Catalytic ozonation of hard COD in coking wastewater with Fe2O3/Al2O3-SiC: From catalyst design to industrial application

Development of robust, reactive, and inexpensive catalyst for pollutants abatement with catalytic ozonation is of great significance. Herein, the effect of a robust and easy-recovery catalyst, Fe 2 O 3 /Al 2 O 3 -SiC, for the catalytic ozonation of hardly biodegradable COD (hard COD) in coking wastewater had been explored. Al-O-Si bond formed on modified SiC through the substitution of hydrogen in surficial Si-OH groups by Al 3+ . The Lewis acid sites improved the adsorption of ozone and facilitated the formation of ·OH and O 2 · − . For coking wastewater treatment , the removal ratio of hard COD and the generation speed of hydroxyl radical (R ct ) in the catalytic ozonation process were 71% and 253% higher than those in the ozonation group, respectively. Ozone utilization increased from 0.44 g COD removed/g O 3 in the ozonation group to 1.42 g COD removed/g O 3 in the Fe 2 O 3 /Al 2 O 3 -SiC catalytic ozonation group. In a full-scale application, Fe 2 O 3 /Al 2 O 3 -SiC catalytic ozonation decreased the consumption of O 3 to 60 mg L −1 and decreased the operation cost by 50%. These results provided an approachable way for sharing the extraordinary capacity of ozone for contaminants remediation in industrial applications.