Patent name: REMOVAL AND NEUTRALIZATION OF ACID CATALYST FROM PRODUCTS OF CUMENE HYDROPEROXIDE CLEAVAGE
Patent Number: US 5,510,543
April 23, 1996
The present invention is an improved method for the recovery of phenol from a cleavage mass resulting from the sulfuric acid cleavage of cumene hydroperoxide comprising neutralizing the cleavage mass, forming an aqueous phase and an organic phase, separating the organic phase into an acetone-rich stream and a phenol-rich stream, removing phenol tars from the phenol-rich stream and cracking the phenol tars wherein the improvement comprises maintaining the pH of the cleavage mass during neutralization between 4.0 and about 4.9 whereby the sulfuric acid is converted to the bisulfate salt and substantially no free sulfuric acid remains in the cleavage mass and corrosion of process equipment is reduced. As a result of this improved process, a phenol tar waste stream containing less than about 4 parts per million by weight of chromium is obtained.