Adsorption Characteristics of Jackfruit Leaf Powder for the Removal of Amido Black 10B Dye

摘要

This work presents experimental studies on the adsorption characteristics (% dye removal and sorption capacity) of a low-cost adsorbent, jackfruit leaf powder (JLP), derived from agricultural waste (jackfruit leaves). The prepared JLP was used as adsorbent to study the effect of various parameters namely initial pH, adsorption time, temperature, agitation speed, JLP loading and initial dye concentration on dye removal efficiency. Then, the optimal process parameters for the dye-adsorbent system were determined. It has been observed that the dye removal efficiency increases with increasing the adsorbent dosage, adsorption time as well as stirrer speed and the optimal values of JLP dosage, adsorption time and stirrer speed were found to be 10 g/L, 5 h and 200 rpm, respectively. On the other hand, the dye removal efficiency decreased with increasing the initial dye concentration as well as temperature, indicating that the adsorption on JLP is exothermic and is effective at low concentrations of dye. The variation in dye removal efficiency with pH did not show any regular trend. A sudden drop in the removal efficiency from a pH of 6 to 8 was noticed. Maximum dye removal was obtained at low pH values (between 2 and 5) indicating the fact that the JLP surface is positively charged. JLP resulted in far better values of adsorption capacity (up to 3.7 mg/g) and dye removal efficiency (＞80%). Finally, the data were fitted to various equilibrium and kinetic models. Experimental data matched well with the pseudo-second-order kinetics and Freundlich isotherm models.