Navegando por Assunto "Physicochemical process"

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Acesso aberto (Open Access)
Craqueamento termocatalítico do óleo de buriti (Mauritia flexuosa L.), óleo de palma (Elaeis guineensis) e sabões do óleo de buriti (Mauritia flexuosa L)
(Universidade Federal do Pará, 2011-06-30) SILVA, Marcilene Silva da; MACHADO, Nelio Teixeira; http://lattes.cnpq.br/5698208558551065; BORGES, Luiz Eduardo Pizarro; http://lattes.cnpq.br/8756886156388456
The present work aims to investigate the Thermocatalytic Cracking Process of the Buriti Oil ( L.), Palm Oil (Elaeis guineensis) and burit oil soap, considering the transformation of vegetable oils and soaps using the thermocatalytic cracking in biofuels, using Na2CO3 (Sodium Carbonate), CaCO3 (Calcium Carbonate), CaO (Calcium Oxide) and Acidic Zeolites (HZSM-5) as catalysts and temperatures of 420, 450 and 480 ° C. The fruit of Buriti (Mauritia flexuosa L) was collected and extracted from the pulp oil, and then this oil was characterized in relation to the Acidity Index, Saponification Number, Viscosity, Density, Refractive Index and CHN analysis. In preliminary tests it was used the refined and neutralized palm oil, so they were not characterized. Buriti soap was prepared in the laboratory with potassium hydroxide and sodium hydroxide and stored for thermal pyrolysis. The catalysts were also characterized in relation to Infrared, Nuclear Magnetic Resonance of 29Si and 27Al, XRay Diffraction, thermal analysis, chemical analysis and TPD of ammonia. In the process of thermocatalytic cracking the liquid products produced were analyzed regarding the parameters: yield, acidity index, infrared spectrum, NMR and CHN analysis and then were characterized in relation to density and kinematic viscosity. However, regarding the level of acidity of the liquid products, only basic catalysts produced cracked with acceptable values for use as fuel. From the results it was verified the efficiency of catalysts in which the sodium carbonate catalyst gave products with low acidity and good characteristics for use as fuel.
Acesso aberto (Open Access)
Estudo das variáveis operacionais dos processos de separação na produção de biodiesel, a partir do óleo de palma bruto (Elaeis guineensis, Jacq) em escala de laboratório
(Universidade Federal do Pará, 2013-11-14) CASTRO, Douglas Alberto Rocha de; ARAUJO, Marilena Emmi; http://lattes.cnpq.br/8983914018546682; MACHADO, Nelio Teixeira; http://lattes.cnpq.br/5698208558551065
In this work, the operational variables involved on the separation processes applied on the pre-treatment of crude palm oil (guineensis Elaeis, jacq) , as well as on the purification of biodiesel, produced by transesterification with ethanol and using NaOH as catalyst, have been investigated systematically in laboratory scale. In the pre-treatment step, the processes of Filtration and Decantation have been investigated, being the filtration of the product, carried out by neutralization at 40ºC, 50ºC and 60ºC, whereas by Decantation, it had been evaluated the temperatures of 40ºC and 60ºC in 120 minutes. After that, it was investigated the influence of the time of decantation by 60, 90 and 120 minutes on the water washing process of the neutralized oil at 40ºC and 60ºC, followed by dehydration under vacuum at 80ºC, having been investigated in this stage the influence of the pressure. After the production of biodiesel, it had been evaluated the process of Evaporation of ethanol in excess, whereas in a first step, it had been investigated the temperatures of 70 and 80 ºC, maintaining the evaporation time constant and equal to 20 minutes, within the interval of 613,30 and 80,0 mbar, and in a second step, it had been investigated the system pressures of 480,00 and 346,60 mbar. After that, it had been investigated the influence of time on the decantation process of the glycerol rich phase at 70ºC, for times of 60, 120 and 180 minutes. Afterwards, the ester rich phase has been submitted to water washing at 70ºC, for the times of 60, 90 and 120 minutes. After that, it was evaluated the efficiency of the process of centrifugation of the mixture biodiesel and glycerol at 60 and 70ºC, 2000 rpm, and a time of 15 minutes. After that, the ester rich phase has been washed with water at 60 and 70ºC, being the separation carried out by centrifugation at 60 and 70ºC. The ester rich phases, obtained by decantation and centrifugation have been submitted to dehydration under vacuum, and characterized according to the specifications of the ANP. In accordance with the experimental results, on the basis of the quality of neutral oil and process yield, it has been observed that the Filtration at 50ºC produced the best results. In relation to the evaporation of ethanol, the higher ethanol recovery was obtained by 80ºC and 346.6 mbar. In relation the separation of ester and glycerol rich phases, the process of centrifugation at 60ºC produced a biodiesel of better quality and higher yield. It was still observed, the necessity of one second step of centrifugation to minimize the losses of biodiesel in the rich phase in glycerol.
