微塑料对高铁酸盐氧化降解罗丹明B的影响

The Influence of Microplastics on the Oxidative Degradation of Rhodamine B by Ferrate

目的 研究微塑料对高铁酸盐降解有机污染物的影响,以罗丹明B作为模拟污染物,分别研究了微塑料添加量、高铁酸盐使用量、罗丹明B初始浓度、pH、天然有机物、无机离子等因素,对微塑料在反应过程中的影响。方法 通过改变氧化体系的反应条件,研究反应体系中添加微塑料、不添加微塑料以及仅有微塑料存在的情况下,分析高铁酸盐对罗丹明B的去除率,探究微塑料在氧化反应体系中的作用原理。结果 微塑料参与了高铁酸盐降解罗丹明B的氧化反应,反应后微塑料的形貌发生了改变,由最开始的光滑无空隙变为粗糙呈明显蜂窝状,且表面吸附有高铁酸盐的氧化产物。在不同反应条件下,微塑料对高铁酸盐氧化降解罗丹明B都具有促进作用,且促进作用不仅表现为对罗丹明B的吸附作用,其中的机理有待探究。微塑料在反应体系中的作用效果受污染物底物浓度影响较大。结论 微塑料存在的反应体系罗丹明B的去除率高于没有微塑料存在的反应体系,说明微塑料可以促进高铁酸盐氧化降解罗丹明B,提高罗丹明B的去除率。初步探究了微塑料在氧化体系中的作用影响,期望为实际污水处理中微塑料的去除治理的进一步研究提供理论支撑。

Objective This study investigated the influence of microplastics on the degradation of organic pollutants by ferrate.Rhodamine B was used as a simulated pollutant,and factors such as microplastic dosage,ferrate dosage,initial concentration of Rhodamine B,pH,natural organic matter,and inorganic ions were studied to explore the impact of microplastics in the reaction process.Methods By altering the reaction conditions of the oxidation system,the removal efficiency of Rhodamine B by ferrate was analyzed under different scenarios:with the addition of microplastics,without the addition of microplastics,and with the presence of microplastics only.The role of microplastics in the oxidation system was investigated.Results Microplastics participated in the oxidative degradation of Rhodamine B by ferrate,causing changes in the morphology of microplastics after the reaction.Initially smooth and devoid of any voids,the microplastics became rough and exhibited a distinct honeycomb structure,with adsorbed oxidized products of ferrate on their surface.Under different reaction conditions,microplastics had a promoting effect on the oxidative degradation of Rhodamine B by ferrate,not only through adsorption of Rhodamine B but also through other mechanisms that need to be explored.The effect of microplastics in the reaction system was greatly influenced by the concentration of the pollutant substrate.Conclusion The removal rate of rhodamine B in the reaction system with the presence of microplastics is higher than that in the reaction system without the presence of microplastics.This indicates that microplastics can enhance the oxidative degradation of Rhodamine B by ferrate and increase the removal rate of Rhodamine B.This study provides a preliminary exploration of the role and impact of microplastics in oxidative systems,offering theoretical support for further research on the removal and treatment of microplastics in practical wastewater treatment.