CATALYTIC WET AIR OXIDATION OF PHENOLIC WASTEWATERS

Treatment of high concentration chemical wastewater containing phenol and/or phenolic compounds by catalytic wet air oxidation (WAO) is stud ied. Experimental results indicate that over 99% w/w removal of phenol or phenolic compounds can be efficiently achieved by the catalytic WA O process utilizing hydrogen peroxide as homogeneous oxidant. It is ob served that the catalytic WAO process achieves high efficiency of phen ol or phenolic compound oxidation at lower operating temperature (150 degrees C or less) and pressure (0.5 MPa) than those of comparable con ventional WAO processes. The experimental data also show that the oxid ation reaction can be represented by a first-order, two-stage kinetics in terms of the component or COD concentration. The second-stage oxid ation was observed to be slower than the first-stage. The activation e nergies obtained for oxidation of phenol and phenolic coumpounds refle ct the speed of these two stage reactions.