In order to carry out decolorization, sludge protein solution, a dark brown close to black solution from activated sludge, was subjected to 60Co γ-ray irradiation in the presence of hydrogen peroxide. UV/Vis spectrophotometric method was used to investigate the effect of H2O2 on the coloration apparent kinetics and rate constants of sludge protein solution under γ-ray irradiation. In addition, the effects of irradiation dose, initial sludge protein solution concentration, and pH value on the decolorization efficiency of sludge protein solution were studied. Results showed that the decolorization apparent kinetics of sludge protein solution was a first-order reaction. The solution decolorization percentage increased with the increase of irradiation dose or the decrease of initial sludge protein solution concentration. The examination results of pH value showed that the sludge protein solution could be more efficiently decolorized in alkaline media than in acid media. Moreover, sensory evaluation and foamability analysis indicated that irradiated samples under H2O2 oxidation showed better sensory score and foamability.

A large amount of residue including benzoic acid, benzyl benzoate and fluorenone can form in the production of benzoic acid by oxidizing toluene. To recycle the resources and reduce secondary pollution, the treatment of benzoic acid residue was carried out to obtain the three purified materials by flash-vacuum distillation combination method, and the influence of the operating parameters, such as the top pressure, reflux ratio and top and bottom temperatures was investigated to obtain the best operating conditions. The experimental results show that the benzoic acid purity can reach 97% through distillation under the following conditions: the top pressure is 1 600 Pa, the bottom temperature is 190–200 °C, the top temperature is 130–135 °C, and reflux ratio is 5:1. The best operating conditions for benzyl benzoate distillation column are: the top pressure is 400 Pa, bottom temperature is 250–260 °C, the top temperature is 150–160 °C, and reflux ratio is 5:1. The benzyl benzoate purity can reach 95% and the fluorenone purity can reach 92%. When refined by melt crystallization, the benzoic acid purity can be improved up to 99.6%, and the purities of benzyl benzoate and fluorenone are both above 95%.

The features of nickel foam packing were introduced. The hydrodynamic performance and mass transfer efficiency of nickel foam packing were measured and a mass transfer equation was established to predict the HETP results. Comparing with CDG1700X stainless steel wire mesh packing, nickel foam packing has better hydrodynamic performance and mass transfer efficiency, the mass transfer efficiency is 40% higher than the CDG1700X stainless steel wire mesh packing, and pressure drop is 20% of the CDG1700X stainless steel wire mesh packing.