Adsorption study of As(III)from water by iron-oxide-coated-manganese sand

The iron-oxide-coated-manganese sand is prepared.The paper takes this sand as adsorbent to study its adsorption of As(Ⅲ),pH and the adsorption kinetics and the regeneration tests are studied.The results show that the iron-oxide-coated-manganese sand can absorb As(Ⅲ)over a wide pH from 5.3to 8.4,the adsorption isotherm can be well described with the Langmuir adsorption model and the maximum static adsorption capacity is 20.61μg/ g,adsorption kinetics fits Lagergren second order kinetics equation,NaOH can better regenerate the iron-oxide-coated-manganese sand.At the same time,iron-oxide-coated-manganese adsorb As(Ⅲ)adsorption mechanism is discussed,and iron-oxide-coated-manganese sand on the As(Ⅲ)adsorption may be electrostatic non-specific adsorption and specific adsorption complexation result of the interaction.