MOE Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, College of Chemistry, Fuzhou University, Fuzhou 350116, PR China; College of Environment and Safety Engineering, Fuzhou University, Fuzhou 350116, PR China.
MOE Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, College of Chemistry, Fuzhou University, Fuzhou 350116, PR China.
Sci Total Environ. 2022 May 15;821:153471. doi: 10.1016/j.scitotenv.2022.153471. Epub 2022 Jan 29.
As a kind of emerging pollutant, microplastics (MPs) play an important role as a carrier for pollutant migration in the water environment. Carried by the MPs, benzotriazoles, and benzothiazoles (collectively referred to as BTs) are ubiquitous water contaminants. In this paper, the adsorption behavior of BTs on polyvinyl chloride (PVC) MPs was first studied systematically to explain the adsorptive mechanisms and the consequential pollution caused by the absorption-desorption process. The studies on kinetics, isotherms, and thermodynamics revealed that the adsorption of BTs on PVC MPs was a multi-rate, heterogeneous multi-layer, and exothermic process, which was affected by external diffusion, intra-particle diffusion, and dynamic equilibrium. The factors including pH, salinity, and particle size also influenced the adsorption process. In the multi-solute system, competitive adsorption would occur between different BTs. The desorption of BTs from PVC MPs was positively associated with the increase of adsorption amount. Based on the results, the adsorption mechanisms of PVC MPs were clarified, involving hydrophobic interaction, electrostatic force, and non-covalent bonds. It was demonstrated that BTs in the water environment could most probably be accumulated and migrated through MPs, and eventually carried into organisms, posing an increased risk to the ecological environment.
作为一种新兴污染物，微塑料（MPs）在水环境中作为污染物迁移的载体起着重要作用。被 MPs 携带的苯并三唑（BTs）和苯并噻唑（统称为 BTs）是普遍存在的水污染物。在本文中，首次系统地研究了 BTs 在聚氯乙烯（PVC） MPs 上的吸附行为，以解释吸附机制以及吸收-解吸过程造成的污染。对动力学、等温线和热力学的研究表明，BTs 在 PVC MPs 上的吸附是一个多速率、非均相多层和放热的过程，受外部扩散、颗粒内扩散和动态平衡的影响。pH 值、盐度和粒径等因素也会影响吸附过程。在多溶质体系中，不同 BTs 之间会发生竞争吸附。BTs 从 PVC MPs 上的解吸与吸附量的增加呈正相关。基于这些结果，阐明了 PVC MPs 的吸附机制，包括疏水相互作用、静电力和非共价键。研究表明，水环境中的 BTs 很可能通过 MPs 被积累和迁移，并最终进入生物体，从而对生态环境构成更大的风险。
