Process and catalyst for purifying phenol
View Patent ↗The goal of this invention is to produce phenol of high purity by conversion of impurities that are present in the starting phenol, which is produced by the decomposition of cumyl hydroperoxide. The indicated goal is achieved by purifying the phenol containing admixtures of aliphatic and aromatic carbonyl compounds with an aluminum zirconium catalyst.
1. A process for purifying raw phenol produced by the cumyl hydroperoxide cleavage method, which process comprises (i) contacting the raw phenol with an acidic aluminum oxide catalyst at a temperature of 90–200° C. and a raw material volumetric feed rate of 1–6 h −1 , and (ii) subsequently isolating purified phenol by distillation, wherein the aluminum oxide catalyst comprises a mixture of aluminum and zirconium oxides and sulfates and has a total content of aluminum and zirconium sulfate of from 5 to 15% by mass (calculated on the basis of SO 4 ions) and the catalyst has a total content of aluminum and oxide and sulfate of 5–30% mass (calculated on the basis of aluminum oxide).
2. The process according to claim 1 , wherein the catalyst consists essentially of a mixture of aluminum and zirconium oxides and sulfates.
3. The process according to claim 2 , wherein the catalyst is prepared by a process which comprises the steps of treating zirconium hydroxide twice using sulfuric acid in a first sulfation step and a second peptization step, and adding aluminum oxide in the peptizion step wherein aluminum oxide consists of a mixture of boehmite and pseudoboehmite in a mass ration of from 1:3 to 3:1.