Studies on removal of malachite green dye from aqueous solution using plant based biosorbents

Abstract

The removal of malachite green dye from wastewater is carried out using papaya wood, banana peel, and bael shell as biosorbents. Batch scale biosorption studies were carried out to evaluate the effect of various parameters such as time of contact, temperature, initial pH, biosorbate dosage and the suitable criteria for these factors were estimated. It was found that the effective time of contact for better dye removal performance was around 140 min at the dye concentration of 10 mg/l for all the three biosorbents. The removal efficiency of biosorbents was found maximum at pH 10 for papaya wood, at pH 7 for banana peel and at pH 8 for bael shell. Moreover, the optimum doses of these biosorbent materials were estimated at 0.06, 0.1 and 0.12 g/100 ml for papaya wood, banana peel and bael shell respectively. Maximum removal of dye was achieved at temperature 50°C for all the three biosorbents. Isotherm study of biosorption was done as well as the suitable fitting isothermal models were also demonstrated. Isotherm of Langmuir and Freundlich concepts were utilized to fit the equilibrated data and the outcomes showed that the Langmuir concept appeared better than Freundlich’s one. The results showed that papaya wood, banana peel and bael shell are proficient to use as an alternative for treating effluents which have malachite green in the water sample.