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To produce biodiesel, one of the most important factors is the quality of the oil used in the production. However, other factors such as price and availability should also be taken into consideration. Chicken wastes oil shows a very promising option for this sector, since it comes from a waste. The aim of the present study was a methodology for extraction and characterization of chicken wastes oil for production of biodiesel by ethylic transesterification, besides presenting the characterization and optimization of the process variables of the production of biodiesel, the applying of RSM involving CCD. The investigation was performed following evaluation of the characterization parameters for the oil: viscosity, density, acidity index, moisture of the sample, refractive index, and saponification index. For biodiesel, viscosity, density, acidity index and ester content were evaluated. An optimum point was reached for the production of chicken biodiesel where the concentration of the catalyst is 2.1% by mass, the oil/ethanol ratio is 1:5.5 and the reaction temperature of 30 °C; at that point, a 95% conversion was achieved. At the optimum point obtained from the statistical technique for a p-value of 0.05 the results found for the physical-chemical characterization of biodiesel are found in the ANP standards. [ABSTRACT FROM AUTHOR]

Waste glycerol from biodiesel production is a valuable raw material that has been used to produce valuable microbial metabolites. In this work, the possibility of microbial utilization of waste glycerol obtained as a by-product in biodiesel production from sunflower and rapeseed oil by the lactic acid bacterium Enterococcus faecalis MK3-10A on a laboratory level was studied. For comparison, pure glycerol and glucose were used as carbon sources. The kinetics of the microbial biomass growth, the carbon source utilization, and the lactic acid production were monitored. The bacterium E. faecalis MK3-10A better grew in the media with glucose or pure glycerol as a carbon source, but the lactic acid production rate was the highest (14.6 mg/(ml/day)) in the medium with waste glycerol from the sunflower oil-based biodiesel production. Therefore, this waste glycerol might be a promising carbon source for lactic acidbacteria cultivation and lactic acid production. [ABSTRACT FROM AUTHOR]

Glycerol is the main byproduct of industrial biodiesel plants, and new technological routes using it as feedstock have been studied, due to the increase in world biofuel production. One of the possible applications is in the production of acrylic acid, a product with several industrial applications. This study analyzed a new process of converting crude glycerol, through purification for the removal of impurities, followed by oxidative dehydration reaction in a single step and purification until glacial acrylic acid specification standards are met. It was attested that the process is economically viable, with a payback period of 5 years for an NPV/Investment greater or equal to 2 and an IRR greater or equal to 10% per annum, or 4 years in case tax incentives offered for the development of green technologies. [ABSTRACT FROM AUTHOR]

The biodiesel inclusion in the Brazilian energy matrix still faces challenges due to the lack of diversity of raw material and the high costs associated with the stages of production, purification and phase separation of the biofuel. In this work, the potential of Catolé (Syagrus cearensis) was evaluated as an alternative source for biodiesel production, through methyl transesterification by alkaline catalysis. Given the absence of reported data on this oilseed, the aim of the present paper is to characterize the oil and biodiesel in terms of density, kinematic viscosity, and acid value. A liquid-liquid equilibrium (LLE) study of Catolé biodiesel-methanol-glycerin systems at 298.15, 308.15 and 323.15 K at atmospheric pressure was also carried out. Results showed that Catolé seed oil is a viable alternative for biodiesel production, with parameters found in accordance with the quality standards and an ester yield of 97.1%. Ternary diagrams showed that the solubility of the components lowers at low temperatures. Tie-lines evidenced higher affinity of methanol with the glycerin-rich phase. Distribution and selectivity coefficients were determined and the Othmer-Tobias and Hand correlations were applied to verify the quality of the experimental data. The determination indices (>0.97) proved the thermodynamic consistency of the data. [ABSTRACT FROM AUTHOR]

Alkaline transesterification of vegetable oils or animal fats (apolar substances) with a short-chain alcohol (polar substance) is the best-known chemical route for biodiesel production. However, because they are substances of different polarities, there is a need to promote contact between the phases. Biodiesel was produced from soybean oil, methanol, potassium hydroxide, and surfactants DBB 7104 and DBB 7107. In this paper we verify whether it is better to use surfactant DBB 7104 or DBB 7107, and if there is an optimum experimental condition for the surfactant. The yield in biodiesel was verified for different production conditions on a bench scale. From a fractional experimental plan (26-2), with a variation of temperature, time, methanol-to-oil mole ratio, weight of surfactant, type of surfactant and weight of catalyst, it was possible to perform a multivariate analysis of the process. The most influential variables in the response were the temperature and the weight of the catalyst. Surfactant DBB 7107 was considered better than the surfactant DBB 7104. The optimal conditions were 0.7% w/w of the surfactant DBB 7107, 1 g of KOH, 30 min, methanol to oil mole ratio of 6:1 and temperature equal to 33.5 °C. [ABSTRACT FROM AUTHOR]

