ABSTRACT The depletion of fossil fuels is eminent over time due to its non-renewable nature. The use of biodiesel is a viable option to stop its decline since it is obtained from biomass. Due to the importance of the percentage of biodiesel that can be added without affecting the operation of the MWM International model 6.10T engine coupled to a Worthington vertical deep well pump. This research was developed in the Department of Engineering and Environment, of the Institute of Animal Science. The pumping system used in the water supply for the institute and the community was evaluated. Biodiesel-diesel blends (B-0, B-5, B-10, B-15, B-20, B-25 and B-30) were handled with three rotation frequencies (1350, 1550, 1750 min-1). The hourly consumption (Gh) did not show statistically significant differences in the rotation frequencies 1350 and 1550 min-1, only at 1750 min-1 the highest consumption is obtained when using 30% biodiesel. The specific fuel consumption (ge) at 1750 min-1 showed statistically significant differences only in B-30 and at 1350 min-1 the highest consumption was observed in B-5 and B-30. When the engine is running for 1000 hours of work, the B-20 and B-25 blends obtain the most economically efficient values, with 9 780 and 9 070 pesos, respectively. By studying all the blends analyzed, it can be stated that B-20 and B-25 are the most recommended to use.

RESUMEN El agotamiento de los combustibles fósiles es eminente en el transcurso del tiempo por su carácter no renovable. El uso de biodiesel es una opción viable para frenar su disminución ya que su obtención proviene de la biomasa. Por la importancia que reviste el tema, se requiere determinar el porcentaje de biodiesel que se puede añadir sin afectar el funcionamiento del motor MWM Internacional modelo 6.10T acoplado a una bomba vertical de pozo profundo marca Worthington. La presente investigación se desarrolló en el departamento de Ingeniería y Medio Ambiente, del Instituto de Ciencia Animal. Se evaluó el sistema de bombeo que se usa en el abastecimiento del agua para el instituto y la comunidad. Se manejaron mezclas diésel-biodiesel (B-0, B-5, B-10, B-15, B-20, B-25 y B-30) con tres frecuencias de rotación (1350, 1550, 1750). El consumo horario (Gh) no evidenció diferencias estadísticamente significativas en las frecuencias de rotación 1350 y 1550 min-1, solo en 1750 min-1 se obtiene el consumo más elevado al utilizar el 30% de biodiesel. El consumo específico de combustible (ge) a 1750 min-1 demostró diferencias estadísticamente significativas solo en B-30 y en 1350 min-1 el mayor consumo se observó en B-5 y B-30. Al estar el motor en funcionamiento durante 1 000 h de trabajo, las mezclas B-20 y B-25 obtienen los mejores valores con respecto a la eficiencia económica, con 9 780 y 9 070 peso, respectivamente. Al estudiar todas las mezclas analizadas se puede afirmar que B-20 y B-25 son las más recomendables para utilizar.

Natural additives with antioxidant properties can be used as biodegradable and sustainable alternatives to synthetic products, because they can inhibit the biodiesel oxidation reaction, increasing oxidative stability and extending its storage period. This research evaluated the efficiency of jabuticaba peels, gabiroba leaves, and hibiscus flowers in ethanolic extracts, analyzing through the simplex-centroid design, the induction periods (IP) and rate constants (k) of the biodiesel oxidation reaction at 110 °C. Antioxidant activity was observed in all extracts, either decreasing k or increasing the IP. The mathematical models obtained showed coefficients of determination greater than 0.9400, a non-significant lack of fit at the 5% level, and low dispersion between predicted and experimental data, indicating that the 1st order reaction fit was appropriate and can be used for predictive purposes. In this work, the optimization was performed with maximization of IP and minimization of k showing that the mixture containing 25% of jabuticaba peels extract and 75% of gabiroba leaves extract was the most suitable, because proportionally increased the IP and decreased k of the biodiesel oxidation reaction. It is possible to suggest the use of jabuticaba peels extract or gabiroba leaves extract as well as various combinations between them as antioxidant additives.

