Asshifa Md Noh Nur, Al-Ashraf Abdullah Amirul, Nasir Mohamad Ibrahim Mohamad, Ramli Mohd Yahya Ahmad
School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia.
J Gen Appl Microbiol. 2012;58(2):153-61. doi: 10.2323/jgam.58.153.
A biosurfactant-producing and hydrocarbon-utilizing bacterium, Pseudomonas aeruginosa USM-AR2, was used to assist conventional distillation. Batch cultivation in a bioreactor gave a biomass of 9.4 g L(-1) and rhamnolipid concentration of 2.4 g L(-1) achieved after 72 h. Biosurfactant activity (rhamnolipid) was detected by the orcinol assay, emulsification index and drop collapse test. Pretreatment of crude oil TK-1 and AG-2 with a culture of P. aeruginosa USM-AR2 that contains rhamnolipid was proven to facilitate the distillation process by reducing the duration without reducing the quality of petroleum distillate. It showed a potential in reducing the duration of the distillation process, with at least 2- to 3-fold decreases in distillation time. This is supported by GC-MS analysis of the distillate where there was no difference between compounds detected in distillate obtained from treated or untreated crude oil. Calorimetric tests showed the calorie value of the distillate remained the same with or without treatment. These two factors confirmed that the quality of the distillate was not compromised and the incubation process by the microbial culture did not over-degrade the oil. The rhamnolipid produced by this culture was the main factor that enhanced the distillation performance, which is related to the emulsification of hydrocarbon chains in the crude oil. This biotreatment may play an important role to improve the existing conventional refinery and distillation process. Reducing the distillation times by pretreating the crude oil with a natural biosynthetic product translates to energy and cost savings in producing petroleum products.
一种产生物表面活性剂且能利用碳氢化合物的细菌——铜绿假单胞菌USM-AR2，被用于辅助传统蒸馏。在生物反应器中进行分批培养，72小时后获得了9.4 g L⁻¹的生物量和2.4 g L⁻¹的鼠李糖脂浓度。通过间苯二酚测定、乳化指数和液滴坍塌试验检测生物表面活性剂活性（鼠李糖脂）。用含有鼠李糖脂的铜绿假单胞菌USM-AR2培养物对原油TK-1和AG-2进行预处理，结果证明通过缩短蒸馏时间而不降低石油馏分质量，促进了蒸馏过程。它显示出缩短蒸馏过程持续时间的潜力，蒸馏时间至少减少了2至3倍。这得到了馏出物气相色谱 - 质谱分析的支持，其中从处理过或未处理过的原油中获得的馏出物中检测到的化合物之间没有差异。量热测试表明，馏出物的热值在处理与否的情况下保持不变。这两个因素证实了馏出物的质量没有受到影响，并且微生物培养的孵育过程没有过度降解原油。这种培养物产生的鼠李糖脂是提高蒸馏性能的主要因素，这与原油中碳氢化合物链的乳化有关。这种生物处理可能在改进现有的传统炼油和蒸馏过程中发挥重要作用。用天然生物合成产物预处理原油以减少蒸馏时间，这意味着在生产石油产品时节省能源和成本。
