RESUMEN
Growing concerns over poor air quality, especially in urban and industrial regions, have led to increased global demands for advanced air-purification technologies. However, the stability and airborne pollutant control abilities of the available air-purification materials under diverse environmental conditions are limited. Thus, the advanced development of filtration materials that can effectively control different types of pollutants, such as particulate matter (PM) and gaseous pollutants, simultaneously has attracted attention. The zeolitic imidazolate framework (ZIF), a type of porous metal-organic framework (MOF), is a promising material for capturing weakly acidic toxic gases such as SO2 owing to its excellent adsorption performance and high thermal and chemical stability. In this study, we successfully developed an ultrastable necklace-like multifunctional hybrid membrane via the cetyltrimethylammonium bromide-assisted in situ growth of zeolitic imidazolate framework (ZIF)-67 crystals on electrospun Co2+-doped poly(vinylidene fluoride) nanofibers (70 nm) that can be used in different moisture environments to achieve sustainable air-filtration performance. The hybrid nanocomposite membrane demonstrated excellent performance for the simultaneous control of intractable fine PM0.3 (filtration efficiency, 99.461%) and SO2 (adsorption capacity, 1476.5 mg g-1) under different humidity conditions. This study contributes to the optimal synergistic integration of the advanced metal-organic framework (MOF)-nanofiber nanocomposite membranes and can guide the rational design and conceptualization of a facile and novel membrane for various applications in the environmental science and energy fields.
RESUMEN
Plastic pollution has been a significant and widespread global issue, and the recent COVID-19 pandemic has been attributed to its worsening effect as plastics have been contaminated with the deadly infectious virus. Microplastics (MPs) may have played a role as a vector that carries hazardous microbes such as emerging bacterial threats (i.e. antibiotic resistant bacteria) and deadly viruses (e.g., coronavirus); this causes great concern over microplastics contaminated with emerging contaminants. Mitigation and treatment of MPs are challenging because of a range of factors including but not limited to physicochemical properties and composition of MPs and pH and salinity of the solution. Despite the heterogeneous nature of aquatic systems, research has overlooked interactions between contaminants and MPs under environmental conditions, degradation pathways of MPs with adsorbed contaminants, and, especially, the role of adsorbed contaminants in the efficiency of MP treatment through membrane filtration, in comparison with other treatment methods. This review aims to (1) analyze an assortment of factors that could influence the removal of MPs and mechanisms of contaminant adsorption on MPs, (2) identify mechanisms influencing membrane filtration of MPs, (3) examine the fate and transport of MPs with adsorbed contaminants, (4) evaluate membrane filtration of contaminant-adsorbing MPs in comparison to other treatment methods, and (5) draw conclusions and the future outlook based on a literature analysis.