Search Results

The aim of this study was to synthesize environmentally adapted Trimethylolpropane (TMP) esters from cottonseed and soybean oils and to examine their quality parameters and tribological properties as potential lubricant basestocks. A two stage production process was followed. At first the above mentioned vegetable oils were transformed to the corresponding methyl esters via methanolysis in the presence of sodium methoxide. The desired TMP esters were finally synthesized by alkaline transesterification of the previously produced methylesters with TMP using sodium methoxide as catalyst. Following the purification phase the physicochemical characteristics of the synthesized TMP esters were examined. The tribological properties were evaluated by employing a Four-Ball apparatus. An additive-free mineral oil base oil was used as a reference lubricating fluid.

The introduction to the European market of higher levels of biodiesel blends focuses the research interest on the compatibility problems of the diesel fuel distribution system. The influence of metals in the oxidation stability and lubricity of two different types of commercially available FAMEs (without antioxidant additive) was investigated. Zinc (Zn), Copper (Cu) and Tin (Sn), were added in the form of solid metals (heterogeneous catalysis in liquid phase oxidation) and examined for their impact on the oxidation stability of biodiesel fuel. Oxidation stability was determined by Rancimat accelerated oxidation method, according to European Standard EN14214. Additionally, in order to examine the effect of the above mentioned metals in the presence of antioxidant additive, BHT was added in both biodiesel samples and oxidation stability determinations were carried out, as well.

The ability of a catalyst to enhance the performance of synthesized biobased lubricant basestock was investigated in this study. Pomace olive oil, cottonseed oil, used frying oil and methyl oleate were utilized as starting materials for the production of the biobased lubricants and a two stages transesterification methodology was followed. Initially the oils were converted to their corresponding fatty acid methyl esters via methanolysis. The resulting methylesters were subsequently transesterified with TMP producing the desired oleochemical ester. These syntheses were carried out in the presence of either sodium methoxide or Ca/TEA alkoxide as catalysts. Following the purification phase, the synthesized esters were evaluated as potential biolubricants regarding their physicochemical properties such as viscosity index, pour point and acid value.