Promising application of SiC without co-catalyst in photocatalysis and ozone integrated process for aqueous organics degradation

SiC is a newly developed photocatalyst, but it is often used together with a co-catalyst rather than solely for its relatively low activity. Here we reported the high activity of a commercial SiC in a photocatalysis and ozone combined process (photocatalytic ozonation). The commercial SiC showed very weak activity in photocatalysis of oxalic acid (OA) and para-hydroxybenzoic acid (PHBA) degradation, and its performance in catalytic ozonation was also not satisfied. However, the organics degradation and mineralization rates dramatically increased in the SiC photocatalytic ozonation. The different operation parameters were optimized, and the main reactive radicals in this process and its generation pathways were studied. It was found that photo-generated electron reduction of ozone and oxygen are the main pathways to produce hydroxyl radical, which was responsible to the high oxidizing ability of this process.