摘要
研究了通过溶胶-凝胶共混法制备g-C_(3)N_(4)/介孔TiO_(2)复合催化剂,并用于光催化还原Cr(Ⅵ),分析了g-C_(3)N_(4)/介孔TiO_(2)光催化还原性能及稳定性。结果表明:g-C_(3)N_(4)与介孔TiO_(2)最佳掺杂比为1∶5,g-C_(3)N_(4)/介孔TiO_(2)比表面积为137.061 m^(2)/g;吸收边界红移至可见光区域,禁带宽度为2.64 eV;g-C_(3)N_(4)/介孔TiO_(2)在Cr(Ⅵ)初始质量浓度1 mg/L、溶液pH=5、催化剂投加量1.6 g/L、未添加无机离子条件下反应45 min,光催化还原率高达100%;可见光照射下,g-C_(3)N_(4)/介孔TiO_(2)产生的光生电子可将吸附在催化剂表面上的Cr(Ⅵ)还原成Cr(Ⅲ),反应更符合准一级反应动力学模型;催化剂循环使用7次后,对废水中Cr(Ⅵ)的去除率仍保持在83%以上,具有潜在应用价值。
The preparation of g-C_(3)N_(4)/mesoporous TiO_(2)composite catalyst by sol-gel blending method was studied and used in photocatalytic reduction of Cr(Ⅵ).The photocatalytic reduction performance and stability of g-C_(3)N_(4)/mesoporous TiO_(2)were analyzed.The results show that the optimal doping ratio of g-C_(3)N_(4)to mesoporous TiO_(2)is 1∶5,and the specific surface area of g-C_(3)N_(4)/mesoporous TiO_(2)is 137.061 m^(2)/g.The absorption boundary redshifts to the visible region,and the band-gap width is 2.64 eV.The photocatalytic reduction rate of g-C_(3)N_(4)/mesoporous TiO_(2)is up to 100%under the conditions of initial Cr(Ⅵ)mass concentration of 1 mg/L,solution pH=5,catalyst dosage of 1.6 g/L and no inorganic ions added for 45 min.Under visible light irradiation,g-C_(3)N_(4)/mesoporous TiO_(2)can produce photogenerated electrons,which can reduce Cr(Ⅵ)adsorbed on the surface of the catalyst to Cr(Ⅲ).The reduction reaction is in line with the first-order reaction kinetics model.The photocatalytic reduction rate of the catalyst remains above 83%after 7 cycles,and it has potential application value.
作者
汪益林
高博
张留科
徐浩
邢玉鲁
史焕鑫
赵宝秀
WANG Yilin;GAO Bo;ZHANG Liuke;XU Hao;XING Yulu;SHI Huanxin;ZHAO Baoxiu(School of Environmental and Municipal Engineering,Qingdao University of Technology,Qingdao 266000,China)
出处
《湿法冶金》
CAS
北大核心
2023年第3期282-290,共9页
Hydrometallurgy of China
