Study of the Sorption Processes of Petroleum Products in Wastewater using Natural and Modified Bentonite

Bukhara State University, 200117, M. Ikbol str., 11, Bukhara, Uzbekistan.

^* Corresponding author: m.r.amonov@buxdu.uz

Abstract

This study investigates the sorption behaviour of petroleum products from wastewater using natural and modified bentonites. with comparative analysis against activated carbon. Sorption experiments were conducted under static and dynamic conditions using model and real wastewater samples with varying concentrations of petroleum contaminants. The kinetics of sorption revealed that the process reached equilibrium within 2.5-3 hours, and the maximum sorption capacity was directly proportional to pollutant concentration. Thermally, chemically, and thermochemically modified bentonites exhibited 1.5-3 times higher sorption efficiency compared to natural bentonite. Thermochemically modified bentonite demonstrated the highest sorption capacity (up to 5.67 mg/g). Thermal analysis confirmed structural stability up to 400°C. while IR spectroscopy indicated preservation of the mineral framework after modification. Additionally, the study evaluated the synergistic use of bentonite. kaolin, coagulants, and flocculants to improve wastewater treatment efficiency. Regression models describing the sorption dynamics were developed with high predictive accuracy (R2 > 90%). The results validate the suitability of Navbahor bentonite. particularly in modified forms, as a cost-effective and efficient sorbent for oil-contaminated wastewater treatment.