A lot of recent research has focused on the study of biocatalysts and nanocatalysts to improve biodiesel production. However, knowledge of the thermodynamic properties of the reaction components is necessary. In this work, the enthalpy of formation and Gibbs free energy of formation for methyl to pentyl esters were calculated using the Gaussian quantum chemistry software (model B3LYP/6-31G(d, p)) and the group contribution method of Constantinou and Gani (MCG). The values obtained by both methodologies present certain differences in relation to the values in the literature. Thus, three correction parameters, which were based on the number of atoms of 26 different molecules, were estimated by minimizing the error function and later used to extrapolate the results to larger molecules of interest. After the use of the correction parameters, the mean deviation between the experimental and calculated values by Gaussian was 0.723% for enthalpy and 1.087% for Gibbs, whereas for MCG, it was 1.324 and 2.540%, respectively. As the methodology proved to be efficient, the thermodynamic properties of the formation of 23 esters that compose the biodiesel were estimated. These properties are of great importance, mainly for the calculation of chemical equilibrium and reaction data in the development of new catalysts. [ABSTRACT FROM AUTHOR]

The manganese carbonate catalyst, prepared by precipitation method, was used in transesterification of soybean oil under subcritical condition of methanol. Catalyst samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). The triacylglycerol (TAG) conversion and fatty acid methyl esters (FAME) yield were determined using high performance liquid chromatography (HPLC). The transesterification was realized for 1 h using various working conditions: 0-3 wt.% of catalyst (based on the mass of oil), the mole ratio of methanol to oil from 13:1 to 27:1 and temperature ranging from 393 to 473 K. A maximum TAG conversion of 98.1% could be obtained at the optimal reaction conditions: 2 wt.% of catalyst, methanol/oil mole ratio of 21:1, for 1 h in a batch reactor at 453 K. Kinetic analysis showed that the model based on mass transfer and chemical reaction at the catalyst surface confirmed the experimental data. Using that kinetic expression, the effect of continuous transesterification was proposed and verified by a 360-h long realized experiment in a laboratory packed-bed reactor (PBR). Slow deactivation of the catalyst was caused by leaching of Mn in both biodiesel and glycerol phases and by blocking the active sites of the catalyst with organic compounds. [ABSTRACT FROM AUTHOR]

The ethanolysis of sunflower oil catalyzed by calcium oxide was studied in a wide range of reaction conditions: temperature 65-75 °C, ethanol-to-oil mole ratio 6:1-18:1 and catalyst loading 10-20% in order to determine the reaction kinetics. The proposed kinetic model of sunflower oil ethanolysis included the changing and first-order reaction mechanism with respect to triacylglycerols and fatty acid ethyl esters. The kinetic parameters were determined and correlated with the process variables. The Arrhenius equation could be applied to the reaction rate constant with the activation energy of 94.0 kJ/mol. The proposed kinetic model showed a good agreement with the experimental data with a mean relative percentage deviation of ±13% (based on 256 data points). [ABSTRACT FROM AUTHOR]

Vegetable oils are mainly esters of fatty acids and glycerol, which can be converted to fatty acid methyl esters (FAME), also known as biodiesel, by the transesterification reaction with methanol. In order to attain environmental benignity, much attention has been focused in the last decades on utilizing heterogeneous catalysts for biodiesel production instead the homogenously catalyzed transesterification of vegetable oil. The pure CaO or CaO mixed with some other metal oxide due to its low solubility in methanol, FAME and glycerol, low cost and availability, is one of the most promising among the proposed heterogeneous catalysts. Solid catalysts containing CaO usually fulfill a number of important requirements, such as high activity at mild temperature, marginal leaching of Ca cations, long life activity, reusability in transesterification of vegetable oil and easy recovery from the final products of trancesterification (FAME and glycerol). This review is focused on the recent application of pure CaO or CaO in complex catalyst structure and their use as heterogeneous base catalysts for biodiesel synthesis and suitability for industrial application. [ABSTRACT FROM AUTHOR]

