天然水体主要本底成分对催化臭氧氧化草酸的影响

采用浸渍法制备了Fe2O3负载活性炭（Fe2O3/AC）催化剂，考察了Fe2O3/AC催化臭氧氧化草酸的活性以及天然水体主要本底成分对Fe2O3/AC催化臭氧氧化草酸的影响. 结果表明，臭氧氧化草酸过程中Fe2O3/AC显示了良好的催化活性，草酸的去除主要基于催化贡献. HCO3-、CO32-及腐殖酸对Fe2O3/AC催化臭氧氧化草酸体系均有抑制作用. HCO3-和CO32-加入使催化臭氧氧化体系pH升高，进而降低Fe2O3/AC催化臭氧氧化草酸的活性. 此外，HCO3-和CO32-也是羟基自由基抑制剂，HCO3-、CO32-对体系的抑制作用从侧面验证Fe2O3/AC催化臭氧氧化草酸遵循羟基自由基机理. 腐殖酸加入体系后，与草酸形成竞争吸附和竞争氧化，从而抑制草酸的降解.

Effect of Background Constituents on Catalytic Ozonation of Oxalic Acid

The aim of this research was to investigate catalytic activity of Fe2O3 loaded activated carbon catalyst (Fe2O3/AC) prepared by the dipping method, and the effect of background constituents on catalytic ozonation of oxalic acid. Fe2O3/AC showed good activity in ozonation of oxalic acid, and the removal of oxalic acid was mainly based on catalytic contribution. Some background constituents such as HCO3-, CO32- and humic acid could cause the inhibition of oxalic acid degradation in Fe2O3/AC catalytic ozonation. The addition of HCO3-, CO32- increased the pH value of system, and therefore the activity of Fe2O3/AC decreased. The inhibition of oxalic acid degradation indirectly proved that catalytic ozonation of oxalic acid in the presence of Fe2O3/AC followed the mechanism of hydroxyl radical oxidation. The humic acid competed with oxalic acid to be adsorbed and oxidized which led to the inhibition of oxalic acid degradation.