Removal of methylene blue in textile wastewater using bentonite and powdered activated carbon

Dye pollution contained in textile industry wastewater poses a serious danger in terms of damage to the environment. In this study, experiments were carried out on the removal of methylene blue dye from aqueous solution under ideal adsorption conditions using methylene blue dye used in the textile field. The effects of pH, temperature, mixing speed, dye concentration and adsorbent amount parameters on the adsorption process were examined. The highest dye removal efficiency was determined as 94.32% with bentonite and 99.73% with powdered activated carbon. Isotherm studies were carried out at different temperatures. Adsorption behavior was elucidated with the help of Langmuir, Freundlich and Temkin isotherm models, and isotherm constants. The maximum adsorption capacity was reached at 303.0303 mg/g with bentonite and 227.2727 mg/g with powdered activated carbon. Adsorption kinetics were determined by pseudo-first-order and pseudo-second-order kinetic models. Gibbs free energy, enthalpy and entropy change values were determined.