In this work, a coking wastewater was selected and a biochemical A(2)/O treatment device for fractional degradation was designed and employed. After each stage of the treatment, the products were analyzed through gas chromatography-mass spectroscopy (GC-MS) to determine their composition. Finally, AgNO3 + K2FeO4 was used as an advanced deep catalytic oxidation treatment. It was concluded from the analysis that cyclic organics could be degraded and the chemical oxygen demand (COD) was controlled within 50 mg.L(-)1, in line with the target value. Meanwhile, the spectra obtained from the GC-MS were in accordance with the conclusions reached based on the COD. The research results showed that all hard-degradable organics in coking wastewater could be eliminated through the A(2)/O bio-membrane treatment and the advanced treatment of making use of K2FeO4 as an oxidant and Ag+ as a catalyst, the catalytic efficiency with Ag+ as a catalyst of K2FeO4 was very high. Ag+ could evidently improve the oxidation capacity of K2FeO4 to wastewater in its short stability time, and this is an important innovation. (C) 2018 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.