amplification effect is avoided, and the yield and the concentration are higher than those of the kettle type reactionThe production efficiency and the safety of the process are improved to a great extent.

Preferably, the catalyst comprises cobalt acetate and ferric acetylacetonate. The molar quantity and the number of moles of acetaldehyde are 3-6 ppm.

Preferably, the flow rate of the liquid material 1 is 1-5 mL/min, and the flow rate of the gas material 2 is 100-1000 mL/min under the standard condition.

Preferably, the suitable temperature is 60-90 deg.C^oC。

Preferably, the reaction time is 10 to 50s and the pressure is 2 to 6 bar.

The invention has the advantages that:

1. compared with the conventional kettle type reactor, the continuous flow synthesis of the microchannel reactor is adopted, so that the reaction liquid holding volume is small, the potential danger of the peroxyacetic acid is greatly reduced, and the intrinsic safety is realized.

2. The reaction time is greatly shortened from 1 to 2 hours of the kettle type reaction to 10 to 50 seconds; the yield is improved from about 50 percent of the kettle type reaction to about 70 percent. The mass transfer and heat transfer are uniform, the continuous production can be realized, and the amplification effect is avoided.

3. Provides a new continuous flow reaction method for the reaction of anhydrous peroxyacetic acid.

Description of the drawings:

FIG. 1 is a schematic diagram of the feed and discharge of an anhydrous peracetic acid solution prepared by using a microchannel reactor

Detailed Description

For a better understanding of the present invention, reference will now be made to the following examples. It should be understood that the following specific examples are illustrative of the invention only and are not limiting.