Adsorption of Methylene blue on pretreated rice husk by using acidic deep eutectic solvent

Abstract

Methylene blue is mainly used in textile industry where it was discharged as a constituent effluent into water bodies that can caused harm to the environment. Rice husk was found abundantly in Malaysia and are cheap. Thus, these studies were about using rice husk treated with acidic deep eutectic solvent (DES) which is a green solvent to adsorb methylene blue from the waste water in batch adsorption system. The acidic DES solvent used was mixture of choline chloride and oxalic acid. The adsorption efficiency between untreated rice husk and treated rice husk has been experimented and it shows that treated rice husk has better adsorption after experiment was conducted. Three sizes of treated rice husk (212μm, 300μm and 425μm) were experimented and it was found out that smaller size shows better adsorption. To study the effect of parameters on biosorption, two parameters were studied. First parameter was the effect of contact time (30 minutes, 60 minutes, 90 minutes, 120 minutes, 150 minutes and 180 minutes) of treated rice husk on the removal of methylene blue.