Abstract
This study was done to extract hydrocarbon compounds from El-Lajjun oil shale using biosurfactant produced from two strains
Rhodococcus erythropolis and
Rhodococcus ruber. The results have shown that, optimal biosurfactant production was found using naphthalene and diesel as a carbon source for
R. erthropolis and
R. ruber, respectively. Optimum nitrogen concentration was 9
g/l and 7
g/l for
R. erthropolis and
R. ruber, respectively. Optimum K
2HPO
4 to KH
2PO
4 ratio, temperature, pH, and agitation speeds were 2:1, 37
°C, 7 and 200
rpm. Under optimal conditions
R. erthropolis and
R. ruber produced 5.67 and 6.9
g/l biosurfactant, respectively. Maximum recovery of oil achieved with hydrogen peroxide pre-treatment was 25% and 26% at biosurfactant concentration of 8
g/l and 4
g/l for
R. erthropolis and
R. ruber, respectively. The extent desorption of hydrocarbons from the pre-treated oil shale by biosurfactant were inversely related to the concentration of high molecular weight hydrocarbons, asphaltenes compounds. Pre- treatment of oil shale with hydrogen peroxide produced better improvement in aromatic compounds extraction in comparison with improvement which resulted from demineralization of the oil shale.