Membrane enhanced COD degradation of pulp wastewater using Cu₂O/H₂O₂ heterogeneous Fenton process

Both activity and stability of the catalyst can be improved in heterogeneous Fenton reaction, in particular, with no limitation for the working pH and no production of the sludge. In this work, a combination of catalyst Cu₂O and pore-channel-dispersed H₂O₂ is proposed to treat the pulp wastewater. Degradation degree of CODs in the wastewater was up to 77% in the ceramic membrane reactor using Cu₂O powder (2.0 g·L^{− 1}) and membrane-feeding H₂O₂ (0.8 ml·L^{− 1}) within 60 min. Evolution of [rad]OH radical formation in the advanced oxidation process was analyzed with a fluorescent method. Utilization efficiency of H₂O₂ was successfully enhanced by 10% with the membrane distributor. Further on, the catalyst recyclability was evaluated in a five-cycle test. The concentration of copper ions being dissolved in the treated water was monitored with ICP. After Cu₂O/H₂O₂ (membrane) treatment the effluent is qualified to discharge with COD concentration lower than 15 mg·L^{− 1} with regard to the national standard GB25467-2010.