Removal of arsenic and pesticides from drinking water by nanofiltration membranes

The prevailing mechanism of ion retention by the negatively charged nanofiltration membranes is the charge exclusion. The size exclusion mechanism is also important but not sufficient for the uncharged organic molecules rejection. The membrane material and the membrane pore size distribution (PSD) also influence the uncharged organic molecules rejections. The rejections of pesticides are reasonably high, and besides the size effect, the specific physicochemical phenomena should be considered in order to understand their rejection by the nanofiltration membranes.