Designing, fabricating, and testing of portable electrospun nanofilter systems for domestic water purification

Abstract

Membrane technology has been playing a vital role in water filtration and purification. Various technologies such as sand filtration, reverse osmosis, treatment with chemical disinfectants, and distillation have been used in the past for clean water sources. Membrane technology is a relatively easy method with many important features, including low operational temperature, low power consumption, and free of chemical additives. Membrane filtration can be further improved by using nanofibrous media in portable forms for drinking water supplies. Electrospun nanofibers possess high porosities, high surface area, good permeability and flexibility, unidirectional orientation, and well-connected pore structures, and therefore, an ideal candidate for portable water filtration purposes. Electrospinning is a novel method of fabricating nanofibers in various forms. In this study, nanofibrous membranes were fabricated using two polymers (polyacrylonitrile - PAN and polyethylene glycol -PEG), one solvent (dimethylformamide - DMF), and activated charcoal at different electrospinning conditions (DC voltages, pump speeds, and collector distances). Different water samples from the local pond, water jet cutter water, tap water, deionized (DI) water, and carbon black (CB) deionized water were used in this study. The water samples were tested for turbidity, total dissolved solids (TDS), electrical conductivity (EC), pH, and refractive index. The test results indicated that the proposed portable nanofilter system substantially improved the quality of the water sources for drinking and other household use. It is concluded that these nanofibrous membranes can easily purify contaminated water by eliminating impurities, such as organic and inorganic particles, viruses, bacteria, algae, and other pathogens.