阅读说明：本技术 一种氧化裂解不饱和脂肪酸制备二元酸的连续氧化方法 (Continuous oxidation method for preparing dibasic acid by oxidative cracking of unsaturated fatty acid ) 是由 李伟 钮腾飞 蒋惠亮 王刚 赵杰 于 2020-08-26 设计创作，主要内容包括：本发明涉及一种氧化裂解不饱和脂肪酸制备二元酸的连续氧化方法,将不饱和脂肪酸溶解在有机溶液中为A溶液,将催化剂与氧化剂混合均匀为B溶液,分别将A、B溶液置入微通道反应器,反应1-10分钟,收集反应液,得到氧化裂解产物；然后通过分液得到油状液体产物,用沸水萃取,萃取后的水相经低温结晶后干燥得到二元酸产品；所述氧化剂常采用过氧化氢；本发明的有益效果是：通过采用微通道反应器作为反应整体,具有温度控制精确,反应器体积小,反应时间短,转化率和收率高,安全性好,易于放大等特点,实现了反应的连续化实施。(The invention relates to a continuous oxidation method for preparing dibasic acid by oxidative cracking of unsaturated fatty acid, which comprises the steps of dissolving the unsaturated fatty acid in an organic solution to obtain a solution A, uniformly mixing a catalyst and an oxidant to obtain a solution B, respectively placing A, B solutions into a microchannel reactor for reaction for 1-10 minutes, and collecting reaction liquid to obtain an oxidative cracking product; then obtaining an oily liquid product through liquid separation, extracting the oily liquid product by using boiling water, and drying the extracted water phase after low-temperature crystallization to obtain a dibasic acid product; the oxidant is hydrogen peroxide; the invention has the beneficial effects that: the microchannel reactor is used as a reaction whole, has the characteristics of accurate temperature control, small reactor volume, short reaction time, high conversion rate and yield, good safety, easy amplification and the like, and realizes the continuous implementation of the reaction.)

1. A continuous oxidation method for preparing dibasic acid by oxidative cracking of unsaturated fatty acid is characterized in that:

dissolving unsaturated fatty acid in an organic solution to obtain an A solution, uniformly mixing a catalyst and an oxidant to obtain a B solution, respectively placing A, B solutions into a microchannel reactor, reacting for 1-10 minutes, and collecting reaction liquid to obtain an oxidative cracking product;

then obtaining an oily liquid product through liquid separation, extracting the oily liquid product by using boiling water, and drying the extracted water phase after low-temperature crystallization to obtain a dibasic acid product;

the oxidant is usually hydrogen peroxide.

2. The continuous oxidation process for the oxidative cleavage of unsaturated fatty acids to produce dibasic acids of claim 1, wherein: the microchannel structure of the microchannel reactor is a straight-flow tubular structure.

3. The continuous oxidation process for the oxidative cleavage of unsaturated fatty acids to dibasic acids according to claim 1 or 2, wherein: the section of the micro-channel structure of the micro-channel reactor is a circular structure, and the inner diameter of the micro-channel structure is 0.8-2.65 mm.

4. The continuous oxidation process for the oxidative cleavage of unsaturated fatty acids to dibasic acids according to claim 1 or 2, wherein: the reaction temperature of the microchannel reactor is 70-120 ℃, the solution flow rate is 0.5-10ml/min, and the reaction time is 1-10 minutes.

5. The continuous oxidation process for the oxidative cleavage of unsaturated fatty acids to produce dibasic acids of claim 1, wherein: the organic solvent is any one or more of tert-butyl alcohol, ethyl acetate, formic acid, nonanoic acid and water.

6. The continuous oxidation process for the oxidative cleavage of unsaturated fatty acids to produce dibasic acids of claim 1, wherein: the catalyst is one or more of phosphotungstic acid, phosphovanadium molybdate, tungstic acid and tungsten oxide.

7. The continuous oxidation process for the oxidative cleavage of unsaturated fatty acids to produce dibasic acids of claim 1, wherein: the molar concentration of the unsaturated fatty acid in the solution A is 0.1-1 mol/L.

8. The continuous oxidation process for the oxidative cleavage of unsaturated fatty acids to produce dibasic acids of claim 1, wherein: the dosage of the catalyst is 2-12% of the mass of the unsaturated fatty acid.

