方形花状Bi_2WO_6可见光催化降解制革废水  

Photocatalytic Degradation of Tannery Wastewater by Square Flower-like Bi_2WO_6 under Visible Light

作　　者：陈渊[1,2,3] 杨家添[1,2,3] 韦庆敏[1,2,3] 晏全[1,2,3] 黎中良[1,2,3] 秦颖瑜 

机构地区：[1]玉林师范学院广西农产资源化学与深度利用重点实验室(培育基地),广西玉林537000 [2]玉林师范学院广西高校桂东南特色农产资源高效利用重点实验室,广西玉林537000 [3]玉林师范学院化学与食品科学学院,广西玉林537000

出　　处：《广西师范大学学报（自然科学版）》2016年第4期60-69,共10页Journal of Guangxi Normal University:Natural Science Edition

基　　金：广西科学研究与技术开发计划项目(桂科攻1598007-1);广西教育厅科研项目(KY2015ZD097;LX2014295);广西理工科学实验中心开放课题(LGZXKF201111);玉林师范学院教授科研启动基金(G20140006);全国大学生创新创业训练计划项目(201510606021;201610606008)

摘　　要：以Bi(NO_3)_3·5H_2O和Na_2WO_3·2H_2O为原料,EDTA为络合剂,辅助水热法合成Bi_2WO_6光催化剂,采用X射线衍射(XRD)、扫描电镜(SEM)、拉曼光谱(Raman)、紫外—可见漫反射光谱(DRS)等测试手段对产品进行表征。同时,在Bi_2WO_6光催化降解制革废水反应中考察了催化剂投加量、空气通入量、溶液pH值、双氧水用量及光照强度对制革废水COD_(cr)去除率的影响。结果表明,Bi_2WO_6光催化剂的结晶度良好,具有Bi_2WO_6特征峰,为规则方形花状Bi_2WO_6,其带隙能为2.696eV。Bi_2WO_6能有效降解制革废水中的有机物质,废水的COD_(cr)去除率显著提高。通过正交实验确定了降解制革废水最佳工艺条件为:Bi_2WO_6光催化剂的投加量为2.0g/L,自然pH值,体积分数2%H_2O_2,空气通入量为中档,灯液光照距离为11cm,可见光照射3.0h。该条件下,制革废水的脱色率和COD_(cr)去除率分别达到91.5%和92.6%,达到了国家相关排放标准。Bi_2WO_6晶体的可见光催化降解制革废水过程符合一级反应速率动力学方程。Using Bi（NO3）3 ·5H2O and Na2WO3 ·2H2O as raw materials,Bi2WO6 was successfully synthesized by hydrothermal method with ethylenediamine tetraacetic acid（EDTA）as the chelating agent.The properties of the as-prepared samples were investigated by XRD,SEM,Raman and UV-vis DRS tests.The as-prepared products were used to photodegrade tannery wastewater.The effects of dosage of Bi2WO6 photocatalyst,air flow rate,pH of wastewater,H2O2 dosage and the illumination intensity on the wastewater degradation were investigated in detail.The results showed that highly crystallinity square flower-like Bi2WO6 with its band gap of 2.696 eV could be obtained via a hydrothermal route assisted by EDTA.The Bi2WO6 could effectively degrade the hardly-degraded organic pollutants,and the COD（cr）removal rate increased significantly.The optimum conditions of treatment of tannery wastewater were natural pH value,Bi2WO6 of 2g/L,H2O2 of 2%,amount of air of mid-range,distance of light liquid light of 11 cm,reaction time of 3.0 h.Under the optimal conditions,the decolorization rate and COD（cr）removal rate were 91.5% and 92.6%.The dynamic behavior of Bi2WO6 photocatalyst degrading the molasses fermentation wastewater agrees with the firstorder rate dynamic equation.

关 键 词：Bi2WO6 水热法 制革废水 脱色率 CODCR去除率 

分 类 号：TQ032.4[化学工程] X703.1[环境科学与工程—环境工程]