The objective of this study was to test the feasibility of biosurfactant for the removal of oil from used polypropylene nonwoven sorbents and to investigate the effect of basic parameters such as sorbent type, washing time, surfactant dosage and temperature. Biosurfactants are biodegradable and can also enhance the biodegradation of oil by increasing the bioavailability of hydrophobic compounds. Factorial design was employed to examine the oil removal from used sorbents by biosurfactant. The study revealed that pore size, biosurfactant concentration, temperature and washing time exhibit different effects on oil removal for different types of oil. For crude oil and 25% weathered (weight loss from crude oil by evaporation), pore size and washing time are significant factors influencing oil removal from used sorbents. For 50% weathered oil, temperature appears to be most significant factor influencing oil removal. It has been shown that biosurfactant washing has considerable potential for recycling used oil sorbents. Copyright © 2007, Institut français du pétrole.