Modelling the Behaviour of Pollutant Indicators in Activated Carbon Adsorption of Oil and Textile Effluents

Abstract

Simulation studies of adsorption in complex effluents are challenging due to nonlinear interactions between sorbents, adsorbates and carrying flows. This study investigates effluents from oil and textile industries, characterised by their heavy metal content and chemical oxygen demand. It examines the process in a continuous-flow laboratory-scale adsorption system. Results were validated using process modelling based on mass and energy conservation, applied to an industrial adsorber. The model described surface sorption mechanisms on bioactivated carbon at the molecular level and predicted breakthrough curve profiles, integrated with Aspen Plus ® adsorption simulation under industrially relevant conditions. Experimental data and model predictions showed good agreement, with relative deviations ranging from 0.2% to 24.6%. Differences in adsorption capacities between oily and textile effluents highlighted the influence of coexisting constituents. At the same time, the varied behaviour of identical components supported the hypothesis of multifactorial effects in complex mixtures. The optimisation study, using Response Surface Methodology with a Central Composite design, evaluated factors such as bed height, feed rate, and adsorption cycle time, achieving enhanced removal efficiencies of 62% for chemical oxygen demand and 25% for suspended solids.