Onion Husk Powder as a Adsorbent for Removal of Methylene Blue and Malachite Green from Aqueous Solutions

Abstract

A large quantity of synthetic dyes used for textile, industrial operations and releases highly harmful colored liquid in the form of wastewater. The effluents which are released from textile industries are becomes harmful to human beings as well as environment. The effluent must be treated before discharge into environment. Conventional and non-conventional treatment processes are frequently used to treat effluents. In the present study, we report experimental work based on adsorption of synthetic dyes—methylene blue and malachite green using onion husk powder. Maximum dye uptake capacity of methylene blue is 75.34% occurred at a 20 ppm of MB dye concentration, early MB pH of 7.0, onion husk powder dosage of 1 g/50 mL, reaction temperature of 303 K and reaction time of 90 min. Similarly, maximum uptake capacity of malachite green is 62.97% occurred at a 20 mg/L of dye concentration, an initial pH of 4.0, temperature 303 K, 0.5 g/50 mL of sorbent dosage and contact time of 90 min. Without any treatment of onion husk powder used as a sorbent for adsorption of synthetic dyes- methylene blue and malachite green up to 75.34 and 62.97%.