类石墨相C_3N_4可见光催化还原Cr(Ⅵ)废水的研究  

Visible-light Photocatalytic Reduction of Cr(Ⅵ) Wastewater Using Graphite-like Carbon Nitride

作　　者：李瑞桢[1] 徐秋鹏[1,2] 汪虹西 邹落梅 李红菲[1] 廖宇琴 王万涛[1] 袁基刚[1] 王成端[1,3] 

机构地区：[1]四川理工学院化学与环境工程学院,四川自贡643000 [2]四川理工学院化学工程学院,四川自贡643000 [3]四川文理学院化学化工学院,四川达州635000

出　　处：《中国给水排水》2017年第5期89-93,共5页China Water & Wastewater

基　　金：国家自然科学青年基金资助项目(61601313);四川省教育厅重点项目(16ZA0261);四川理工学院人才引进项目(2015RC02);国家级大学生创新创业训练计划项目(201610622032);过程装备与控制工程四川省高校重点实验室项目(GK201611)

摘　　要：采用一步煅烧法制备了具有良好可见光催化活性的类石墨相氮化碳(g-C_3N_4)催化剂,并通过X射线衍射仪、扫描电子显微镜和傅里叶红外光谱对g-C_3N_4催化剂的晶体结构、表面形貌和分子结构等特性进行了表征。结果表明,该g-C_3N_4催化剂具有类石墨相晶型、良好的分散性和吸附性能,结合可见光可用于催化还原Cr(Ⅵ)废水。在Cr(Ⅵ)废水的体积为50 m L、空穴消耗剂(甲酸)的浓度为0.78 mol/L、g-C_3N_4催化剂的质量为80 mg、Cr(Ⅵ)废水的初始浓度(以K_2Cr_2O_7计)为50 mg/L条件下,35 min内对Cr(Ⅵ)的可见光催化还原效率达96.85%,并分析了g-C_3N_4催化剂对Cr(Ⅵ)的光催化还原机理。One-step calcination method was used to synthesize graphite-like carbon nitride （g- C3N4 ） with good visible-light photoeatalytic activity. The properties including the crystalline structure, the surface morphology, and the molecule structure of g-C3N4 were characterized using X-ray diffractome- ter （XRD） , scanning electron microscope （SEM） and Fourier transform-infrared spectroscopy （FT-IR）. The results indicated that the one-step calcination method had successfully synthesized g-C3 N, with good dispersity and adsorptivity. Visible-light photocatalytic reduction of Cr（ VI ） wastewater using g-C3N4 as photocatalyst was investigated, as well as the factors of the photoeatalytic reduction process. The reduc- tion efficiency of Cr（VI） reached up to 96.85% within 35 rain in a test where the volume of Cr（ VI ）wastewater solution was 50 mL, the concentration of formic acid as holes scavenger was 0.78 tooL/L, the mass of g-C3N4 was 80 mg, and the initial concentration of Cr（VI） in wastewater （ calculated as the con- centration of potassium dichromate） was 50 mg/L. In the end, the photocatalytic reduction mechanism of Cr（kI） on the surface of g-C3N4 catalyst was discussed.

关 键 词：类石墨相C3N4 可见光 光催化还原 Cr(VI)废水 

分 类 号：X703[环境科学与工程—环境工程]