Arsenic(V)removal from groundwater by GE-HL nanofiltration membrane:effects of arsenic concentration,pH,and co-existing ions

A laboratory-scale investigation was performed to study arsenic(As(V))removal by negatively charged GE-HL nanofiltration(NF)membrane in simulated drinking water.Effects of As(V)concentration(0–200μg·L–1),pH,and co-ions and counter-ions were investigated.The NF membrane presented good stability,and the rejection rates exceeded 90%.The rejection rates of As(V)decreased with the increase of As(V)concentration,while it increased with the increase of pH(reached 96%at pH 6.75).Moreover,a negative relationship was observed between the co-existing ions of Cl^(–),Na^(+),SO_(4)^(2–),and Ca^(2+)and the removal of As(V),in which bivalent ions presented more significant effects than monovalent ions.