Chen Chunzhao, Sun Chenxi, Wang Bin, Zhang Zhiguo, Yu Gang
Advanced Interdisciplinary Institute of Environment and Ecology, Beijing Normal University, Zhuhai, China.
School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, Beijing Laboratory of Environmental Frontier Technologies, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing, China.
Sci Total Environ. 2024 Jan 1;906:167430. doi: 10.1016/j.scitotenv.2023.167430. Epub 2023 Sep 29.
Nanoplastics (NPs) contribute substantially to the transport of waterborne pollutants. Triclosan (TCS) has a high potential to contact with NPs because of their prevalence in natural waters. Herein, this study investigated the adsorption behavior of TCS on differently sized and functionalized polystyrene (PS) NPs. The effects of environmental factors such as pH, salinity, and dissolved organic matter (DOM) were also evaluated. Results suggest that the adsorption equilibrium constant (k) of TCS in pristine PSNP suspensions followed the order as: PSNPs-50 nm (4.39 L·g) > PSNPs-100 nm (2.78 L·g) > PSNPs-200 nm (2.59 L·g) > PSNPs-500 nm (1.36 L·g) ≈ PSNPs-900 nm (1.36 L·g). For the functionalized PSNPs (i.e., PSNPs-COOH, PSNPs-NH), the values of specific surface area normalized k called k, were higher than those of pristine PSNPs. Meanwhile, TCS adsorption on two functionalized PSNPs remained stable and then decreased as salinity increased, while an opposite trend was observed toward pristine PSNPs. All these suggested that physicochemical properties of PSNPs (e.g., particle size and surface functional groups) are important factors influencing their adsorption capacity. When the solution pH raised, the adsorbed amounts of TCS on all tested PSNPs prone to decline. However, DOM only affected the adsorption behavior of PSNPs-50 nm, probably owing to its aggregation with tiny PSNPs and the induced secondary adsorption.
纳米塑料（NPs）在水传播污染物的传输中起着重要作用。三氯生（TCS）因其在天然水体中的广泛存在而极有可能与纳米塑料接触。在此，本研究调查了三氯生在不同尺寸和功能化的聚苯乙烯（PS）纳米塑料上的吸附行为。同时还评估了pH值、盐度和溶解有机物（DOM）等环境因素的影响。结果表明，在原始PSNP悬浮液中，三氯生的吸附平衡常数（k）遵循以下顺序：PSNPs - 50nm（4.39 L·g）> PSNPs - 100nm（2.78 L·g）> PSNPs - 200nm（2.59 L·g）> PSNPs - 500nm（1.36 L·g）≈ PSNPs - 900nm（1.36 L·g）。对于功能化的PSNPs（即PSNPs - COOH、PSNPs - NH），比表面积归一化后的k值（称为kₛ）高于原始PSNPs。同时，三氯生在两种功能化PSNPs上的吸附先保持稳定，然后随着盐度增加而降低，而原始PSNPs则呈现相反的趋势。所有这些表明，PSNPs的物理化学性质（如粒径和表面官能团）是影响其吸附能力的重要因素。当溶液pH值升高时，三氯生在所有测试PSNPs上的吸附量均趋于下降。然而，DOM仅影响PSNPs - 50nm的吸附行为，这可能是由于其与微小PSNPs的聚集以及由此引发的二次吸附。
