Author/Authors :
-، - نويسنده Biotechnology Group, Faculty of New Science and Technology, University of Isfahan, P.O. Box 8174673441, Isfahan, I.R. Iran
and
Chemical Engineering Group, Faculty of Engineering, University of Isfahan, P.O. Box 8174673441, Isfahan, I.R. Iran Salehizadeh, Hossein , -، - نويسنده Chemical Engineering Group, Faculty of Engineering, University of Isfahan, P.O. Box 8174673441, Isfahan, I.R. Iran Mohammadizad, Saleh
Abstract :
A bacterial strain (designated as Alcaligenes sp. MS-103) isolated from oil sample of the Aghajari oilfield in the south of Iran, was able to produce an effective extracellular lipopolysaccharide biosurfactant (1.2±0.05 g/l) on molasses as a sole carbon source. The highest surface tension reduction to level 20 mN/m was achieved by biosurfactant produced by cells grown on molasses under optimum conditions. The optimum values of carbon to nitrogen ratio (C/N), salinity, pH and temperature for biosurfactant production were determined as 60:1, 7.5%, 7.0 and 50°C, respectively. Biosurfactant flooding experiments were carried out on both fractured and unfractured carbonate cores. The highest recovery of residual oil among different experiments was about 10.7% in the unfractured cores. Oil displacement indicates that recovery of crude oil can be increased by 9.2% from fractured core with a permeability of 12 mD. The results showed that the biosurfactant produced by Alcaligenes sp. MS-103 has the potential for industrial applications and may be used in microbial enhanced oil recovery (MEOR).
