Development and evaluation of woven fabric microfiltration membranes impregnated with silver nanoparticles for potable water treatment
Journal of Membrane Science
Durban University of Technology, Department of Chemical Engineering, P.O. Box 1334, 4001, Steve Biko Rd, Durban, South Africa; Stellenbosch University, Department of Process Engineering, Banghoek Rd, Stellenbosch 7601, South Africa
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. © 2014 Elsevier B.V.