Fig. 4From: Environmentally benign Fe(III)–montmorillonite for rapid adsorption of methylene blue dye in aqueous medium under ambient conditionsRemoval of MB dye by a stoichiometric amount of Fe(III)–Mt at different pH. b Excess amount of Fe(III)–Mt at pH 3 and 7. c Sub-stoichiometric amount of Fe(III)–Mt at pH 3 and 7Back to article page