A kind of process method for preparing acrylic acid by one-step oxidation of propylene

Abstract

A process for preparing acrylic acid by one-step oxidation of propylene, which relates to a method for preparing acrylic acid, comprising the following process: mixing propylene with an oxidant and an inert gas, and the volume ratio of propylene / oxidant / inert gas is 1 / 2~15 / 4~20 , after mixing evenly, pass it into a fixed-bed reactor equipped with a catalyst for reaction, wherein the mass space velocity of propylene is 0.1~1h-1, and the reactor pressure is 0.1~1.5? MPa, the reaction temperature is 300~450°C; the reaction product is cooled by a condenser to obtain a liquid phase product, which is an aqueous solution containing acrylic acid. The present invention adopts the one-step catalytic oxidation method of propylene under pressurized conditions to prepare acrylic acid and the corresponding multi-metal oxide catalyst, which can not only increase the production strength of the reactor, reduce equipment investment, but also the yield of acrylic acid is significantly higher than normal pressure one-step oxidation. At the same time, the reaction system has higher conversion rate and selectivity.

Description

technical field [0001] The invention relates to a method for preparing acrylic acid, in particular to a process for preparing acrylic acid by pressurizing one-step catalytic oxidation of propylene. Background technique [0002] Acrylic acid contains unsaturated double bonds and is mainly used to synthesize acrylate and polyacrylic acid, and is an important chemical raw material. Polyacrylic acid can be used in sanitary materials, detergents, dispersants, flocculants and thickeners, etc.; acrylates are used in synthetic coatings, adhesives, imitation, paper, leather and plastic additives. With the enrichment and development of downstream products of acrylic acid, the demand for superabsorbent resin and coatings is increasing, and the demand and production capacity of acrylic acid are also increasing worldwide. [0003] The production method of acrylic acid has gone through several different stages such as chlorohydrin method, cyanohydrin method, high-pressure Reppe method, e...

AI Technical Summary

Problems solved by technology

Simultaneously these methods or existence acrylic acid yield is low, or exist catalyst preparation complex used, and need to use the problems such as poisonous and inflammable raw material such as tetraethoxysilane, triethylsilane, ethoxygermanium etc.