Luu Thi Trang, Truong Dai Quyet, Nguyen Van Nam, Jeong Sanghyun, Nguyen Thi Thu Trang, Do Van Manh, Vigneswaran Saravanamuthu, Nguyen Tien Vinh
Faculty of Engineering and IT, University of Technology Sydney (UTS), Sydney, NSW 2007, Australia.
Faculty of Urban Infrastructure and Environment Engineering, Hanoi Architectural University, Hanoi 100000, Vietnam.
Membranes (Basel). 2025 Feb 4;15(2):47. doi: 10.3390/membranes15020047.
Microplastic (MP) pollution has recently emerged as a critical global environmental issue. Laundry wastewater is a significant contributor to MP pollution, containing high concentrations of MPs. Although coagulation has recently been widely applied to remove MPs from such wastewater, its efficiency remains poor, and the removal mechanisms are not yet fully elucidated. In this study, the occurrence and characteristics of MPs in raw domestic laundry wastewater were investigated. The coagulation process was combined with ultrafiltration (UF) membrane filtration to enhance MP removal. The results showed that the concentrations of MPs in laundry wastewater ranged from 9000 to 11,000 particles/L, with fibrous particles constituting the majority (42.6%) and polyester accounting for 68.2% of detected MPs. Using aluminium chloride and ferric chloride as coagulants, maximum removal efficiencies of 91.7 and 98.3% were achieved, respectively. Mechanistic analysis revealed that charge neutralization played a dominant role during coagulation. Fourier transform infrared spectroscopy further demonstrated the formation of new functional groups, substituted benzene rings, and the presence of Fe-O and Al-O bonds, indicating the interaction between MPs and coagulants. Furthermore, the UF membrane was used to remove fibrous MPs and MPs with low densities. These MPs had not been removed with pre-coagulation. The removal efficiency of these MPs reached 96 ± 2%, reducing their concentration to only 60 particles/L in the UF permeate. These findings highlight the synergistic potential of coagulation and UF membrane filtration for effective MP removal and provide a valuable reference for advancing wastewater treatment technologies targeting MP pollution.
微塑料（MP）污染最近已成为一个关键的全球环境问题。洗衣废水是MP污染的一个重要来源，含有高浓度的微塑料。尽管最近混凝法已被广泛应用于去除此类废水中的微塑料，但其效率仍然很低，去除机制尚未完全阐明。在本研究中，调查了生活洗衣原废水中微塑料的存在情况和特征。将混凝过程与超滤（UF）膜过滤相结合以提高微塑料的去除率。结果表明，洗衣废水中微塑料的浓度范围为9000至11000个颗粒/升，纤维状颗粒占大多数（42.6%），聚酯占检测到的微塑料的68.2%。使用氯化铝和氯化铁作为混凝剂，最大去除效率分别达到91.7%和98.3%。机理分析表明，电荷中和在混凝过程中起主导作用。傅里叶变换红外光谱进一步证明了新官能团、取代苯环的形成以及Fe-O和Al-O键的存在，表明微塑料与混凝剂之间存在相互作用。此外，超滤膜用于去除纤维状微塑料和低密度微塑料。这些微塑料在预混凝过程中未被去除。这些微塑料的去除效率达到96±2%，使超滤渗透液中的浓度仅降至60个颗粒/升。这些发现突出了混凝和超滤膜过滤在有效去除微塑料方面的协同潜力，并为推进针对微塑料污染的废水处理技术提供了有价值的参考。
