(211c) Optimization of Biodemulsifier Production Condition in Order to Crude Oil Demulsification

Paenibacillus alvei ARN63 as a biodemulsifier-producing bacterium has represented incredible demulsifying ability. The produced lipopeptide biodemulsifier 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 cell growth were determined via measurement of surface tension and optical density (OD600nm), respectively. Subsequently, to investigate its demulsification performance, the bottle test was carried out. Normal paraffin compounds such as C₁₀H₂₂ and C₁₂H₂₆and motor oil favored the synthesis of this biodemulsifier. The best results were obtained employing motor oil as carbon source with a concentration of 50 ml/l. The biosurfactant (biodemulsifier) production was probably growth associated as resulted from the biosurfactant production and growth kinetics. The surface tension was reduced (from 58 mN/m) to 24.7 mN/m in 72 h, and demulsification ratio reached to approximately 73%. Under optimal conditions, the biodemulsifier yield approached 2.1 g/l.