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The purpose of this paper was to analyze palm oil biodiesel production under different conditions and to verify the relationships between production variables in order to optimize biofuel production using response surface methodology (RSM). Biodiesel was produced through transesterification process by methyl route and alkali catalyst (NaOH) 1% (m/m). The analyzed variables were: four molar ratios (3:1, 4:1, 6:1 and 8:1); three temperature reactions (45°, 52° and 60°C); and three time reactions (40, 60 and 80 minutes). For the palm oil biodiesel production, the highest yield was 93%, obtained via a molar rate of 3:1, 52°C and 60 minutes. This result differs from previous studies that found a higher yield with molar ratio increases, implying greater expenses of methanol. Kinetic viscosity and specific mass were also analyzed, and the values are within the Brazilian, American, and European standards. The results showed that the most influent factor in biodiesel production was the molar rate. In relation to the biodiesel characterization, using the RMN H1 technique, it was possible to obtain the transesterification reaction yield of 79.50% for the 3:1 palm oil biodiesel. Through gas chromatography, it can be verified that the predominant fatty acids in the samples were palmitic and oleic acids.

Macbeth model is a multicriteria tool for the multicriteria decision making that has been used in different projects and studies of renewable energies. The purpose of this paper was apply the software Macbeth for the evaluation of canola, corn, palm and soy crops taking in to account technician, environmental and economic criterias and their weights. Canola crop was the best option for the biodiesel production, with a global score of 74 points because of their good score in environmental criterias, wich had a higher weight than the other criterias. Corn crop was the second positioned, presenting good results in all criterias, followed by palm crop. The final one was soy crop with 36,67 points in this analysis.

Diesel cycle engines are widely used in agricultural machinery. Biodiesel offers the possibility of partial or total replacement of mineral diesel, thus reducing the dependence of agriculture on this nonrenewable resource and decreasing pollutant emissions. The objective of this study was to evaluate the emissions of CO, NO x , SO 2 , CO 2 , and O 2 from various biodiesel mixtures (B0 = 0%, B7 = 7%, B10 = 10%, B20 = 20%, B30 = 30% and B100 = 100%) in a single-cylinder tractor engine at 1000, 1600 and 2400 rpm. The exhaust gases were identified using a gas probe meter. Fuels with a higher percentage of biodiesel have the lowest SO 2 emissions, with the B30 mixture releasing 65.78, 52.47 and 32.25 parts per million at 1000, 1600 and 2000 rpm, respectively. Nitrous oxides and carbon dioxide emissions decreases with higher engine rotation speed. Higher percentages of biodiesel result in less polluting fuels.