Method for producing azodiisobutyronitrile from hydrobromic acid and hydrogen peroxide under action of catalyst

Abstract

The invention belongs to the technical field of chemical engineering, and particularly relates to a method for producing azodiisobutyronitrile from hydrobromic acid and hydrogen peroxide under the action of a catalyst. The method comprises the following steps: adding a hydrobromic acid solution, diisobutyronitrile hydrazine and a catalyst into a reaction kettle to form two phases; stirring the material, reacting the hydrogen peroxide with hydrobromic acid to generate bromine, reacting the bromine with diisobutyronitrile hydrazine under the action of a catalyst to generate azodiisobutyronitrile and hydrobromic acid, reacting the hydrobromic acid with the hydrogen peroxide dropwise added thereafter to generate bromine, continously reacting the bromine with diisobutyronitrile hydrazine to generate azodiisobutyronitrile and hydrobromic acid, and when no diisobutyronitrile hydrazine exists in the solution, and ending the reaction to finally form a mixed phase containing azodiisobutyronitrile and a hydrobromic acid solution. The mother liquor obtained after the hydrobromic acid reaction can be recycled, all components contained in the mother liquor cannot be separated out or discharged, no redundant substances are generated, recycling of materials is achieved, the cost is saved, the economical efficiency is excellent, the reaction time is shortened by half, and energy consumption is greatly saved.

Description

Technical field: [0001] The invention belongs to the technical field of chemical industry, and in particular relates to a method for producing azobisisobutyronitrile by using hydrobromic acid and hydrogen peroxide under the action of a catalyst. Background technique: [0002] At present, the following three methods are mainly used in the production of azobisisobutyronitrile: [0003] 1. Chlorine gas oxidation method: first pass chlorine gas into the reaction kettle to react with diisobutyronitrile hydrazine to prepare azobisisobutyronitrile. The main shortcoming of this production method is: (1) flow process is relatively complicated, and control point is many; Utilization rate is low, a part of chlorine gas is wasted because it cannot react in time, and it is easy to produce nitrogen trichloride by-product, which is highly dangerous; (3) hydrochloric acid solution is used as solvent in the production process, and the solubility is poor, and the reaction time is too long (...

AI Technical Summary

Problems solved by technology

The main disadvantages of this production method are: (1) the flow process is relatively complicated, and there are many control points; the reaction process is not stable, the reaction end point is difficult to control, and it is easy to cause overoxidation, and there are many equipment used; (2) the chlorine gas in the production process Utilization rate is low, a part of chlorine gas is wasted because it cannot react in time, and it is easy to produce nitrogen trichloride by-product, which is highly dangerous; (3) hydrochloric acid solution is used as solvent in the production process, which has poor solubility and long reaction time (4) in the reaction process, a large amount of liquid caustic soda needs to be consumed to process waste tail gas, which wastes chemical reagents; (5) the product needs to be washed, and 1 ton of product is washed with 20 to 30 tons of water, which is a serious waste of water resources, and also A large amount of waste acid water will be produced

The main disadvantages of this production method are: (1) the reaction process is not stable, it is easy to cause concentrated reaction, generate a large amount of heat, cause the decomposition of azobisisobutyronitrile generated, and cause production accidents; (2) raw materials and products are mixed together , the reaction end point is not easy to control; (3) the utilization rate of hydrogen peroxide is low, and a part of hydrogen peroxide is wasted because it cannot react in time; (4) dilute sulfuric acid is used as solvent in the production process, the solubility is poor, and the reaction time is too long; (5) The wastewater generated during the reaction process contains a large amount of sulfuric acid solid salt and dilute sulfuric acid, which is not easy to recycle, and the treatment cost is relatively high

The disadvantages of this production method are: (1) the reaction time is too long, and the generated product decomposes in an oxidizing environment for too long; The danger of organic solvents caused by material decomposition (3) The reaction between bromine and diisobutyronitrile hydrazine is too slow, resulting in waste of energy consumption (4) Bromine in excess mother liquor will volatilize, causing environmental impact (5) Excess mother liquor wastewater The presence of bromine can easily cause damage to microorganisms and plants