Abstract The total cost of processes that use lipases can be reduced by using the mycelium or not purified crude extract with lipolytic activity. These catalysts can be used without complex purification and can show desirable properties to emerging applications like hydrolysis and biotransformation of vegetable oils. To explore the potential of multiple forms of lipases (produced by the same filamentous fungus species), this work investigated intracellular and extracellular lipases produced by Trichoderma koningii (intracellular lipases were never studied), Penicillium spp. F02 (isolated from industrial grease trap) and Aspergillus niger. For this, batch fermentations were conducted for 96h using olive oil as a carbon source. The submerged culture was interrupted with vacuum filtration to isolate the mycelium and crude extract. The lipolytic activities were determined by the hydrolysis method of olive oil. The best results were obtained for intracellular activity with T. koningii (81.5 U/g of dry biomass) and for extracellular activity with A. niger (10.6 U/mL of crude extract). Both were attained in 96h of fermentation. T. koningii showed an accumulation of intracellular lipases and a depreciated extracellular activity in the initial 24 hours, which can be reasonable indications that there is strong retention of lipases in the mycelium. Statistical analysis within the range of 37°C to 44°C associated with pH from 7.8 to 8.0 favored the activity of lipases from T. koningii. All these findings are promising for future studies in the enzymatic synthesis of biodiesel with lipases (intracellular and extracellular) from T. koningii.

Resumen La demanda de diésel en vehículos pesados se incrementa cada año en el mundo. El posible uso de combustibles alternativos como el biodiésel tiene algunas desventajas como el menor valor calorífico y su mayor viscosidad, por esta razón se requiere mejorar sus propiedades, optimizando el comportamiento de la combustión en el motor y en la reducción de las emisiones. El objetivo del trabajo de investigación es explorar las diferentes mezclas que puedan ayudar a mejorar el uso del biodiésel a través de las estrategias y avances que se han generado con el propósito de beneficiar el desempeño del motor diésel. Entre las distintas estrategias de mejoramiento del biodiésel están las mezclas de distintos bioaceites (aceites vegetales, de pirólisis y usado de cocina), mezclas del biodiésel con alcohol, con hidrógeno, el biodiésel como combustible piloto, las emulsiones del biodiésel con agua y la aplicación del biodiésel con antioxidantes, nanotubos y nanopartículas. Se concluye que para poder usar actualmente el biodiésel se lo haría con la combustión dual, en donde este representaría el combustible piloto (10 % o 20 % del combustible total del motor). Con esta estrategia se puede impulsar a otros combustibles (líquidos y gaseosos) en la combustión dual, para que con el paso del tiempo se encuentre la mezcla óptima que sea la mejor opción para el motor diésel.

Abstract The demand for diesel in heavy vehicles is increasing every year in the world, the possible use of alternative fuels such as biodiesel has some disadvantages such as the lower calorific value and its greater viscosity, for this reason biodiesel needs to improve its properties, optimising combustion behavior in the engine and helping to reduce emissions. The objective of the research work is to explore the different mixtures that can help improve the use of biodiesel through the strategies and advances that have been generated with the purpose of benefiting the performance of the diesel engine. Different biodiesel improvement strategies include blends of different biooils (vegetable oils, pyrolysis oils and used cooking oil), blends of biodiesel with alcohol, biodiesel as pilot fuel, biodiesel emulsions with water, biodiesel blends with hydrogen and the application of biodiesel with antioxidants, nanotubes and nanoparticles. It is concluded that to be able to use biodiesel currently is applying dual combustion, where biodiesel would represent as pilot fuel (10% or 20% of total engine fuel), with this strategy can be propelled to other fuels (liquid and gaseous) in dual combustion, so that over time the optimal blend of biodiesel is found and is the best choice for the diesel engine.

This paper evaluates the different socioeconomic impacts of the biodiesel sector on family farming and other sectors of the economy of the states of Rio Grande do Sul and Mato Grosso, which are the largest biodiesel producers in Brazil and have structural and regional differences. The Input-Output Theory was the methodology used to measure the direct and indirect effects on the jobs generated and on the Gross Domestic Product (GDP). The research shows that the production of biodiesel via family farming in Rio Grande do Sul is 66 times that of Mato Grosso, generating approximately 19,000 jobs, which is explained by the greater development of the agricultural sector in Rio Grande do Sul. Compared to fossil diesel, one million barrels of oil equivalent of family biodiesel in Rio Grande do Sul generates 7,700 jobs, while the fossil route generates 1,600 jobs.

