CoAl-LDH/Bi_(2)MoO_(6)光催化-芬顿工艺高效降解罗丹明B

Efficient Degradation of Rhodamine B by CoAl-LDH/Bi_(2)MoO_(6)through Photocatalysis-Fenton Process

文中通过水热法成功制备了CoAl-LDH/Bi_(2)MoO_(6)复合光催化剂,并研究了其对工业废水中罗丹明B的去除性能,利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、傅里叶红外显微成像光谱仪(FTIR)、X射线光电子能谱仪(XPS)等对CoAl-LDH/Bi_(2)MoO_(6)催化剂进行一系列表征,考察了不同的pH、掺杂量、H_(2)O_(2)浓度、催化剂投加量对RhB降解效率的影响。试验结果表明,在pH值=6、H_(2)O_(2)物质的量浓度为10 mmol/L、投加量为0.6 g/L的条件下,质量比为1∶5的CoAl-LDH/Bi_(2)MoO_(6)表现出最优异的光催化芬顿活性,在60 min内对质量浓度为10 mg/L的RhB去除率达到97.8%,比单独的光催化体系和非均相芬顿体系的去除率均有提高,且循环后仍能保持较高的催化性能。这说明光催化与芬顿技术之间存在协同效应,CoAl-LDH/Bi_(2)MoO_(6)异质结促进了类芬顿反应中Co^(2+)、Co^(3+)的循环,同时提高了光生电子与空穴的分离和传输效率。

In this experiment,CoAl-LDH/Bi_(2)MoO_(6)composite photocatalysis catalyst was successfully prepared by hydrothermal method and the removal performance of rhodamine B(RhB)in industrial wastewater was studied.A series of characterization of CoAl-LDH/Bi_(2)MoO_(6)catalyst was carried out by XRD,SEM,FT-IR,XPS,and the effects of different pH value,doping amount,H_(2)O_(2)concentration,and catalyst dosage on RhB degradation efficiency were investigated.The experimental results showed that,under the conditions of pH value=6,H_(2)O_(2)concentration of 10 mmol/L,and dosage of 0.6 g/L,CoAl-LDH/Bi_(2)MoO_(6)with a mass ratio of 1∶5 showed the best photocatalytic-Fenton activity,and the removal rate of RhB with a concentration of 10 mg/L reached 97.8%in 60 min,which was higher than that of the single photocatalytic system and the heterogeneous Fenton system,and still maintained a high catalytic performance after cycling.This showed that there was a synergistic effect between photocatalysis and Fenton technology.CoAl-LDH/Bi_(2)MoO_(6)heterojunction promoted the cycle of Co^(2+)and Co^(3+)in Fenton reaction,at the same time,the separation and transmission efficiency of photogenerated electrons and holes was improved.