This study aims determination of transesterification reaction parameters to produce the lowest kinematic viscosity waste cooking oil biodiesel by using sodium hydroxide (NaOH) as catalyst and ethanol (C2H5OH) as alcohol. For this purpose, the individual effects of main reaction parameters such as catalyst concentration (0.50-1.75%), reaction temperature (60-90°C), reaction time (60-150min.) and alcohol/oil molar ratio (6:1-15:1) on the kinematic viscosities of produced biodiesels were investigated, respectively. According to results, reaction parameters giving the lowest kinematic viscosity of 4.387 cSt were determined as 1.25% catalyst concentration, 70°C reaction temperature, 120minutes reaction time and 12:1 alcohol/oil molar ratio

In this paper, energy, exergy and economic evaluation of a single cylinder diesel engine fuelled with diesel fuel and two types of biodiesel-diesel fuel blends (i.e., B10 and B50) were conducted by evaluating experimental data. Experiments were carried out at five different engine speeds and full load conditions. Energy and exergy components of the engine were calculated and compared for each operating conditions and test fuels. Results obtained from biodiesel-diesel fuel blends were found to be better than neat diesel fuel in respect of both energy and exergy analysis. The maximum brake thermal efficiency and exergy efficiency of the test engine were found to be 40.41% and 37.83%, respectively, at 2000 rpm for B10. Also, the minimum exergy destruction occurred at 2000 rpm for all test fuels. However, from the point of specific fuel costs, B10 and B50 gave quite higher economic costs in compared to diesel fuel. Since fuel price per litre of biodiesel is quite higher than diesel fuel, higher biodiesel rates in the blend dominate increase in specific fuel costs even specific fuel consumption decrease.

It is known that blending oxygenated fuels to gasoline can increase knock resistance of the fuel and reduce exhaust emissions. In this experimental research, ethyl acetate as a new and renewable oxygenated fuel which is produced through the reaction of ethanol with acetic acid was added to base gasoline at 5% (E5) and 10% (E10) volume ratios to investigate its effect on engine performance and exhaust emissions. For this, a single-cylinder and four-stroke SI engine was utilized, and engine experiments were carried out under low, medium, high and full load at a constant engine speed of 1500 rpm. The potential for the ethyl acetate as oxygenated fuel was also further investigated by distillation tests. In addition, a fuel cost analysis based on brake specific fuel consumption and fuel price was performed. Results revealed that E5 and E10 displayed superiors in terms of CO and HC emissions to base gasoline. It was determined that oxygen content in ethyl acetate led to decrease in CO and HC emissions by 54.5% and 50.1%, respectively. However, NO_X emissions dramatically increased by 81.1% with fuel blends operation and engine performance parameters such as brake specific fuel consumption (BSFC) and brake thermal efficiency (BTE) deteriorated. Furthermore, the fuel economy analysis showed that 5 vol.% and 10 vol.% ethyl acetate blends with base gasoline presented averagely 38.9% and 84.5% higher fuel cost relative to gasoline.