Chemical and Physical Properties of Biodiesel

Abstract

Although biodiesel is a promising alternative fuels, it still has many challenging issues. One of the problems is its purification process. The traditional wet washing method can increase the production costs so it is important to investigate other reusable and inexpensive purifications methods. In this study, calcium-based desiccants and molecular sieves were investigated as new purification materials. The study showed that the calcium-based desiccants were comparable to wet wash purification for removing volatile byproducts; however, calcium concentration in biodiesel increased dramatically after the treatment. The application of the molecular sieves successfully achieved the reduction of calcium concentration but further experiments will be necessary to determine whether the combination of desiccants can be the replacement for the traditional purification process. In addition, the application of biodiesel is limited due to its poor cold weather properties. In order to improve performance in the cold climate, additives are typically added to biodiesel. The second part of this study focused on the chemical and physical effects on biodiesel using various additives. Results indicated that additives can improve cold weather properties but canola oil, soybean oil, palm oil, and lard based biodiesel with 2 weight-percent of Wintron XC30 and XC40 additives could not achieve the viscosity requirement therefore those additives were not applicable with that concentration. Also, no changes in the chemical structures and freezing point by additives were observed. A faster and novel cloud point analytical methodology using Rayleigh light scattering was developed and applied in this study.