Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, 100084, PR China.
Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, 100084, PR China; Beijing Key Laboratory of Radioactive Waste Treatment, Tsinghua University, Beijing, 100084, PR China.
Environ Pollut. 2019 Jul;250:737-745. doi: 10.1016/j.envpol.2019.04.091. Epub 2019 Apr 23.
In this paper, the equilibrium and mass transfer kinetics of Sr sorption onto 3 types of microplastics, including polyethylene terephthalate (PET), polyethylene (PE), and polyvinyl chloride (PVC) were investigated. A novel film-pore mass transfer (FPMT) model was developed and used to study the sorption kinetics and mechanisms. This model can be used to describe the external mass transfer (EMT) and the internal mass transfer (IMT) processes and to calculate the diffusion rate. The FPMT model could successfully predict the kinetics data of Sr sorption onto microplastics. The maximum value of the EMT rate achieved at the beginning of sorption was 103 μg g·h for PET, 247 μg g·hfor PE, and 854 μg g·h for PVC, and then it decreased dramatically with time. The IMT rate was far less than the EMT rate, and decreased slowly with time. The overall sorption rate of Sr onto microplastics was controlled by the external mass transfer step.
本文研究了 3 种类型的微塑料（包括聚对苯二甲酸乙二醇酯（PET）、聚乙烯（PE）和聚氯乙烯（PVC））对 Sr 的吸附平衡和传质动力学。开发了一种新的膜孔传质（FPMT）模型来研究吸附动力学和机制。该模型可用于描述外部传质（EMT）和内部传质（IMT）过程，并计算扩散速率。FPMT 模型可以成功预测 Sr 吸附到微塑料上的动力学数据。在吸附开始时，EMT 速率的最大值为 PET 的 103μg g·h、PE 的 247μg g·h 和 PVC 的 854μg g·h，然后随时间急剧下降。IMT 速率远小于 EMT 速率，并随时间缓慢下降。Sr 整体吸附到微塑料上的速率由外部传质步骤控制。
