Evaluation of the ex-situ bioremediation of the petroleum hydrocarbons contaminated soil

This study aimed to effectively decontaminate fuel oil-contaminated soil using ex-situ bioremediation. Soil samples (contaminated with waste oils) from Serbia were treated. The results showed several significant changes after bioremediation. The pH levels became slightly more alkaline (7.0-7.5). Reduction in organic substance (34%) and carbonate (36%) were observed, respectively. The concentration of n-hexane extractable substances and total petroleum hydrocarbons decreased by around 90%, including a significant reduction in hydrocarbons containing 17 C and 18 C atoms. Total carbon, organic carbon, and total hydrogen content also decreased notably. The presence of a high number of microorganisms indicated active aerobic and anaerobic processes in the soil. Overall, the results confirmed a high degree of feasibility of the applied conditions for bioremediation of soil contaminated with waste oils.