Microplastics in the Environment: A Review Linking Pathways to Sustainable Separation Techniques

Since the mid-20th century, the quantity of microplastics (MPs) has increased significantly, becoming a persistent environmental pollutant widely distributed in global water bodies, soils, and the atmosphere. While plastic materials have brought significant convenience to daily life, the MPs resulting from their degradation pose increasing threats to ecosystems and human health. This comprehensive review examines the sources, migration pathways, and ecological impacts of MPs, and critically evaluates the current separation techniques from physical, chemical, and biological perspectives. In particular, numerical simulations of the hydrocyclone separation technique reveal its unique flow characteristics, including turbulent velocity gradients and axial pressure differences, with a separation efficiency of up to 93%. This technique offers advantages such as high efficiency, low energy consumption, and environmental friendliness. In response to the growing microplastic pollution issue, this review emphasizes that the development of future microplastic separation techniques should prioritize separation efficiency, sustainability, and environmental compatibility. Continued research in this field will provide theoretical support for optimizing microplastic pollution control technologies and contribute to achieving environmental protection and sustainable development goals.