Patent ID: 8178719

Claim:
A process for producing acrylic acid, comprising the steps of: a) vaporizing a raw material comprising an aqueous glycerol solution to generate a first gas, wherein said aqueous glycerol solution has a water content of not more than 50% by weight; b) applying a dehydration reaction to glycerol in a gas phase that includes said first gas; then c) applying a gas phase oxidation reaction to a gaseous reaction product formed by the dehydration reaction to obtain said acrylic acid; and d) wherein the dehydration reaction and the gas phase oxidation reaction are conducted in a tandem-type reactor comprising the two reaction tubes which are linked to each other, where the two reaction tubes are filled with a catalyst for the dehydration reaction and a catalyst for the gas phase oxidation reaction respectively, and where the dehydration reaction and the gas phase oxidation reaction are separately conducted in their respective tubes.