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Search Results: 1 - 10 of 1698 matches for " Donato Aranda "
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Process Temperature Profile and Rheological Properties of Greases from Vegetable Oils  [PDF]
Leticia M. Lazaro, Donato A. G. Aranda
Green and Sustainable Chemistry (GSC) , 2014, DOI: 10.4236/gsc.2014.41007
Abstract:

Greases are composed by lubricating oil dispersed in a thickener that can be a metal soap, polymers or clays. Grease production using vegetable oils is increasing due to biodegradability requirements. Since vegetable oils present a worse oxidation and hydrolysis stability than mineral oils, it is usually difficult to produce a neutral grease using them. Four greases were produced using soybean oil as lubricating oil and lithium 12-hydroxy- stearate as thickener. The maximum temperature of reaction ranged from 230°C to 120°C in a bench process and a reduction in the final product acidity was observed (from 8.2% acid to 0.05% alkaline). Traditional tests to evaluate thickener structure resistance like 10,000-time worked penetration, roll stability and dropping point were performed and results compared. In addition, rheological tests were performed and the results were also compared. Results indicate that it is possible to produce a quite neutral grease using vegetable oils with good thickener structure properties.

Biodiesel production by hydroesterification of microalgal biomass using heterogeneous catalyst  [PDF]
Yordanaka Reyes, Gisel Chenard, Donato Aranda, Cristiane Mesquita, Mariana Fortes, Rafael Jo?o, Leonardo Bacellar
Natural Science (NS) , 2012, DOI: 10.4236/ns.2012.410102
Abstract: This paper assesses the hydroesterification process for the production of Biodiesel from Monoraphidium contortum (MORF-1) microalgae biomass, as it is a sustainable alternative not only economically, but also environmentally and ecologically to replace petroleum diesel fuel. The Biodiesel studied in this work was obtained from fatty acid esterification, a product of microalgae and methanol biomass hydrolysis reaction. CBMM’s (HY-340) niobium oxide powder was used as catalyst. The reactions were carried out in a properly closed autoclave reactor (batch), where the reagents were mixed under constant stirring at 500 rpm for hydrolysis and esterification. The products generated were submitted to gas chromatography and oxidative stability analysis. The hydroesterification process showed itself to be a promising alternative to the conventional biodiesel production process (transesterification) as it favors the use of feedstocks with any acidity and moisture content and may be performed with acid catalyst, which favors high conversions in a small range of time (30 minutes).
Morphological and chemical aspects of Chlorella pyrenoidosa, Dunaliella tertiolecta, Isochrysis galbana and Tetraselmis gracilis microalgae  [PDF]
Cristiane Mesquita da Silva Gorg?nio, Donato Alexandre Gomes Aranda, S?nia Couri
Natural Science (NS) , 2013, DOI: 10.4236/ns.2013.57094
Abstract:

This study evaluates the growth and chemical composition of the following marine microalgae: Dunaliella tertiolecta, Isochrysis galbana, and Tetraselmis gracilis and the chemical composition of Chlorella pyrenoidosa. Microalgae can produce a number of compounds of high commercial value for the industry, mainly for the food industry. The growth kinetics, cell volume, pigments, carbohydrates, proteins, lipids, and fatty acid and amino acid composition were evaluated. I. galbana had the largest number of cells per mL-1 (107), concentration of carotenoids (6.33 μg·mL-1), and carbohydrates (34.32%). D. tertiolecta and T. gracilis had the highest cell volume (560.6 and 592.7 μm3, respectively), the highest amount of total dry biomass. D. tertiolecta

Enhancement of Cell Growth and Lipid Content of a Freshwater Microalga Scenedesmus sp. by Optimizing Nitrogen, Phosphorus and Vitamin Concentrations for Biodiesel Production  [PDF]
Neumara L. S. Hakalin, Amanda P. Paz, Donato A. G. Aranda, Lídia Maria P. Moraes
Natural Science (NS) , 2014, DOI: 10.4236/ns.2014.612095
Abstract:

The effects of nitrogen, phosphorus and vitamin on growth and lipid content of a freshwater microalgae Scenedesmus sp. were investigated under indoor conditions. Nitrogen, phosphorus and vitamin presented significant statistical effect on lipid content, and a maximum lipid content of 29.3% was obtained, corresponded to increases of 90% when compared to those obtained with the original nutrients medium. On the other hand, only nitrogen and phosphorus presented significant statistical effect on cell growth, achieving ash free dry biomass, algal density, and specific growth rate of 1.3 g·L-1, 1.5E+07 cells mL-1, and 0.62 d-1, respectively. By the use of the desirability function, it was possible to maximize the cell growth and lipid content simultaneously. The fatty acid composition of the microalgal lipid comprises over 80% of saturated and monounsaturated fatty acids. Thus, Scenedesmus sp. biomass could be used as suitable feedstock for biodiesel production.

