Adsorption Efficiency of Flamboyant Pods for Indigo Dye Removal from Textile Industrial Wastewater

Abstract

This study investigates flamboyant pods (FP) and chitosan [extracted from periwinkle shells (PS)] modified flamboyant pods (CMFP) adsorbents for dye removal from textile industrial wastewater, and were compared with commercial activated carbon (CAC). Physicochemical properties with dye concentrations of wastewater were investigated before and after adsorption using standard methods and Ultraviolet-visible Spectrophotometer respectively. Batch adsorption were performed and pH (3.0, 4.0, 6.0, 9.0, 11.5), adsorbent dosage (0.1, 0.2, 0.3, 0.4, 0.5 g), contact time (10, 20, 30, 40, 50, 60 minutes) and initial concentration (25, 50, 100, 125, 250 mg/L) were optimized for Indigo dye using the adsorbents. Initial concentration data was used to test conformity with Langmuir and Freundlich adsorption isotherms. Adsorption efficiencies for simulation ranged from 11.33±0.70 to 83.8±0.00. Optimum adsorption conditions of indigo dye were pH 6, 0.1g sorbent dosage, 60 minutes contact time and 250 mg/L dye concentration; gave efficiencies of 83.8%, 79.6% and 89.8% for FP, CMFP, CAC respectively with wastewater. Physicochemical parameters of wastewater decreased except nitrate which increased from 11.53±0.00 to 34.65±1.41mg/L. Data best fit Langmuir than Freundlich adsorption isotherm. The study inferred that FP and PS could be processed as less expensive, environment friendly alternative adsorbent to the costly CAC for treating textile wastewater.