Single and multi-component adsorption of toluene, xylene and hexane in disturbed soils

An experimental work was conducted to study the adsorption of petrochemicals hexane, toluene and xylene onto natural sandy soils. Adsorption experiments were performed in complete-mix batch reactors with sandy soils collected from three different locations around Beirut, Lebanon. The results indicated significant difference in potential adsorption of petrochemicals in different soils. The results were discussed and presented in perspective of various physical and chemical attributes of soils and chemicals. Soil properties such as sand equivalency, natural moisture content, particle size distribution and porosity as well as properties of chemicals such as molecular weight, "H/C" atomic ratio and molecular structure appeared to have effect on the adsorption. From the results, an attempt had been made to fit toluene and xylene adsorption data in Langmuir type isotherm model. The isotherm model in its extended form applicable to competitive adsorption was calibrated and subsequently tested for performance reliability. Model adsorption predictability was found to be satisfactory.