000			02416nab a2200205 4500
005			20260520000837.0
008			260224s2009 xxu
245	0	0	_aBiodiesel production from castor oil _bOptimization of alkaline ethanolysis
260			_a _b _cnov./dic. 2009
270			_a08/06/2010 ; 08/06/2010
300			_a6 p. ; 5636-5642
520			_aTranscripción del resumen del autor. This work presents the biodiesel production from castor oil with bioethanol from sugar cane (also called here ethanol) in presence of sodium ethoxide and sodium hydroxide as catalysts. The studied variables were reaction temperature, catalyst concentration, and ethanol:castor oil molar ratio. The experimental design was used in the optimization process because this methodology permitted a careful evaluation of the process variables. A model describing the biodiesel conversion in terms of reaction temperature, molar ratio ethanol:castor oil was identified. The experimental design shows the catalyst concentration as the most important variable and the model obtained predicts the ethyl ester concentration as function of the reaction temperature, the ethanol:castor oil molar ratio and the catalyst concentration. A conversion of 99%wt of ethyl ester was obtained at 30 °C, with mechanic stirrer, 1 %wt of sodium ethoxyde, ethanol:castor oil molar ratio of 16:1 and at 30 min of reaction. The kinetic study of the transesterification reaction was carried out, and the apparatus used for the experiment was a 1 L jacketed reactor, equipped with a variable speed agitator. The study was based on the overall transesterification reaction. In the kinetic study, the temperature of the reactor was controlled and maintained at 30, 40, 50, and 70 °C. The results from the experiments demonstrate that the kinetically controlled region follows a first-order mechanism for the forward reaction. The castor oil molecular weight was determined using the vapor pressure osmometry technique (VPO). The results showed that VPO technique is a robust alternative methodology for determining vegetable oil molecular weight presenting lower cost than gas chromatography analysis (GC).
581			_a6
773	0		_tEnergy & fuels _g23
942			_cARTICULO
100	1		_aNivea de Lima da Silva _942308
100	1		_aBatistella, César Benedito _942309
100	1		_aFilho, Rubens Maciel _942310
999			_c170800 _d170800