Application of catalytic wet air oxidation for the treatment of H-acid manufacturing process wastewater

Four types of powder catalysts whose main active components are copper (Cu), cerium (Ce), cadmium (Cd) and cobalt-bismuthide (Co-Bi) are prepared with the method of the co-deposition and are evaluated through the catalytic wet air oxidation (CWAO) treatment of H-acid solution. The comparison of the efficiencies of different catalysts shows that Ce3Cu1 (3:1) catalyst is the best one. When the reaction temperature is 200°C, oxygen partial pressure is 3 MPa, pH value is 12, and reaction time is 30 min, the COD removal rate is over 90%. All the H-acid is decomposed in 5 min and is oxidized into NH4+, SO42−, formic acid, acetic acid and other end products. The pH value can greatly affect the COD removal and the production of organic acid. CWAO process not only can get a high reaction rate, but also can oxidize the short-chain organic acid.