A new approach to chromium concentration from salt mixture solution using nanofiltration

► Nanofiltration of model tannery solution was studied. ► The influence of the chlorides and sulfates concentration as well as Cl−/SO42- ratio was analyzed. ► The optimum Cl−/SO42- ratio in feed was below 1. ► Nanofiltration of chromium tannery wastewater with the recirculation of part of permeate was proposed.