MODELING OF DYNAMIC (COLUMN) ADSORPTION AND BREAKTHROUGH CURVES IN AN ORGANOBENTONITE BED

Abstract

This study investigates the dynamic adsorption of petroleum hydrocarbons in an organobentonite adsorption bed for the effective treatment of oil-contaminated water. Experimental investigations were carried out in a continuous-flow fixed-bed column system. The effects of key operational parameters, including bed height, volumetric flow rate, and initial pollutant concentration, on the breakthrough behavior and adsorption performance were comprehensively evaluated. Based on the experimental results, breakthrough curves were constructed and the mass-transfer characteristics of the adsorption process were analyzed. To describe the adsorption dynamics and predict column performance, the Thomas, Yoon–Nelson, Adams–Bohart, and BDST (Bed Depth Service Time) models were applied. These models enabled the determination of the dynamic adsorption capacity of organobentonite, service time of the adsorption bed, and optimal operating conditions of the fixed-bed system. The results demonstrated that increasing the bed height prolonged the breakthrough time and enhanced pollutant removal efficiency, whereas increasing the volumetric flow rate reduced the contact time between the adsorbate and adsorbent, resulting in lower adsorption performance. The maximum dynamic adsorption capacity of organobentonite was determined to be 57 mg/g. The optimal empty bed contact time (EBCT) was found to be 20 minutes, while the optimal filtration velocity was established at 5 m/h. The findings indicate that organobentonite is a promising adsorbent for the treatment of petroleum-contaminated wastewater and provide a scientific basis for the design, optimization, and scale-up of industrial adsorption systems.