Este trabalho tem o objetivo de avaliar os diferentes impactos socioeconômicos do setor do biodiesel na agricultura familiar e demais setores da economia dos estados do Rio Grande do Sul e do Mato Grosso, que são os maiores produtores de biodiesel no Brasil e possuem diferenças estruturais e regionais. Utilizou-se como base metodológica a Teoria de Insumo-Produto para mensurar os efeitos diretos e indiretos nas ocupações geradas e no Produto Interno Bruto (PIB). Os resultados indicam que a produção de biodiesel via agricultura familiar no Rio Grande do Sul é 66 vezes àquela no Mato Grosso, gerando aproximadamente 19 mil ocupações, que é explicado pelo maior desenvolvimento do setor agrícola gaúcho. Na comparação com o diesel fóssil, um milhão de barris equivalentes de petróleo (bep) de biodiesel familiar no Rio Grande do Sul gera 7,7 mil ocupações, enquanto na rota fóssil gera 1,6 mil ocupações.

Abstract Heterogeneous catalysts, especially those produced with functionalized clays, can be used for methyl transesterification at moderate temperatures. The use of bentonite clay functionalized by potassium compounds (KF, KOH, K2CO3, KCl and K2SO4) in the methyl transesterification of cottonseed oil is the object of the present study. The catalysts were produced by contacting aqueous solutions with the clay and subsequent drying. The catalysts were characterized by Hammett indicators to determine alkalinity. The methyl transesterification reactions were made in a flask with stirring and reflux at 70°C for 2 h. The performance evaluation of the reaction was carried out using regression between the absorption band area and the concentration of a biodiesel-oil mixture by infrared spectroscopy. The catalytic activity is directly associated with the alkaline character of the catalysts. The catalysts produced with KCl and K2SO4 did not show conversion in the methyl transesterification reaction, while the catalysts produced with KF, KOH and K2CO3 showed a conversion greater than 90%.

Resumen Jatropha curcas pertenece a la familia Euphorbiaceae, originaria de México y Centro América, actualmente crece en regiones tropicales y subtropicales del mundo. Es una planta multipropósito, cuyo interés en los últimos años está relacionado a su potencial como materia prima para producción de biodiesel. El objetivo de esta investigación fue evaluar las características morfológicas y productivas de accesiones de Jatropha curcas L., no tóxicas, recolectadas en distintas regiones de Veracruz y que fueron propagadas por semilla en la región centro del estado en el año 2019. El material vegetal consistió en 23 accesiones con cinco repeticiones, plantas que tenían tres años. Las variables registradas fueron: altura de planta, diámetro de tallo, ramas (primarias, secundarias, terciarias), longitud y ancho de hoja, brotes florales, número de racimos y frutos; longitud, ancho, color y número de semillas por fruto, en semillas se registró el peso, longitud, ancho, espesor y peso total de semillas por planta. El análisis de varianza detectó diferencias significativas (p≤ 0.05) entre accesiones para la mayoría de las variables. El análisis de componentes principales, los primeros dos explicaron 57.66% y 60.80% de la variación. En accesiones propagados por semilla las variables sobresalientes fueron: brotes florales, racimos, frutos y producción de semilla (accesiones I-34, I-32 e I-47). Estas accesiones tienen el mayor potencial y vigor para ser incluidos en un programa de mejoramiento genético. Se concluye que existe una amplia variación morfológica en las accesiones estudiados.

Abstract Jatropha curcas belongs to the family Euphorbiaceae, native to Mexico and Central America, currently grows in tropical and subtropical regions of the world. It is a multipurpose plant, whose interest in recent years is related to its potential as a raw material for biodiesel production. The objective of this research was to evaluate the morphological and productive characteristics of accessions of non-toxic Jatropha curcas L., collected in different regions of Veracruz and that were propagated by seed in the central region of the state in 2019. The plant material consisted of 23 accessions with five repetitions, plants that were three years old. The variables recorded were: plant height, stem diameter, branches (primary, secondary, tertiary), leaf length and width, flower buds, number of clusters and fruits; length, width, color and number of seeds per fruit, in seeds the weight, length, width, thickness and total weight of seeds per plant were recorded. The analysis of variance detected significant differences (p≤ 0.05) between accessions for most variables. The principal component analysis, the first two explained 57.66% and 60.80% of the variation. In seed-propagated accessions, the outstanding variables were: flower buds, clusters, fruits and seed production (accessions I-34, I-32 and I-47). These accessions have the greatest potential and vigor to be included in a genetic improvement program. It is concluded that there is a wide morphological variation in the accessions studied.

