用液体石蜡模拟润滑油,采用生物降解试验研究了月桂酸二乙醇酰胺(LDEA)和油酸二乙醇酰胺(ODEA)对液体石蜡生物降解性的影响,采用比浊法测定OD值并结合表面张力变化,分析添加剂促进液体石蜡生物降解机制。结果表明,在液体石蜡中添加LEDA和ODEA培养12 d,生物降解指数从38.78%分别提高到61.67%和65.66%,这是因为烷醇酰胺类物质降低了油-水界面张力,增大了微生物与油的接触面积,同时增加了微生物营养,共同促进液体石蜡生物降解。
Liquid paraffin is used to simulate lubricating oil, impacts of lauric diethanolamide (LDEA) and oleic diethanolamide (ODEA) on degradation of liquid paraffin were tested. The biodegradation mechanism of liquid paraffin promoted by additives were analysed through turbidimetry to measure OD values combined with the variation of surface tension. The results indicate that liquid paraffin medium with LDEA or ODEA after being cultured for 12 days, biodegradation index was raised respectively from 38.78% to 61.67% and to 65.66%. Enhancement of biodegradability of liquid paraffin may be ascribed to reducing the oil-water interfaciai tension, increasing microorganisms and oil contact area, and increasing microbial nutrition provided by alkanolamide surfactants.