CeO2／O3催化氧化对滤后水中小分子副产物生成的影响

考察了连续流体系中，滤后水经氧化铈催化臭氧氧化（CeO2／O3）后小分子醛、酮、羧酸及酮酸副产物的生成情况．发现CeO2／O3明显提高了DOC和SUVA的去除率，醛、酮副产物的产量比单独O3氧化后的增加了8％，而羧酸和酮酸的产量却比单独O3氧化后的分别降低了28％和54％．羧基类副产物大幅降低的原因主要与CeO2表面Ce（Ⅳ）对羧基官能团较强的络合亲合力有关．CeO2／O3氧化后小分子副产物总量比单独O3氧化后的降低了23％，但用小分子副产物总量折算有机碳占DOC的比例来间接显示氧化后剩余DOC的可生物降解性，结果表明，CeO2／O3进一步提高了滤后水剩余DOc的可生化性．

Effect of Catalytic Ozonation with Supported Cerium Oxide on the Formation of Low Molecular Weight Oxidation By-Products of Filtered Surface Water

The aim of the work is to investigate the formation of the low molecular weight （LMW）oxidation by- products （i.e. aldehydes, ketones, carboxylic acids and ketoacids）after cerium oxide-catalyzed ozonation （CeO2/ O3） of filtered waters in a continuous flow reactor. Results showed that CEO2/O3 can evidently improve the reduction of the dissolved organic matter （DOC） and specific UV absorbance （SUVA）. Compared with ozonation alone, CEO2/O3 caused an increment of the formation of aldehydes and ketones by about 8%, and a significant reduction of the formation of carboxylic acids and ketoacids by 28% and 54%, respectively. The great reduction of carboxyl group by-products is mainly attributed to the high affinity of Ce （IV） to the carboxyl group on the surface of CeO2 during CEO2/O3 oxidation. The total production of LMW by-products reduced by 23%. However, the filtered water became more biodegradable after catalytic ozonation, because the percentage of total LMW by-produ：ts carbon in the final DOC after catalytic ozonation was higher than that after ozonation alone.