The increased production of biodiesel as an alternative fuel involves the simultaneous growth in production of crude glycerol as its main by-product. Therefore, the feasibility and sustainability of biodiesel production requires the effective utilization of crude glycerol. This review describes various uses of crude glycerol as a potential green solvent for chemical reactions, a starting raw material for chemical and biochemical conversions into value-added chemicals, a substrate or co-substrate in microbial fermentations for synthesis of valuable chemicals and production of biogas and biohydrogen, as well as livestock feedstuff. Special attention is paid to various uses of crude glycerol in biodiesel production. [ABSTRACT FROM AUTHOR]

The viscosities of biodiesels of soybean and rapeseed biodiesels blended with mineral diesel fuel were measured at pressures of up to 200 MPa. Using a falling sinker-type viscometer, reproducible viscosity data were obtained based on the time taken for a sinker to descend a fixed distance down an enclosed tube under the influence of gravity. Measurements were taken using pressures corresponding to those of interest in automotive common rail diesel engines, and at temperatures between 25 and 80 °C. In all cases, the viscosity of the biodiesel blends were found to increase exponentially for which the blends were noted as being more viscous than pure mineral fuels. A pressure-freezing effect was not observed for the blends. [ABSTRACT FROM AUTHOR]

Currently, the catalytic efficiency and reusability of the solid base catalysts cannot meet the demand of industrial biodiesel production under low temperature. The purpose of this study is to define the kinetics of heterogeneous transesterification process that could be used for the prediction of the biodiesel synthesis at high temperature and pressure. The focus in this study was paid to recently reported data obtained with different catalysts used for biodiesel synthesis in a batch reactor at high temperatures. It was shown that three kinetic models, including: a) irreversible first order reaction, b) reaction with changeable order and c) resistances of mass transfer and chemical reaction at active sites of the catalyst, could be applied for predicting the effect of high temperature of the transesterification. The apparent reaction rate constant of the irreversible first order reaction was determined, as well as the parameters of the other two, more complicated kinetic models. The best agreement was obtained with the more complicated models and the mean relative percent deviation between calculated and experimentally determined triacylglycerols conversion for these kinetic models is between 3 and 10%. [ABSTRACT FROM AUTHOR]

The kinetic model, which was originally developed for sunflower oil methanolysis catalyzed by CaO·ZnO, was examined for several other calcium-based catalysts like neat CaO, quicklime and Ca(OH)2. This model including triacylglycerols mass transfer- and chemically-controlled regimes demonstrated a good agreement with the experimental data in terms of a high coefficient of determination (0.971±0.022) and acceptable mean relative percentage deviation (±15.9%). Hence, this model is recommended for modeling the kinetics of sunflower oil methanolysis over calcium-based catalysts under widely ranging reaction conditions. [ABSTRACT FROM AUTHOR]

The kinetics of heterogeneous methanolysis of sunflower oil was studied at 60 °C using mechanochemically synthesized CaO⋅ZnO as catalyst. The influence of agitation speed, catalyst amount, and methanol-to-oil molar ratio on the rate of reaction was analyzed. The rate of the process depends on the two resistances -- mass transfer of triglycerides to the catalyst surface and chemical reaction on the catalyst surface, which are defined as the values of the overall triglyceride volumetric mass transfer coefficient, kmt,TG, and the effective pseudo first-order reaction rate constant, k, respectively. These kinetic parameters actually determine the value of the apparent reaction rate constant, kapp, the time dependence of which is defined by the change of triglyceride (TG) conversion. A kinetic model is proposed and the model parameters are determined. [ABSTRACT FROM AUTHOR]

Ultrasound-assisted sunflower oil methanolysis catalyzed by KOH was studied to define a simple empirical kinetic model useful for reactor design without complex computation. It was assumed that the neutralization of free fatty acids and the saponification reactions were negligible. The methanolysis process rate was observed to be controlled by the mass transfer limitation in the initial heterogeneous regime and by the chemical reaction in the later pseudo-homogeneous regime. A model featuring irreversible second-order kinetics was established and used for simulation of the triacylglycerol conversion and the fatty acid methyl esters formation in the latter regime. Good agreement between the proposed model and the experimental data in the chemically controlled regime was found. [ABSTRACT FROM AUTHOR]