Utilizing Recycled Bentonite Clay Waste as a Novel Adsorbent for the Separation of Emulsified Engine Oil from Aqueous Solutions

This study involves employing thermally remediated bentonite clay waste as a novel, green, cost-effective, and environmentally friendly adsorbent to remove emulsified engine oil. The adsorbent material originates from factories that recycle spent engine oil as a waste by-product. Adsorption investigations were conducted in both batch and continuous systems. Five parameters were examined under batch conditions: contact time, temperature, pH, adsorbent dose, and initial concentration of the adsorbate. The batch experimental data were analyzed using isotherm, kinetic, and thermodynamic models. In the continuous system, three parameters were considered: influent adsorbate concentration, flow rate, and weight of the adsorbent (bed depth), followed by modeling using the Yoon–Nelson, Thomas, Adams–Bohart, and bed depth service time (BDST) models. The batch experimental data were found to be compatible with the Freundlich isotherm model and the Pseudo-Second-Order and Elovich kinetic models, with a maximum adsorption capacity of ۱۴۰.۸ mg/g. Moreover, the continuous adsorption data were consistent with the Thomas and BDST models, showing an ultimate adsorption capacity of ۲۶۳ mg/g. The economic feasibility of the prepared adsorbent is attributed to its availability and the necessary remediation potential for protecting environmental components. The characteristics of the adsorption process for this adsorbent are favorable, endothermic, and promising based on the modeling analysis.

کلیدواژه ها:

Adsorption ، Clay ، Oil ، Industrial Waste