Box-Behnken Response Surface Methodology for Optimization of Process Parameters for Dairy Washed Milk Scum Biodiesel Production

Abstract

ABSTRACTThis study deals with the optimization of process parameters of transesterification of dairy washed milk scum (DWMS) oil to produce biodiesel, using response surface methodology (RSM) and Box-Behnken Design (BBD) along with the application of analysis of variance (ANOVA), to examine the importance of the model parameters at the 95% confidence level. The influence of process parameters such as the molar ratio of methanol to oil, the concentration of KOH, the temperature of the reaction and the reaction time was studied on biodiesel samples. Using a methanol-to-oil molar ratio of 7.5:1, along with a catalyst concentration (KOH) of 1.1 wt. %, an optimum volumetric yield of 92% was obtained at a temperature of 52.5°C over 90 min of reaction time. The quadratic model obtained from results of ANOVA shows that the model was significant and satisfactory. A very small value of p (<0.0001) indicates the strong relationship between biodiesel yield and the model variables. The physicochemical characteristics and gas chromatographic study of the produced DWMS biodiesel proved its suitability as fuel for compression ignition (CI) engines.