Promotion effect of biosurfactant on heavy-oil biodegradation

ABSTRACT

Biosurfactants have received considerable attention in the field of heavy-oil remediation processes. Heavy oil was used to isolate biosurfactant-producing and oil-degrading bacteria. According to 16S rRNA, the isolated bacteria was identified as Bacillus amyloliquefaciens. The critical micelle concentration (CMC) of the produced biosurfactant was 100 mg/L. Biosurfactant could greatly improve the properties of heavy oil and significantly improve the biodegradation. The viscosity reduction rate was from 24 to 47% over the temperature range of 30–90°C. Biodegradation rates of saturated hydrocarbon (C₁₃–C₃₃) were from 21 to 85%. The biodegradation accelerating rate of biosurfactant for different aromatic hydrocarbon series was 9.89%, 9.60%, 29.71%, 16.75%, and 10.04%. These findings demonstrate that the produced biosurfactant could be useful in environmental remediation processes.

KEYWORDS:

• biodegradation
• bioremediation
• biosurfactant
• heavy oil
• viscosity

Acknowledgments

This work was supported by National Natural Science Foundation of China (Grant NO. 41403067) and Scientific Research Fund of China University of Petroleum, Beijing (KYJJ2012-01-24).