Resumen En este artículo se hace una revisión sobre la producción de biocombustibles desde el punto de vista de la catálisis. Se describen los tipos de biocombustibles existentes y se analiza la necesidad de utilizarlos. Para los cuatro biocombustibles más importantes: bioetanol, biodiésel, diésel verde y biocrudo se describe la forma de producción y el tipo de catalizador que se utiliza en su producción.

Abstract This article reviews production of biofuels from the point of view of catalysis. It describes existing types of biofuels and analyses the need for them. For the four major biofuels: bioethanol, biodiesel, green diesel and bio-oil, the form of production and type of catalyst used in their production are described.

The objective of the present work was to apply self-organizing feature maps (SOFM) and multilayer perceptron (MLP) to evaluate the protective capacity of tert-butylhydroquinone (TBHQ), butylhydroxyanisole (BHA), and butylhydroxytoluene (BHT) antioxidants against the biodiesel oxidation reaction. For this, the antioxidant concentration and the biodiesel compliance parameters were used as continuous input variables and the type of antioxidant as a categorical. The SOFM proved to be an adequate tool for the classification of biodiesel samples containing antioxidants. The performance of the 5 most active networks of the model ranged from 89 to 99% for training, testing, and validation with an error below 1.42 × 10-4. Statistical tests applied to validate the model showed no significant difference between predicted and experimental values. The global sensitivity analysis showed that the relative protection factor (RPF) contributed with 34.89%, the antioxidant with 31.49%, the induction period with 10.69%, the water content with 6.00%, and the others all together with 16.93% in the construction of the regression models by MLP.

A new approach involving square wave anodic stripping voltammetry was developed to simultaneously determine cadmium and lead and, in the same cell, sequentially copper, in biodiesel after extraction induced by microemulsion breaking. The composition of the water-in-oil microemulsion involved 10.50 mL biodiesel, 4.20 mL n-propanol and 0.30 mL of the 6.0 mol L 1 HNO3 solution. The extraction was carried out by adding 1.10 mL ultrapure water resulting in two well separated phases: an upper organic phase, and a lower aqueous phase containing the analytes. The apparatus comprised a portable potentiostat and a cell with an in situ plated mercury film glassy carbon electrode as working electrode. The limits of detection for Cd, Pb and Cu were 0.33, 0.48 and 0.66 µg L 1, respectively. The accuracy of the method was evaluated by recovery assays of spiked samples and by analyzing a standard reference material.

The approach proposed here is focused on the separation of light fractions (corresponding to fatty acids with molecular chains between 8 to 14 carbons) from the fatty acid methyl esters (FAMES) of the biodiesel obtained by the reaction of transesterification of triacylglycerols in the kernel gueiroba oil (Syagrus oleracea) with methanol. The whole biodiesel was fractionated through atmospheric distillation in a single glass column with thermal insulation. Such a separation produced 59.79% in volume of light biodiesel (LB), which was mixed with the standard mineral Jet-A1 kerosene (cf. ASTM, corresponding to the QAV-1, cf. the Brazilian standard of the ANP) for aviation, in the volumetric ratios LB:Jet-A1 2:98; 5:95; 10:90 and 20:80. The values of density, water content, distillation analysis, flash point, calorific value and freezing point were carefully checked for their compliance with the official recommendations for jet fuel. It was found that the mixtures richest in the Jet-A1 mineral kerosene, that is, those containing no more than 5% LB by volume, well meet the recommended standards and are technologically viable to replace pure Jet-A1 kerosene for the propulsion of turbine aircraft.

RESUMO Os motores ciclo diesel são amplamente empregados para a execução das mais diversas atividades agrícolas. Recentemente, com o incremento da utilização do biodiesel em mistura ao diesel de petróleo e o início da vigência da regulamentação de emissões de poluentes em máquinas agrícolas e rodoviárias, ocorreu uma crescente migração do sistema mecânico de injeção para o sistema de injeção eletrônica de combustível. Neste experimento, o objetivo principal foi verificar o comportamento de um motor diesel, gerenciado eletronicamente, com variação controlada dos parâmetros, momento de injeção e volume injetado, do sistema de alimentação de combustível. Foi utilizado um trator agrícola com motor de quatro cilindros, sobrealimentado e com injeção eletrônica de combustível common rail. Foram realizados ensaios com diesel B10 e misturas de 20 e 30% de biodiesel, todos com 10 ppm de enxofre, e realizada a reprogramação eletrônica do sistema de injeção. Os ensaios foram realizados em regime de carga plena do motor de 1.300 a 2.000 rpm. Foram avaliados o torque, a potência e o consumo de combustível. O avanço do ponto de injeção aumentou a potência e diminuiu o consumo específico de combustível em todos os combustíveis. A maior quantidade de combustível injetado proporcionou ganho de potência médio de até 14,96% e de torque médio de 15,50%.

