Environmental Nanoscience Laboratory, Department of Earth Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India.
Environmental Nanoscience Laboratory, Department of Earth Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India; Centre for Climate and Environmental Studies, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India.
Sci Total Environ. 2022 Apr 20;818:151831. doi: 10.1016/j.scitotenv.2021.151831. Epub 2021 Nov 21.
Despite the massive accumulation of nanoplastics (NPs) in the freshwater system, research so far has highly focused on the marine environment. NPs interaction with mineral surfaces can influence their fate in freshwater, which will further impact their bioavailability and transport to the oceans. Current work focuses on understanding NPs interaction with weathering sequence of minerals in freshwater under varying geochemical conditions. Primary mineral feldspar and weathering originated secondary minerals, i.e., kaolinite and gibbsite, were investigated for interaction with NPs under batch mode under relevant environmental conditions. Minerals-NPs interaction was also investigated in natural water samples. Results showed that the amorphous nature, small particle size, and positive surface charge of gibbsite resulted in multi-fold sorption of NPs (108.1 mg/g) compared to feldspar (7.7 mg/g) and kaolinite (11.9 mg/g). FTIR spectroscopy revealed hydrogen bonding and complexation as major players in gibbsite-NPs interaction suggesting the possibility of their co-precipitation. The continuous adsorption-desorption and limited sorption capacity of feldspar and kaolinite can be attributed to their negative surface charge, larger size, crystalline nature, and physical sorption. Therefore, both minerals may co-transport and enhance the mobility of NPs.
尽管纳米塑料（NPs）在淡水系统中大量积累，但迄今为止，研究主要集中在海洋环境上。NPs 与矿物表面的相互作用会影响它们在淡水中的命运，从而进一步影响它们的生物利用度和向海洋的迁移。目前的工作重点是了解 NPs 在不同地球化学条件下与淡水风化序列矿物的相互作用。研究了长石等原生矿物和风化形成的次生矿物，如高岭石和三水铝石，在相关环境条件下以批处理模式与 NPs 的相互作用。还研究了天然水样中的矿物-NPs 相互作用。结果表明，三水铝石的无定形性质、小颗粒尺寸和正表面电荷导致其对 NPs 的多倍吸附（108.1mg/g），而长石（7.7mg/g）和高岭石（11.9mg/g）则较少。傅里叶变换红外光谱揭示了氢键和络合是三水铝石-NPs 相互作用的主要因素，表明它们可能共沉淀。长石和高岭石的连续吸附-解吸和有限的吸附容量可归因于其负表面电荷、较大尺寸、结晶性质和物理吸附。因此，这两种矿物都可能共同迁移并增强 NPs 的迁移性。
