MOF-5@Ni衍生的ZnO@Ni_(3)ZnC_(0.7)/PMS体系用于有机物去除——对吸附降解过程的深入理解

MOF-5@Ni Derived ZnO@Ni_(3)ZnC_(0.7)/PMS System for Organic Matter Removal:A Thorough Understanding of the Adsorption-Degradation Process

基于过一硫酸盐的非均相催化活化技术在废水处理中越来越受到关注。因此,找到一种可持续、经济、有效的活性材料用于废水处理非常重要。本研究以金属有机框架材料(MOF)-5为前驱体,通过添加镍离子并随后煅烧制备了一种稳定、可循环利用的材料ZnO@Ni_(3)ZnC_(0.7),该材料表现出良好的吸附和催化性能。为了研究和优化实际应用条件,选择了罗丹明B(RhB)在水中的降解作为模型过程。研究表明,体系中有机物的去除涉及吸附和降解过程的耦合。基于此,提出了整个去除过程的机理。扫描电子显微镜、红外光谱分析和理论分析的结果证实,范德华力、静电吸引力和氢键影响吸附过程。电子顺磁共振分析、遮蔽实验和电化学测试证实,RhB的降解路径包括自由基和非自由基途径,表面羟基是关键的活性位点。对吸附底物的降解使活性位点得到再生。用简单方法再生的材料在四个循环测试中对有机化合物的去除效率保持很高。此外,这种材料还可以有效地去除各种有机污染物,并且由于具有磁性,材料易于回收。结果表明,使用具有良好吸附能力的非均相催化材料可能是一种经济有效的策略。

The heterogeneous catalytic activation of peroxymonosulfate(PMS)for wastewater treatment is attracting increased research interest.Therefore,it is essential to find a sustainable,economical,and effective activated material for wastewater treatment.In this study,metal–organic framework(MOF)-5 was used as the precursor,and a stable and recyclable material ZnO@Ni_(3)ZnC_(0.7)that exhibited good adsorption and catalytic properties,was obtained by the addition of nickel and subsequent calcination.To investigate and optimize the practical application conditions,the elimination of rhodamine B(RhB)in water was selected as the model process.This study demonstrated that the degradation of organic matter in the system involved a coupling of the adsorption and degradation processes.Based on this,the mechanism of the entire process was proposed.The results of scanning electron microscopy,infrared spectrum analysis,and theoretical analysis confirmed that the van der Waals forces,electrostatic attraction,and hydrogen bonding influenced the adsorption process.Electron paramagnetic resonance analysis,masking experiments,and electrochemical tests conducted during the oxidative degradation process confirmed that the degradation mechanism of RhB included both radical and non-free radical pathways,and that the surface hydroxyl group was the key active site.The degradation of the adsorbed substrates enabled the regeneration of the active sites.The material regenerated using a simple method exhibited good efficiency for the removal of organic compounds in four-cycle tests.Moreover,this material can effectively remove a variety of organic pollutants,and can be easily recovered owing to its magnetic properties.The results demonstrated that the use of heterogeneous catalytic materials with good adsorption capacity could be an economical and beneficial strategy.