Fe-Ce/g-C_(3)N_(4)芬顿催化剂的制备及其降解有机污染物性能研究

Preparation of Fenton catalyst Fe-Ce/g-C_(3)N_(4) and its performance for degradation of organic pollutants

通过一步热解铁基金属有机骨架材料(Fe-MOF)、铈基金属有机骨架材料(Ce-MOF)和三聚氰胺的混合物制备了一系列具有不同Fe/Ce质量比的Fe-Ce/g-C_(3)N_(4)。该材料在降解高浓度有机污染物时表现出优异的芬顿催化活性和稳定性。实验结果表明,Fe/Ce质量比对芬顿催化活性具有重要的影响,当Fe/Ce质量比为3∶1时催化剂表现出最优的活性,可在50 min内将亚甲基蓝(200 mg/L)全部移除。在反应体系中引入可见光,可进一步将反应时间缩短至40 min。该催化剂优异的芬顿反应性能归因于原位生成的g-C_(3)N_(4)作为载体有利于稳定和分散Fe和Ce离子;Fe和Ce之间的协同作用促进了Fe^(2+)的再生,从而高效产生羟基自由基氧化降解有机物。

A series of Fe-Ce/g-C_(3)N_(4) composites with different ratios of Fe/Ce are prepared by calcining the mixture of Fe-based metal organic framework(Fe-MOF),Ce-based metal organic framework(Ce-MOF)and melamine.The composite exhibits excellent Fenton catalytic activity and stability for degrading high concentration organic pollutants.It is shown via experiments that the ratio of Fe/Ce has important effect on Fenton reaction activity.The catalyst with a Fe/Ce ratio of 3∶1 shows the best catalytic activity,which can remove 100% of methylene blue(200 mg·L^(-1))within 50 min.If visible light is used in the reaction system,the reaction time will be further shortened to 40 min.The excellent Fenton reaction performance of the catalyst can be attributed to:(1)The in situ generated g-C_(3)N_(4) as support can stabilize well and disperse Fe and Ce cations;(2)The synergistic effect between Fe and Ce promotes the regeneration of Fe^(2+),leading to the production of more hydroxyl radicals to degrade organic pollutants.