Performance of low pressure nanofiltration membrane in forward osmosis using magnesium chloride as draw solute

•PES nanofiltration membrane and magnesium chloride draw solute is used in FO process for wastewater concentration.•Water flux 11.8 L m−2 h−1 with pure water feed at 55 °C and 7.58 L m−2 h−1 for industrial wastewater feed using 1 mol L−1 MgCl2 draw solution observed.•Reversible membrane fouling with >90 % water flux recovery by simple DI water wash.•Good quality permeate containing < 1000 mg.L−1 TDS generated at ≤ 10 bar pressure using nanofiltration process.