Yuan Bao-Ling, Li Xiang-Zhong, Graham Nigel
Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hong Kong, China.
Water Res. 2008 Mar;42(6-7):1413-20. doi: 10.1016/j.watres.2007.10.010. Epub 2007 Oct 13.
The application of a combined ferrate-photocatalysis process for the aqueous degradation of dimethyl phthalate (DMP) has been studied. The behaviour of the Fe(VI)-TiO(2)-UV process at pH 9 in the presence and absence of dissolved oxygen (DO) has been compared and significant differences have been found. In comparative tests under N(2) and O(2) bubbling, the chemical reduction rate of ferrate as conduction band electron acceptor was similar, but the resulting degradation of DMP was substantially lower in the presence of oxygen. It is speculated that the presence of oxygen leads to the formation of Fe-O-(organic) complex species that adsorb to, and deactivate, the surface of the photocatalyst. The presence of surface-adsorbed complex species was indicated by FTIR spectroscopy and a reduced TiO(2) adsorption capacity for DMP. In the presence of typical environmental levels of DO ( approximately 9mgL(-1)), the Fe(VI)-TiO(2)-UV process achieved a modest degree of DMP degradation (40% in 120min).
研究了高铁酸盐-光催化联合工艺对水中邻苯二甲酸二甲酯（DMP）的降解效果。比较了在pH为9且存在和不存在溶解氧（DO）的情况下Fe(VI)-TiO₂-UV工艺的行为，发现了显著差异。在N₂和O₂鼓泡的对比试验中，高铁酸盐作为导带电子受体的化学还原速率相似，但在有氧条件下DMP的降解率显著降低。据推测，氧的存在导致形成Fe-O-(有机)络合物，该络合物吸附在光催化剂表面并使其失活。傅里叶变换红外光谱（FTIR）和TiO₂对DMP吸附容量的降低表明了表面吸附络合物的存在。在典型环境溶解氧水平（约9mgL⁻¹）下，Fe(VI)-TiO₂-UV工艺对DMP的降解程度适中（120分钟内降解40%）。
