微塑料吸附机制研究进展

Sorption behavior,mechanisms,and models of organic pollutants and metals on microplastics:A review

微塑料(MPs)广泛存在于土壤和水体环境中,可以充当载体影响污染物的二次释放和生物毒性,对生态环境造成巨大威胁。了解MPs的吸附机制有助于明确MPs对污染物的富集能力和潜在环境风险。本研究总结了MPs与亲水、疏水和重金属污染物之间相互作用机制,探讨了MPs性质、老化过程及环境因素对MPs吸附行为的影响,剖析了现阶段吸附模型及预测模型的发展现状,并针对现阶段研究的不足和未来的研究方向提出展望。本研究认为,MPs与污染物的相互作用机制主要包括疏水、静电、π-π和氢键相互作用;污染物和MPs性质、老化作用和环境因素会影响MPs的吸附行为;混合阶动力学模型、现象动力学模型以及预测模型的发展有助于明晰和快速预测MPs的吸附机制;今后的研究应更加关注复合污染物与MPs的相互作用机制、老化对MPs吸附的影响机制以及MPs吸附和预测模型的应用和开发。

Microplastics(MPs)are widely distributed in different environmental media and have raised extensive attention as good vectors for pollutants.MPs can either act as secondary sources of adsorbed pollutants to ambient environment or pose joint biological toxicity with carried contaminants.Investigations on sorption behavior and mechanisms of contaminants to MPs help to clarify MPs ability to enrich pollutants and their potential environmental risks.In this study,the interaction mechanisms between MPs and hydrophilic organic contaminants,hydrophobic organic contaminants and heavy metals were summarized.Besides,the effects of MPs properties,aging process and environmental factors on the adsorption behavior of MPs were discussed.Moreover,the development status of the current adsorption and prediction models were analyzed.Last but not least,future research directions were put forward based on the shortcomings of the current researches.The sorption mechanisms between MPs and pollutants mainly include hydrophobic,electrostatic,π-πand hydrogen bond interactions.The properties of MPs and pollutants,aging and environmental factors will affect the adsorption behavior of MPs.The development of mixed-order kinetics model,phenomenological kinetics model and predictive models is helpful to clarify and quickly predict the adsorption mechanism of MPs.Further efforts should be put into the interactions between combined pollutants and combined MPs,the effects of aging on MPs adsorption behaviors,and the application and development of relevant models.