Arsenic water decontamination by a bioinspired As-sequestering porous membrane

Abstract

Arsenic water contamination is a major issue worldwide, particularly in regions where groundwater is the primary source of drinking and irrigation water. Therefore, there is an urgent need of addressing this problem in an effective and environmentally friendly manner. So far, several conventional and emerging removal technologies have been implemented for arsenic removal from water, including coagulation, flocculation, adsorption and membrane-based separation approaches. Here we show the successful development of a new bio-inspired porous membrane that has been made selective for the removal of arsenic (As(V) as well as the more toxic and difficult to remove As(III)) present in arsenic-contaminated groundwaters. The arsenic removal efficiency of the membrane has been successfully assessed both in model solutions and in a real groundwater. Very importantly, owing to the high selectivity of the membrane towards arsenic, no substantial demineralization occurred with the real groundwater, which therefore became directly suitable for human consumption. Arsenic water contamination may affect spring water as well as water reservoirs around the world and requires the development of efficient and sustainable remediation technologies. A bioinspired porous membrane allows obtaining filtrated water with an As concentration below the recommendation from the World Health Organization.