BACKGROUNDThe investigation of microwave-assisted heterogeneous catalytic oxidation of high-concentration dye effluent with novel catalyst (CuFe2O4/PAC) is promising in the field of industrial wastewater treatment compared with conventional advanced oxidation techniques which are very slow. RESULTA novel microwave catalyst, CuFe2O4 loaded on powdery activated carbon (CuFe2O4/PAC) was prepared and applied for microwave-assisted heterogeneous catalytic oxidation of high-concentration reactive azo dye Reactive yellow 3 (RY3). The results showed that it exhibited 74.5% degradation efficiency, 48.5% TOC removal of RY3 (200mgL(-1)) within 5min over a broad pH range from 3 to 11 and reduced the toxicity after degradation. The influences of initial pH, catalyst dosage, H2O2 concentration and reusability of catalyst on degradation were evaluated. The toxic potential during degradation was assessed by bioluminescence test. Moreover, center dot OH and O-2 center dot(-) were found to be the main active species involved in the system and a possible RY3 degradation mechanism was proposed. CONCLUSIONThis study found a microwave-assisted heterogeneous oxidation system with CuFe2O4/PAC to be highly efficient, stable, low toxicity and relevant in high-concentration dye wastewater treatment and industrial applications. (c) 2014 Society of Chemical Industry