以柴油培養之Rhodococcus erythropolis NTU-1結塊處理水包油(O/W)型乳化液

Abstract

NTU-1是從石油汙泥中分離並透過16S rDNA序列鑑定確立其所屬菌屬為Rhodococcus erythropolis。經由培養、烘乾後，可得到NTU-1結塊之粉末，此粉末具有很好的破乳化能力。 本研究比較以柴油培養的NTU-1粉末及以正十六烷培養的NTU-1粉末之破乳化效率。經實驗結果發現，以柴油培養的NTU-1粉末具有生產成本較低、使用量較少以及破乳化能力較佳之優勢。若以柴油培養的NTU-1粉末進行破乳化測試，其最適添加量與Tween-80體積存在著三分之二次方的關係。於O/W/T比例為4/1/0.01，在480分鐘時油相回收百分比可達95%。此外，當乳化液的油/水比(O/W)較大時或連續相黏度較低時，可提升油相回收百分比。細胞表面疏水性是影響破乳化重要的因素。實驗結果顯示，微生物細胞疏水性與油相回收百分比呈現正相關。 綜括上述，以烘乾後的NTU-1粉末處理水包油(O/W)型乳化液具有相當的潛力以及發展性。

NTU-1, a highly efficient demulsifying strain, was isolated from petroleum contaminated soil and identified as Rhodococcus erythropolis by 16S rDNA gene analysis. NTU-1 powder with high demulsifying performance could be obtained by heat-drying after collecting bioflocculi in medium. This study first evaluated the demulsifying performance of NTU-1 cultured by diesel and n-hexadecane, and found that NTU-1 powder by diesel is a better choice for its lower cost and better performance. At an optimal quantity of dried NTU-1 powder for de-emulsification that was proportional to the volume of Tween-80 to the 2/3 power, a recovery of 95 % oil was achieved in 480 min. This was made possible when the oil/water/Tween80 volume ratio was set at 4/1/0.01. The higher O/W ratio and the lower viscosity both contributed to such a high oil recovery rate. The positive correlation between CSH (MATH) and oil recovery ratio also implies that the diesel grown NTU-1 culture may provide a commercial scale-up method to break oil -in-water emulsion directly at the primary oil recovery site.