Analysis of Efficiency and TheAdsorptionNature ofMalachiteGreenDye fromanAqueous Solution on activatedCarbonGenerated fromStrychnos potatorum(Ingini) seeds

Abstract

Malachite green (MG) is a basic dye with an amino group which is water soluble. This is a higher brilliance dye even in low concentrations. Therefore, MG is used mainly in dyeing for wool, leather, cotton, paper, wood, jute and as an anti-bacterial, anti-fungal, and anti-parasitical agent in aquaculture. The releasing of wastewater with MG from various industries is a huge problem because of the existence of MG in the wastewater causes toxicity for aquatic lives and it enters into the trophic levels of the food chains and causes teratogenic, mutagenic, carcinogenic and tumor-enhancing effects on human beings. Therefore, the major concern of this study is the removal of MG dye from an aqueous solution on activated carbon generated from Strychnos potatorum (Ingini) seeds (ACSP). The ACSP was characterized by Scanning electron microscope (SEM). The batch adsorption studies were conducted to determine the effect of adsorbent dosage, initial MG concentration, contact time and temperature on the removal of MG. The efficiency of the dye adsorption was determined by Pseudo-first order and Pseudo-second order kinetic models. The adsorption nature was determined by the thermodynamic study. According to the results of this study, the maximum removal percentage of MG dye (99.67%) was obtained for 0.20 g of adsorbent per 25.00 mL of MG volume, pH 4, 30 0C, 60 mg L-1 of initial MG concentration and 2 h contact time and Pseudo-second order kinetic model was well fitted to the data. The negative value for the Gibbs free energy change showed the spontaneity and feasibility of this adsorption process.