Tuprakay Seree, Liengcharernsit Winai
Environmental Engineering Department, Kasetsart University, 50 Phaholyothin Rd., Chatuchak, Bangkok 10900, Thailand.
J Hazard Mater. 2005 Sep 30;124(1-3):53-8. doi: 10.1016/j.jhazmat.2005.03.027.
Immobilized titania (TiO2) batch reactors reduced hexavalent chromium (Cr(VI)) in the form of potassium dichromate (K2Cr2O7) to trivalent chromium (Cr(III)) in aqueous solution at pH 3 under 171 W/m2 light intensity. The light source was a 125-W ultraviolet (UV) lamp. The Cr(VI) reduction showed zero-order kinetics (k0), while the Cr(VI) adsorption fitted with first-order kinetics (k(1st)). Adsorption capacity increased with increasing initial Cr(VI) concentration, and the area of immobilized TiO2 limited the reduction efficiency. The lifetime of fresh immobilized TiO2 was approximately 14 h. In addition, the regeneration of TiO2 with 3M sodium hydroxide (NaOH) was necessary to improve adsorption reaction.
固定化二氧化钛（TiO₂）间歇式反应器在171 W/m²光照强度、pH值为3的水溶液中，将重铬酸钾（K₂Cr₂O₇）形式的六价铬（Cr(VI)）还原为三价铬（Cr(III)）。光源为125瓦紫外线（UV）灯。Cr(VI)还原呈现零级动力学（k₀），而Cr(VI)吸附符合一级动力学（k(1st)）。吸附容量随初始Cr(VI)浓度的增加而增加，固定化TiO₂的面积限制了还原效率。新鲜固定化TiO₂的寿命约为14小时。此外，用3M氢氧化钠（NaOH）对TiO₂进行再生对于改善吸附反应是必要的。
