Patent ID: 7253307

Claim:
A process for the preparation of methacrylic acid comprising: (i) providing a first raw material comprising acetone cyanohydrin and a second raw material comprising a material selected from the group consisting of oleum and a combination of sulfuric acid and oleum; (ii) hydrolyzing said first raw material and said second raw material to form a hydrolysis product; (iii) cracking said hydrolysis product to form a cracking product; (iv) reacting said cracking product and water in a plug flow acid formation reactor to form an acid formation product comprising methacrylic acid, wherein said acid formation reactor is maintained at a pressure of from 3.7 atmospheres to 7.8 atmospheres and a temperature between 80° C. and 170° C.; and (v) cooling said acid formation product to a temperature between 50° C. and 95° C. to form a two-phase product stream which is separable by gravitational settling.