Investigation of an optimized mineral adsorbent modified with polydopamine for the removal of methylene blue contaminants from industrial wastewater

Wastewater generated by the textile industry leads to significant color pollution and the release of hazardous substances. The adsorption process provides an effective method for mitigating organic pollutants, such as dye-laden wastewater. This study aimed to develop a Zeolite@Polydopamine composite that serves as a highly efficient material for the elimination of methylene blue dye from aqueous solutions. To attain maximum adsorption capacity, different effective parameters, such as temperature, contact time, dye concentration, adsorbent weight, and solution pH, were optimized. The optimal conditions for the removal process were established with a dye concentration of ۱۰ mg/mL and an adsorbent weight of ۳۰ mg. Under these conditions, the ideal contact time was achieved to be ۳۰ min, with a pH level of ۷ and a temperature maintained at ۲۵°C. Evaluations of isotherm models and adsorption kinetics revealed that the adsorption process is best defined by the pseudo-second-order kinetic model in conjunction with the Freundlich isotherm. Additionally, the maximum adsorption capacity, as calculated by the Langmuir model, was found to be ۷۰.۹۲ mg/g. The negative values observed for both enthalpy and entropy suggest that this process of adsorption becomes more desirable at lower temperatures.

کلیدواژه ها:

Adsorption isotherm ، Polydopamine ، Zeolite ، Methylene Blue ، synthetic adsorption