不同复合体系对含钛高炉渣光催化还原Cr(VI)的影响  

Effect of the Different Compound Systems on Photocatalytic Reduction of Cr(VI) by Titanium-Bearing Blast Furnace Slag

作　　者：雷雪飞[1] 薛向欣[1] 

机构地区：[1]东北大学材料与冶金学院,沈阳110004

出　　处：《化学学报》2008年第22期2539-2546,共8页Acta Chimica Sinica

基　　金：国家自然科学基金(No.50274025);教育部重大科技(No.307009);973计划(No.2007CB613504)资助项目.

摘　　要：采用煅烧的硫酸盐掺杂的含钛高炉渣(sulfate-modified titanium-bearing blast furnace slag,STBBFS)作为光催化剂,研究了Cr(VI)-柠檬酸[Cr(VI)-CA]复合体系和Cr(VI)-柠檬酸-硝酸铁[Cr(VI)-CA-FN]复合体系对STBBFS催化剂光催化活性的影响.结果表明:酸性条件下,不同复合体系对STBBFS催化剂光催化活性的促进作用按Cr(VI)-CA-FN复合体系>Cr(VI)-CA复合体系>Cr(VI)单一体系增强.Cr(VI)-CA复合体系在pH=2.5,反应50min后STBBFS催化剂光催化活性为0.426mg·min―1·g―1时将溶液中的Cr(VI)全部还原;而Cr(VI)-CA-FN复合体系在pH=2.5,反应16min后STBBFS催化剂光催化活性为1.2425mg·min―1·g―1时将溶液中的Cr(VI)全部还原.两种复合体系中,Cr(VI)离子的光催化还原过程都遵循L-H动力学规律,虽然加入CA和FN后,降低了吸附对光催化还原Cr(VI)的影响,但是Cr(VI)吸附至催化剂表面仍然是整个反应过程的关键.Using calcined sulfate-modified titanium-bearing blast furnace slag （STBBFS） as photocatalyst, the photocatalytic activity of STBBFS photocatalyst toward a Cr（VI）-citric acid [Cr（VI）-CA] system and a Cr（VI）-citric acid-ferric nitrate [Cr（VI）-CA-FN] system was studied. The results indicate that the photocatalytic activity of STBBFS photocatalyst is more efficiently enhanced in the Cr（VI）-CA-FN compound system than in the single Cr（VI） or Cr（VI）-CA system, indicating that the photocatalytic activity of STBBFS photocatalyst can be improved in the presence of citric acid and ferric nitrate. The acidic solutions are favorable for the photocatalytic reduction of Cr（VI）, and the optimum pH for the photocatalytic reduction of Cr（VI） is 2.5 in both compound systems. For the Cr（VI）-CA system, Cr（VI） is completely reduced after 50 min reaction when the photocatalytic activity of STBBFS photocatalyst is 0.426 mg·min^-1·g^-1. As for the Cr（VI）-CA-FN system, Cr（VI） is completely reduced after 16 min reaction when the photocatalytic activity of STBBFS photocatalyst is 1.2425 mg·min^-1·g^-1. Both the photocatalytic reductions of Cr（VI） in the Cr（VI）-CA system and Cr（VI）-CA-FN system follow a Langmuir-Hinshelwood kinetic model. Though the effect of adsorption on the photocatalytic reduction of Cr（VI） was decreased, the adsorption of Cr（VI） on the catalyst surface still affected the photocatalytic activity of STBBFS photocatalyst remarkably.

关 键 词：硫酸盐掺杂的含钛高炉渣 Cr(VI)-柠檬酸复合体系 Cr(VI)-柠檬酸-硝酸铁复合体系 光催化活性 CR(VI) 

分 类 号：TQ426[化学工程]