Green and Sustainable Water Purification Membranes

Current wastewater treatment technologies are not effective at removing many small molecules and ions that are deleterious to human health. The US Environmental Protection Agency (EPA) is focused on the removal of many classes of compounds from drinking water and from wastewater including; disinfection byproducts (DBP) precursors, pharmaceuticals, personal care products, heavy metals and per- and polyfluoroalkylated substances (PFAS) that have been detected in global drinking water resources. Hence, there is a need to fabricate purification systems that would target these specific hydrophilic molecules and deliver safe and purified drinking water. In order to achieve this, a green (all-Aqueous) nanoscale anion exchange resin will be developed. This will comprise of poly(vinylbenzyl trimethylammonium chloride) (poly(vbTMAC) functionalized cellulose nanofibers. These resins work on the hypothesis that they utilize the anionic character of majority of the contaminants to remove them through electrostatic interactions. This functionalized Cellulose NanoResin (or CNR) will utilize the anion exchange resin character of the polymer and specific high surface area of the scaffold, cellulose nanofibers which will allow rapid removal of contaminants. Hence, the water purification system will be effectively fast and have ability to regenerate. Since cellulose nanofibers are abundant and inexpensive, this proposal aims to provide affordable water purification solutions to rural communities like in Brunswick County where high concentration of PFAS were found in water systems. We will analyze PFAS and other hydrophilic compounds present at environmentally relevant concentrations in water samples and aim to achieve concentrations well below maximum contaminant levels established by US EPA upon filtration. Hence, we will formulate novel CNR materials which will lead to fast and sustainable water purification systems.