Wet air oxidation of pretreatment of pharmaceutical wastewater by Cu2+ and [PxWmOy]q− co-catalyst system

This study concentrates on the pretreatment of real wastewater using catalytic wet air oxidation (CWAO). WO3− and PO43− contained in fosfomycin pharmaceutical wastewater (FPW) and Cu2+ contained in berberine pharmaceutical wastewater (BPW) were studied as CWAO influent. Mixture of this two streams were reused to form Cu2+ and [PxWmOy]q−, namely polyoxometalates (POMs) as co-catalyst system to treat themselves. Experiments were conducted to investigate the effects of the initial oxygen pressure and temperature on the COD (chemical oxygen demand), TOC (total organic carbon) removal and biodegradable enhancement, it was discovered that over 40% of COD and TOC removal can be easily realized in an hour of WAO oxidation at 523 K, 1.4 MPa. The BOD5/COD (BOD5, biochemical oxygen demand in 5 days) of this two pharmaceutical mixture ascended from nonexistent to maximum 0.41 depends on the optimal FPW:BPW volume ratio 4:1, to compose POM co-catalyst system. Organic pollutants were incompletely oxidized to propionic acid and other intermediates. Some properties (e.g., TGA, IR, XRF) of POM catalyst separated from effluent, were obtained to provide additional information.