Fast and efficient removal of mercury from water samples using magnetic iron oxide nanoparticles modified with 2-mercaptobenzothiazole

► The removal time is short with respect to reported methods (4 min). ► Very low levels of Hg ions have been removed successfully from polluted water. ► The electrolyte concentration has not considerable effect on removal efficiency. ► Modified magnetic ironoxide nanoparticles improve efficiency up to 98.6%.