Sustainable Dye Removal Using Agricultural Waste: Green Synthesis of Chitosan-Immobilized Peanut Shells for AR1 Biosorption

This study delves into the exploration of novel, environmentally friendly, and economically viable chemically modified biosorbents from chitosan-immobilized peanut shells (CIPS). The aim is to efficiently remove acid red 1 dye (AR1) from wastewater. The produced biosorbents were thoroughly characterized analytically. To optimize the operating parameters, optimum conditions were determined by adsorption experiments carried out in batch and continuous systems. The study also monitored biosorption kinetics and evaluated equilibrium biosorption data with Langmuir, Freundlich, and Dubinin Radushkevich isotherm models. The biosorption potential of the developed material in a natural wastewater environment was tested. Possible biosorbent dye interactions were examined by SEM analysis. The initial pH, amount of biosorbent, initial dye concentration, foreign ion, and temperature effects of biosorption were examined in the batch system. Solution flow rate, amount of biosorbent, and desorption parameters were investigated in the continuous system. Maximum dye removal occurred at pH 2.0. The 0.2 g L-1 biosorbent achieved 84.5% AR1 dye removal. Among the applied kinetic models, the pseudo-second-order kinetic model is the one that best explains the biosorption kinetics. AR1 biosorption by immobilized biomass appears compatible with the Langmuir isotherm model. Studies carried out in a continuous system achieved 91.5% biosorption efficiency with 0.2 g L-1 biosorbent at pH 2.0. Experiments conducted to find the most suitable biosorption conditions show that biosorption depends on the initial pH, amount of biosorbent, and contact time. The biosorbent prepared in biosorption studies using real wastewater can be evaluated as a green potential candidate material for commercial-scale dye removal applications in industrial wastewater. This solution, utilizing peanut shell, an agricultural waste prepared with green synthesis, effectively removes AK1 dye due to its environmentally friendly and sustainable properties. Thus, a solution providing both economic and environmental advantages has been presented, offering reassurance in its potential.