Keggin型铜取代磷钨杂多阴离子可见光催化降解罗丹明B

以Keggin型铜取代杂多阴离子PW11O39Cu(Ⅱ)(H2O)5-PW11Cu]为可见光催化剂，有机染料罗丹明B(RhB)为模型污染物，研究了在可见光照射下PW11Cu对RhB的可见光催化降解作用，提出了PW11Cu可见光催化作用的反应机理，同时考察了RhB初始浓度、PW11Cu初始浓度和溶液pH值对RhB光催化降解速率的影响。 实验结果表明，含有15.6 μmol/L PW11Cu+10 μmol/L RhB的水溶液在可见光照射下反应80 min，RhB的降解率达100%，总有机碳去除率约33%。 RhB的可见光催化降解服从准一级动力学方程，在RhB初始浓度为20、30和40 μmol/L的情况下，其表观一级速率常数分别为3.1×10-2、2.0×10-2和1.5×10-2 min-1。

Visible Photocatalytic Degradation of Rhodamine B Using Copper-Substituted Tungstophosphate Heteropolyanion

Using Keggin-type copper-substituted heteropolyanion PW11O39Cu(Ⅱ)(H2O)5-(PW11Cu) as a visible photocatalyst,and organic dye Rhodamine B(RhB) as a model pollutant,this work reports a study on the visible photocatalysis of PW11Cu towards RhB degradation in aqueous solution under visible light irradiation.A visible photocatalysis mechanism is proposed.At the same time,influences of the initial RhB concentration,the initial PW11Cu concentration and the solution pH on the degradation rate of RhB are also examined.Experimental results show that 100% of RhB degradation is reached at 80 min under visible light irradiation of a solution containing 15.6 μmol/L PW11Cu and 10 μmol/L RhB,and a total organic carbon removal is about 33%.The visible photocatalytic degradation of RhB follows the quasi-first order kinetic regime and the observed rate constant is estimated to be 3.1×10-2,2.0×10-2 and 1.5×10-2 min-1 corresponding to the initial RhB concentration of 20,30 and 40 μmol/L,respectively.