Z型异质结C3N4/WO_(3)光催化还原处理含Cr (Ⅵ)废水的研究  

Study on photocatalytic reduction of Cr(Ⅵ)-containing wastewater by Z-type heterojunction C_(3)N_(4)/WO_(3)

作　　者：许荣杰 吴潘[1] 何坚[1] 刘长军[1] 蒋炜[1] XU Rong-jie;WU Pan;HE Jian;LIU Chang-jun;JIANG Wei(School of Chemical Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学化学工程学院,四川成都610065

出　　处：《现代化工》2022年第5期114-120,共7页Modern Chemical Industry

基　　金：国家自然科学基金(21978181和21676168)。

摘　　要：光催化技术处理含铬废水存在降解速率慢、外加有机牺牲剂等问题,限制了其实用化。设计构建了Z型异质结光催化剂C_(3)N_(4)/WO_(3)并用于处理含铬(Cr)废水,Z型异质结结构保证了其在可见光驱动下的光生载流子的有效分离,同时兼具WO_(3)的强氧化性和g-C_(3)N_(4)的强还原性;利用水或牺牲剂消耗光生空穴,可有效提升其对Cr(Ⅵ)的光还原效率和速率。在以甲醇为牺牲剂时,光反应36 min内可将Cr(Ⅵ)完全去除。通过对pH和催化剂用量的优化,无牺牲剂的体系中光还原反应50 min即可达到98.37%的降解率。Photocatalytic reduction technology is an effective way to treat with Cr(Ⅵ)-containing wastewater,but it suffers the problems such as slow degradation and the addition of organic sacrifice agent,which limits its practical application.Therefore,C_(3)N_(4)/WO_(3) Z-type heterojunction is constructed to treat with Cr(Ⅵ)-containing wastewater.Z-type heterojunction structure promotes the separation of photoelectric charge and has strong redox capacity under visible light.The photogenerated holes can be consumed by sacrificial agent or water,and therefore the photodegradation efficiency of Cr(Ⅵ)is effectively improved.Cr(Ⅵ)can be completely removed within 36 min of photoreaction when methanol is used as sacrificial agent.Through optimizing the pH and the dosage of catalyst,the degradation rate of Cr(Ⅵ)can achieve 98.37%after 50 min of photoreduction in the system without sacrificial agent.

关 键 词：含Cr(Ⅵ)废水 Z型异质结 无牺牲剂 光催化还原 

分 类 号：TQ138.1[化学工程—无机化工]