@Article{, title={Quality Improvement of Spent Lubricating Oil}, author={Huda M. Hassan and Dhia El-Din M. Kassim and Abdul-Hlalim A. K. Mohammed عبد الحليم عبد الكريم}, journal={Iraqi Journal of Chemical and Petroleum Engineering المجلة العراقية للهندسة الكيمياوية وهندسة النفط}, volume={8}, number={3}, pages={31-35}, year={2007}, abstract={The acidity of spent lubricant was treated using sodium hydroxide solution. The effect of three variables on the treatment have been studied. These are mixing time ranging from 5-35 minutes, NaOH to lubricant weight ratio ranging from 0.25-1.25 and weight percentage of NaoH ranging from 2.6%.The experimental design of Box-Wilson method is adopted to find a useful relationship between the three controllable variables and the lowering in the acidity of the spent lubricant. Then the effective variables and interactions are identified using the statistical analysis(F-test) of three variable fractional design. The mathematical model is well represented by a second order polynomial.By the analisys of the experimental results, the best treatment conditions which achieved an acceptable acidity of the spent lubricant are 20 minutes mixing time, I weight ratio of NaOH to spent lubricant and 4.5 weight percentage of NaOH. At these condition the acidity of the lubricant decreases from 0.62 to 0.0602mg KOH/g oil.

} }