A production method of acrylic acid

摘要

A method for producing acrylic acid from propylene at high efficiency by a two-stage catalytic oxidation using a single fixed bed shell-and-tube heat exchanger type reactor is provided. The shell space of the reactor is divided into an upper space and lower space by a partition plate, allowing a heating medium to circulate independently in each of the spaces, and carrying out the vapour phase oxidation under specific conditions which include providing a first stage catalyst layer in a lower portion of each of the reaction tubes, a second stage catalyst layer in an upper portion thereof and an inert substance layer there between, and making the void ratio of the inert substance layer from 40-99.5%.