Elephant Grass (Pennisetum Purpureum) Mediated Phytoremediation of Crude Oil-Contaminated Soil

Abstract

Phytoremediation is an economic and environmentally friendly method for the remediation of hazardous crude oil contaminated soils. In this study, phytoremediation of crude oil contaminated soils by elephant grass (pennisetum purpureum) was investigated over a 40-day period. Grass clumps were harvested and transplanted into plastic buckets filled with 1kg of soil contaminated with 30 ml and 40 ml of crude oil and an uncontaminated control sample. An additional control sample was contaminated with 30 ml of crude oil with no elephant grass. The samples were analyzed periodically for changes in pH, total hydrocarbon content, total viable bacterial count, and total fungal count. The pH of the soil samples generally ranged from 5.26 to 7.85. After 40 days of treatment, the total hydrocarbon content decreased from 320 mg/kg to 38 mg/kg and from 590 mg/kg to 46 mg/kg in samples contaminated with 30 ml and 40 ml of crude oil respectively. Plant growth was uninhibited in contaminated and control samples as the heights increased by 34.5-42.8 cm. The results of the study further demonstrate the phytoremediation capabilities and tolerance of elephant grass in crude-oil contaminated microcosms.