Ozone catalytic oxidation capacity of Ti-Co@Al2 O3 for the treatment of biochemical tailwater from the coal chemical industry.

Abstract

A Ti-Co@γ-Al2 O3 composite catalyst was prepared using impregnation and sol-gel methods to degrade biochemical tailwater from the coal chemical industry, and its preparation conditions (active component doping ratio, load times, and calcination temperature) were optimized through single-factor experiments. The surface properties of the Ti-Co@γ-Al2 O3 composite catalyst and the crystal structure characteristics of the catalytically active components were characterized via scanning electron microscopy-energy dispersive spectrometry, X-ray diffraction, and X-ray fluorescence. The effects of reaction time, initial pH, ozone aeration, and catalyst dosage on degradation performance were investigated through an experiment on the catalytic ozonation degradation of biochemical tail water. Results showed that the optimal conditions were as follows: reaction time of 30min, pH of 8.2, ozone aeration of 30mg/min, and catalyst dosage of 20g/L. The total phenol and total organic carbon removal rates for biochemical tailwater were 66.1% and 57.6%, respectively, in the catalytic system. The mechanism of degradation of organic pollutants by catalytic ozonation was investigated by adding tert-butanol to the catalytic ozone oxidation system. The degradation of chemical oxygen demand in biochemical tailwater was caused primarily by the synergy between the Ti-Co@γ-Al2 O3 catalyst and ozone. PRACTITIONER POINTS: Ti-Co/γ-Al2 O3 catalyst was prepared for the catalytic oxidation of biochemical tail water. The optimal removal rates of total phenol and TOC were 67.7% and 58.8%, respectively. The organic matter was degraded rapidly and efficiently after 5min of ozone catalytic oxidation reaction. It provides theoretical guidance for the practical application of ozone catalytic oxidation.