Patent ID: 7332626
Filing Date: 2008-02-19
Classification: B01D,C07C

Abstract:
1. A method for producing (meth)acrylic acid by a procedure comprising the steps of subjecting raw material of (meth)acrylic acid to a reaction of catalytic gas phase oxidation, absorbing (meth)acrylic acid, separating a gas discharged from the absorbing step into a recycle gas and a waste gas, cooling said recycle gas and circulating the recycle gas to a reactor and discarding the waste gas to outside of the system, wherein the concentration of a condensable substance contained in the recycle gas is lower than the concentration of a condensable substance contained in the waste gas, and said cooling step induces condensation of at least part of a condensable substance contained therein in the form of a condensate and consequently lowers the concentration of the condensable substance contained in said gas, and removes water content or acid content or both from the recycle gas.