a Jahanmiri - School of Chemical and Petroleum Engineering, Department of Chemical Engineering, Shiraz
Shahab Amirabadi
Babak Rafie nia
M.R Rahimpour

Paenibacillus alvei ARN63 as a biodemulsifier-producing bacterium has represented incredible demulsifying ability. The produced lipopeptidebiodemulsifier can be used in crude oil industry as an environmentally friendly(green) substance, containing no toxic component. Due to increase production of biodemulsifier, as a type of biosurfactant, the culture conditions for the strain were optimized. For this goal, the effect of different carbon sources and C/N ratios(carbon concentration) were examined in detail at constant temperature, pH, shaking speed (rpm) and nitrogen source. Biodemulsifier synthesis and cellgrowth were determined via measurement of surface tension and optical density (OD600), respectively. Subsequently, to investigate its demulsificationperformance, the bottle test was carried out. Normal paraffin compounds such as C7H16 and C10H22 and C12H26 favored the synthesis of this biodemulsifier. Thebest results were obtained employing C7H16 as carbon source with C/N ratio of 63.13. The surface tension was reduced (from 62.5 mN/m) to 32.3 mN/m in 72 h, and demulsification ratio reached to approximately 65%.

Biodemulsifier, biosurfactant, carbon source, normal paraffins, surface tension, crude oil emulsion