Oxidation of phenol in aqueous solution with copper catalysts

The oxidation of phenol in aqueous phase over four different catalysts base d on copper has been studied in a basket stirred tank reactor. Runs have be en carried out at 140 degreesC and 16 bar of oxygen pressure, with a cataly st loading of 60 g/l and at an initial acidic pH. Phenol, total organic car bon and some intermediates have been measured with the reaction time. The i mprovement achieved with the catalyst is established by comparison with a b lank (reaction without catalyst). The commercial catalyst Engelhard Cu-0203 T (CuO, 67-77%, Cu chromite, 20-30%, graphite sint., 1-3%) was found to be the most active catalyst with an acceptable mechanical and chemical stabili ty. Copper leaches from the catalyst are higher when the mineralization of the acid intermediates does not occur (lower values of pH are obtained). (C ) 2001 Elsevier Science B.V. All rights reserved.