ABSTRACT Diesel cycle engines are widely used in a wide range of agricultural activities. Recently, with the increasing use of biodiesel mixed with petroleum diesel and the introduction of pollutant emission regulations for agricultural and road machinery, there has been a growing migration from mechanical to electronic fuel injection systems. In this experiment, the primary aim was to verify the behavior of a diesel engine, electronically managed, with controlled variation of the fuel feeding system parameters (injection time and volume injected). A four-cylinder agricultural tractor with a turbocharged engine and a common rail electronic fuel injection system was used. Tests with diesel B10 and blends of 20 and 30% biodiesel were carried out, all with 10 ppm of sulfur and the injection system electronically reprogrammed. The tests were performed under full engine load from 1,300 to 2,000 rpm. The torque, power and fuel consumption were evaluated. Advancing the injection point increased the power and decreased the specific fuel consumption for all fuels. The greater amount of injected fuel provided average power gain of up to 14.96% and average torque gain of 15.50%.

Abstract CuCrO2 was synthesized by solution combustion synthesis (SCS) and applied as a heterogeneous catalyst to produce soybean biodiesel. The combustion reaction was carried out using urea as a fuel, and copper (II) and chromium (III) nitrates as precursors. After the powders’ obtention, these were calcined and functionalized in an acidic medium. The powders were characterized by thermogravimetry (TG), X-ray diffraction (XRD), scanning electron microscopy (SEM), and infrared spectroscopy (IR) techniques. The TG curve revealed that the formation of the CuCrO2 in the combustion reaction remained stable up to 1000 °C. The XRD results confirmed the formation of the CuCrO2 compound. The SEM images showed that the crystallinity of the samples increased after the calcination process. The IR spectra showed the presence of delafossite characteristic bands. After the transesterification reaction, biodiesel was obtained with a yield of around 80%. Thus, catalysts based on delafossite synthesized through the combustion method and functionalized showed to be promising for the transesterification reaction of vegetable oils.

Catalyst performance is a relevant factor in biodiesel production because it can affect the efficiency of the process. This work provides a study of the performance of heterogeneous catalysts for biodiesel production derived from thermal-treated hydrocalumite-type compounds. This work aimed to synthesize and characterize hydrocalumite-type compounds intercalated with chloride and nitrate, evaluate the effect of thermal treatments at different temperatures (500, 600, and 750 °C) on these materials, and assess the performance of these materials as catalysts in the transesterification reactions using soybean oil and methanol. The materials were characterized by X-ray diffraction (XRD), vibrational spectroscopy (Fourier transform infrared with attenuated total reflectance (FTIR-ATR)), thermogravimetric analysis coupled to mass spectrometry (TGA DSC-MS), specific surface area, and X-ray photoelectron spectroscopy (XPS). The results of the transesterification reactions showed that the thermal-treated materials from the hydrocalumite intercalated with chloride presented high catalytic activity, among them, the thermal-treated material at 750 °C presented the highest conversion to methyl esters.

The objective of this study was to evaluate the effect of replacing grain sorghum (GS) with palm kernel cake (PKC) on the performance, carcass traits and meat quality of feedlot steers fed high-grain diets. Forty male ¹/4 Holstein * ¹/4 Nellore steers with an initial weight of 331.1 ± 36.2 kg, at 24 ± 2 months of age, were housed in group stalls (10 cattle/stall) where they received diets containing 0, 80, 160, or 240 g/kg PKC on a dietary dry matter basis. After 126 days, the animals were slaughtered and their carcass and meat evaluated. The replacement of GS with PKC did not influence empty body weight, carcass weight, carcass length, or carcass yield. However, the thickness of subcutaneous fat in the carcass decreased with the replacement of GS with PKC. The meat pH increased linearly, whereas there were no changes in cooking loss, shear force, lightness (L*), and fat or cholesterol contents in the meat of the steers. Partial replacement (41,57%) of GS with PKC is recommended, with an inclusion of up to 240 g/kg PKC in high-grain diets for steers.