Cloud point and oxidation stability analysis of turpentine oil and ethanol in b40 biodiesel blend using response surface methodology

Given the availability and the potential of bioresources as blending components of diesel blends, the synergy of turpentine oil and ethanol in the B40 biodiesel blend is presented in this work. Response surface methodology (RSM) was employed to study the influence of both bioresources on the important characteristics of B40 biodiesel blends, i.e., cloud point and oxidation stability. Based on the result, the relationship between turpentine oil and ethanol on cloud point was best expressed with a two-factor interaction (2FI) model. Meanwhile, the quadratic model was more suitable for oxidation stability The most ideal cloud point was found at 10.6 °C in 8% v/v and 0.5% v/v of turpentine oil and ethanol concentration, respectively and the most ideal oxidation induction time was found at 250 minutes in 5% v/v and 0.7% v/v of turpentine oil and ethanol, respectively. It is believed that the rigid structure of turpentine oil is responsible for preventing crystal formation and the ethanol-biodiesel blend attraction also enhances their liquid-phase stability. Furthermore, the oxidation stability of B40 biodiesel blends continues to be maintained at sufficient levels.