9. The continuous oxidation process for the oxidative cleavage of unsaturated fatty acids to produce dibasic acids of claim 1, wherein: the molar ratio of the unsaturated fatty acid to the oxidant is 1: 4-10.

10. The continuous oxidation process for the oxidative cleavage of unsaturated fatty acids to produce dibasic acids of claim 1, wherein: the mass concentration of the oxidant is 30-50%.

Technical Field

The invention relates to the technical field of chemical synthesis, in particular to a continuous oxidation method for preparing dibasic acid by oxidative cracking of unsaturated fatty acid.

Background

The organic dibasic acid with medium chain length has high use value, can be used for preparing high polymer nylon 9 and nylon 69, and has the advantages of wear resistance, corrosion resistance, excellent low-temperature performance and the like; the synthesized plasticizers such as dioctyl azelate, isobutyl azelate and the like have the advantages of good heat resistance, cold resistance, low viscosity, high boiling point, difficult volatilization, high plasticizing efficiency and the like; the synthesized lubricants such as dioctyl azelate, didecyl azelate, ditridecyl azelate and the like have high flash point and good viscosity-temperature characteristics. Can be used for treating skin hyperpigmentation, pigmentation, melanoma, etc. in medicine and medicine, and can also be used for treating acne, etc. in clinic; it can also be used for producing adhesives, solvents, corrosion inhibitors, cosmetics, etc.

At present, although the ozone oxidation cracking method mainly adopted in industry has mild condition and no secondary pollution, the energy consumption is high, the selectivity is poor, and the safety risk exists. Therefore, the method develops a more environment-friendly, cheap and efficient unsaturated fatty acid oxidative cracking system, and has important significance for sustainable development and industrial structure transformation of the grease chemical industry. The hydrogen peroxide is simple and convenient to use, only generates water in the reaction process, is environment-friendly and pollution-free, and is an ideal oxidant.

Most of the existing methods for preparing the dibasic acid by using hydrogen peroxide or ozone for oxidative cracking of unsaturated fatty acid have the problems of long reaction time, high temperature, requirement of additives and the like.

Disclosure of Invention

In order to solve the defects in the prior art, the invention aims to provide a continuous oxidation method for preparing dibasic acid by oxidative cracking of unsaturated fatty acid.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a continuous oxidation method for preparing dibasic acid by oxidative cracking of unsaturated fatty acid is characterized in that:

dissolving unsaturated fatty acid in an organic solution to obtain an A solution, uniformly mixing a catalyst and an oxidant to obtain a B solution, respectively placing A, B solutions into a microchannel reactor, reacting for 1-10 minutes, and collecting reaction liquid to obtain an oxidative cracking product;

then obtaining an oily liquid product through liquid separation, extracting the oily liquid product by using boiling water, and drying the extracted water phase after low-temperature crystallization to obtain a dibasic acid product;

the oxidant is usually hydrogen peroxide.

The microchannel structure of the microchannel reactor is a straight-flow tubular structure.

The section of the micro-channel structure of the micro-channel reactor is a circular structure, and the inner diameter of the micro-channel structure is 0.8-2.65 mm.

The reaction temperature of the microchannel reactor is 70-120 ℃, the solution flow rate is 0.5-10ml/min, and the reaction time is 1-10 minutes.

The organic solvent is any one or more of tert-butyl alcohol, ethyl acetate, formic acid, nonanoic acid and water.

The catalyst is one or more of phosphotungstic acid, phosphovanadium molybdate, tungstic acid and tungsten oxide.

The molar concentration of the unsaturated fatty acid in the solution A is 0.1-1 mol/L.

The dosage of the catalyst is 2-12% of the mass of the unsaturated fatty acid.

The molar ratio of the unsaturated fatty acid to the oxidant is 1: 4-10.

The mass concentration of the oxidant is 30-50%.

The invention has the beneficial effects that: the microchannel reactor is used as a reaction whole, has the characteristics of accurate temperature control, small reactor volume, short reaction time, high conversion rate and yield, good safety, easy amplification and the like, and realizes the continuous implementation of the reaction.

Drawings

The invention is further illustrated with reference to the following figures and examples.

FIG. 1 is a schematic flow chart of the method of the present invention.

Detailed Description

The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will become apparent to those skilled in the art from the present disclosure.