Development and evaluation of woven fabric microfiltration membranes impregnated with silver nanoparticles for potable water treatment

Abstract

Access to clean and safe drinking water is a fundamental human need, which is commonly lacking in remote rural areas. A simple gravity-fed water treatment unit was developed based on woven fabric microfiltration (WFMF) membranes. However, since these membranes are loose micro-filters, the unit has to be used in conjunction with a disinfectant. This paper explores combining the WFMF membranes with silver nanoparticles (AgNPs) using a modified chemical reduction method. The originally white membranes turned brown–yellow due to the surface plasmon resonance of silver; however, there was no significant difference in the morphology of the membranes after the impregnation with 0.0117 wt% AgNPs. The coated membranes were more hydrophilic and had higher water permeability (p<0.05). Filtration of turbid water (40–700 NTU) showed that both membranes produced clear permeate (<1 NTU). Treatment of water spiked with bacteria (2500–77,000 CFU/100 mL Escherichia coli) showed that the removal efficiency of uncoated membranes was 84–91% and that of coated membranes was 100%. Accordingly, the coated membranes depicted great potential for water treatment. To the best of our knowledge, this is the first study that investigated the incorporation of AgNPs in WFMF membranes and characterized their properties.