Acesso aberto (Open Access)
Obtenção e caracterização de carvão ativado de caroço de buriti (Mauritia flexuosa L. f.) para avaliar o processo de adsorção de uma solução de Cu (II)
(Universidade Federal do Pará, 2013-09-30) PINTO, Marcos Vinicios de Souza; SILVA, Denilson Luz da; http://lattes.cnpq.br/4241759369873376
Buriti core carbon (CCB) was produced from the reject of artisanal production of its fruit for the extraction of oil, heated to 400ºC. Then, the CCB was activated at temperatures of 800ºC and 900ºC. Adsorption tests were performed to evaluate the discharge of these activation temperatures in the adsorption of a solution of copper (II) to a known initial concentration of 50 mg/L. After having examined the results, it was decided by the activation of coal to 900ºC. The activated carbon of the buriti core (CACB) to 900ºC was characterized according to commercial properties such as specific area, porosimetry, apparent and real densities, porosity of a bed fix, scanning electron microscopy, ash content, pH, moisture, fixed carbon and acid surface functional groups present in the CACB. The results showed a higher removal efficiency of copper (II) to the diameter D < 0.595 mm, for the contact time of 300 minutes, for the pH of 4.01 and the initial concentrations of copper (II) 50 and 80 mg/L. Mathematical models of Langmuir and Freundlich were applied to the data of adsorption equilibrium. The mathematical model of Langmuir was the best fit to the data of balance. The Langmuir’s mathematical model was the best fit to the data of balance. According to data from the kinetic equilibrium, it was observed that from the contact time of 15 minutes all the equilibrium concentrations were below the allowed maximum of 1,0 mg/L under the law CONAMA nº 357/2005 for release effluent into aqueous environments. The experimental results obtained are indicative that it is possible to remove copper (II) from industrial effluent using CACB activated physically at 900ºC for a period of 60 minutes.
Acesso aberto (Open Access)
Síntese e caracterização de analcina obtida a partir de rejeito caulim com aplicação em adsorção
(Universidade Federal do Pará, 2006-12-19) CORREA, Edinelson Saldanha; NEVES, Roberto de Freitas; http://lattes.cnpq.br/9559386620588673
In this work from kaolin processing industries from Ipixuna-PA were used in order to synthesi analcime derived zeolite as predominant crystalline phase though the hydrothermal process. The sample was converted into metakaolinite by calcinations at 700°C during 4 hours. From sample this metakaolinite a reacting mixture consisting of diatomite and sodium hydroxide was prepared. In order to determine of ideal conditions for analcime synthesis, a number of process variables were measured such as sodium availability, silicon ratio, nature of the silica source, pH of the reacting mixture, and auto clave residence time. Some important properties of the adsorbent where measured as well, such as thermal stability in the presence of acids hydrogen desorption kinetics, the trends of the adsorption isotherms as such as selectivity for copper, cadmium, zinc and nickel ions. Analcime synthesis from kaolin processing wastes was feasible. A displacement in the (h, k, l) planes was observed at 400 °C and was maintained up to 600°C, caused by the withdrawal of oxygen in positions 1/8 in analcime, shrinking the unit cell and in active channels and sites of zeolite, affecting its adsorption capacity.