Advances for Opaque PBR Internally Illuminated for Fiber Optic for Microalgae Production  [PDF]
Deusa A. M. P. da Ponte, Marcelo M. Werneck, Donato A. Aranda
Natural Science (NS) , 2016, DOI: 10.4236/ns.2016.88040
Abstract: The production of microalgae in laboratory systems is restricted almost exclusively since 500 mL to 20 liters tanks of transparent materials such as glass and plastic, under fluorescent lamps on shelves. In this work we developed a laboratory system which produced up to 50 liters of micro- algae cultivation with comparable productivity to the traditional system in the laboratory, with the potential to increase productivity scale and lower energy consumption per produced volume. The system is built with opaque plastic tank, and illuminated by Plastic Optics Fiber (POF) and LED. The quality of the biomass grown in the culture system on LED is comparable to the tradi- tional cultivation, with scale-up without increasing the occupied area, only with increased height of the tank. The productivity of the tank on LED to the strain Scenedesmus sp. with a phototrophic cultivation reached productivity of around 20 mgL1d1 and continuing studies may increase further.
Hydrolysis - Hydrogenation of soybean oil and tallow  [PDF]
Gisel Chenard Díaz, Rodolfo Salazar Perez, Neyda de la C. Om Tapanes, Donato Alexandre Gomes Aranda, Angel Almarales Arceo
Natural Science (NS) , 2011, DOI: 10.4236/ns.2011.37074
Abstract: Hydrolysis reactions are of major importance to the oleochemical industry in the production of fatty acid and their derivates. Hydrolysis of triglyceride from vegetable oil has been studied under various parameters such as: heterogeneous catalyst, temperature, reaction time and agitation speed. During the hydrolysis of soybean oil and tallow using nickel catalysts on alumina support was verified that the glycerol produced worked as hydrogen donor, allowing the hydrogenation of unsaturated fatty acids produced. Maximum conversion was achieved in 3 hours, catalysts 25% NiO/Al2O3, temperature of 250oC and 270oC and 250 rpm.
ZSM5 as a Potential Catalyst for Glycerol Pyrolysis  [PDF]
Margarida L. Castelló, Jo Dweck, Donato A. G. Aranda, Rosana C. L. Pereira, Manoel J. R. Guimar?es Neto
Journal of Sustainable Bioenergy Systems (JSBS) , 2014, DOI: 10.4236/jsbs.2014.41006
Abstract:

Glycerol is a substance known to humankind for many years now, and among other products, in which composition it is used, are the pharmaceutical, cosmetic, food, paints and varnishes REF _Ref382993082 \r \h [1]REF _Ref382993086 \r \h [6]. The abundance of its supply leads to search for new uses, whether as a plasticizer for biodegradable polymers REF _Ref382993096 \r \h [7], its transformation into other substances like propylene and derivatives or other hydrocarbons [8] [9], the production of hydrogen for energy purposes REF _Ref382993109 \r \h [10], or even direct burning, making glycerol a fuel for boilers, for example. The aim of this work was to investigate the action of the zeolite ZSM5 on glycerol fast pyrolysis at 600°C. The tests were done with a

Production of Hydrogen from Aqueous Phase Reforming of Glycerol: Economic Evaluation  [PDF]
Rodolfo Salazar Pérez, Mariana M. V. M. Souza, Neyda C. Om Tapanes, Gisel Chenard Diaz, Donato A. G. Aranda
Engineering (ENG) , 2014, DOI: 10.4236/eng.2014.61003
Abstract:

Glycerol is the main byproduct from the production of biodiesel by transesterification of vegetable oils, and approximately 10% of total biodiesel production volume corresponds to glycerol. The profitability of various chemical processes depends, in part, on the sale of byproducts, which enables a reduction in the production costs and consequently, in the product’s final price. Thus, it is necessary to look for alternatives to solve the problem of glycerol buildup, in order to avoid future environmental impacts and make biodiesel competitive in the growing market of biofuels. In this context, this study’s objective is the development of a low cost and environmental clean technology that allows the conversion of glycerin into a greater value product. In this paper, an economic evaluation of production hydrogen using Aqueous Phase Reforming (APR) was conducted. Firstly, we detailed the technical assumptions in the study. Reactions were performed in batch reformer of 10 liters of capacity, at the temperature of 250℃ and pressure of 38 atm. Finally, a sensitivity analysis was performed. The results from economic evaluation show that APR of glycerol, using nickel catalysts supported on alumina or zirconium oxide, is a promising and competitive technology for hydrogen production.

Biodiesel Production Based in Microalgae: A Biorefinery Approach  [PDF]
Lauren Espinosa González, Gisel Chenard Díaz, Donato Alexandre Gomes Aranda, Yordanka Reyes Cruz, Mariana Monteiro Fortes
Natural Science (NS) , 2015, DOI: 10.4236/ns.2015.77039
Abstract: It is of great knowledge nowadays that the use of fossil fuels is responsible for the emission of gases that intensify the greenhouse effect, which threatens the survival of the humankind. The gravity of this fact could be mitigated through the indirect use of solar energy for fuels derived from vegetable that can be planted and cultivated by the world of renewable and non-polisher. Microalgae play an important role in this regard, as they have promising characteristics as potential raw material for the production of biofuels, able to absorb large amounts of CO2. Chlorophyll organisms convert these simple substances in the atmosphere, absorbing sunlight into chemical energy stored, that is, compounds with high energy, biomass can also be used to obtain biocompounds human nutritional supplement and food animal, however, have been found an important number of difficulties to economically viable production like high cost of production of dry biomass and oil extraction. Here, we review the main approaches of biorefinery concept appearing as an alternative to achieve economic viability of the production of bio-diesel based on microalgae. The major points are the following: 1) use of re-residual water, 2) marketing of Carbon Credits, and 3) development of co-products resulting from high value added.
Primary Separation of Antioxidants (Unsaponifiables) the Wet Biomass Microalgae Chlamydomonas sp. and Production of the Biodiesel  [PDF]
Gisel Chenard Díaz, Yordanka Reyes Cruz, Mariana Monteiro Fortes, Carolina Vieira Viegas, René González Carliz, Nelson C. Furtado, Donato A. Gomes Aranda
Natural Science (NS) , 2014, DOI: 10.4236/ns.2014.615108
Abstract: This work studies the saponification which directs the wet biomass of algae Chlamydomonas sp. like a previous stage to production of biodiesel. This stage allows the obtainment of fatty acids to produce biodiesel, instead of the gross lipid fraction. In addition of the fatty acids, utilizing the same process one can also obtain the fraction unsaponifiable, these are soluble in apolar solvents and contain mainly carotenoids that can take action as antioxidants and photoprotectors, as they reduce the oxidation of unsaturated fatty acids. The saponification direct and extraction of fatty acids from biomass is faster and reduces the time and cost of operation. The separation of unsaponifiable matter from the biomass humid of microalgae Chlamydomonas sp., was held according to the method AOCS (Ca 6a-40), using extraction Liquid-liquid with hexane as solvent. Subsequently, phase hydroalcoholic or from soap, containing fatty acids, was acidified by addition of H2SO4 and the fatty acids were recovered by the addition of hexane. After acidulation of the soap, necessary for obtaining of the fatty acids was performed the stage of esterification for obtaining of biodiesel. The operating conditions were: molar ratio fatty acid:methanol (1:10), as catalyst 8% H2SO4 calculated in relation to the mass of fatty acid, 200 and reaction time of 90 minutes. The content of methyl esters was 96.8% determined by gas chromatography according to standard EN14103. The quality of biodiesel produced from wet biomass of Chlamydomonas sp. is according to the specification established by standard EN 14214 and RANP No. 14. For the identification of the composition the unsaponifiable fraction was used the method of High Performance Liquid Chromatography (HPLC). The composition of the material unsaponifiable found was of: Carotenoids total (0.76%); Lutein (0.45%); Zeaxanthin (0.07%); α-carotene (0.05%); β-carotene (0.11%); 13 cisβ-carotene (0.05%) and 9-cisβ-carotene (0.03%).
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