抄録
Wet air oxidation (WAO) has emerged recently as an attractive alternative to conventional bio-technologies in respect of treating particularly toxic wastewater. WAO operation commonly requires high temperature (125-320°C) and pressure (0.5-20 MPa), which results in the increase in operating costs. In this regard, it has been experimentally verified that with the assistance of catalyst WAO can be conducted at much milder conditions. Heterogeneous types of catalyst allures the interests of more researchers as it can be conveniently separated and reused after the treatment. However, in many pragmatic cases of WAO by heterogeneous catalyst the leaching of catalyst can hardly be avoided, which brings the doubts on the accuracy of kinetics data thus obtained. In our kinetic study on phenol degradation using heterogeneous copper as the catalyst we adopted a batch stir reactor where the possible mass transfer effects can be sufficiently minimized. Given the possibility of copper leaching, we added saturated pH buffer solution into aqueous phenol and reduced phenol and catalyst initial concentrations. At length we successfully prevented copper leaching and estimated the reaction orders and activation energy in the oxygen partial pressure of 0.4-1.6 MPa and temperature range of 140-160deg;C.
