Equilibrium adsorption modelling of selected crude oil components following a spill on Niger Delta soil

Abstract

ABSTRACT When crude oil spills on land, it may leach into the soil and reach the groundwater thus posing a threat to drinking water resources. The Niger Delta region provides such an opportunity to study the migration of environmentally important constituents of crude oil in the soil using adsorption models. Soil properties were determined and data obtained from batch equilibrium experiments were applied to nine adsorption isotherms and the characteristic parameters were obtained from the isotherm models. The results show that the clay and organic matter content controlled the rates of infiltration of contaminants into underground water. The correlation values for the isotherms models studied showed that the data from the selected compounds fitted differently to individual isotherms. Adsorption was not monolayer for all adsorbates and the experimental optimum sorption capacity was phenanthrene (100.01 mg g−1), pyridine (33.23 mg g−1), phenol (13.20 mg g−1) and crude oil (10.20 mg g−1). These results indicate that differences in oil residue components and soil property following spillage will determine the type of sorption processes taking place. The model discussed in the study may contribute to the knowledge of the sorption process for technically informed remediation strategy in the Niger Delta region of Nigeria.