Acid-Catalyzed Transesterification of Canola Oil to Biodiesel under Single- and Two-Phase Reaction Conditions

Abstract

Experiments were performed at ambient temperature to investigate the effects of mass transfer during the transesterification reaction of canola oil with methanol (MeOH) to form fatty acid methyl esters using a sulfuric acid (H2SO4) catalyst at a MeOH/oil molar ratio of 6:1. Experiments at ambient conditions resulted in reaction rates that were slow enough to permit the effects of mass transfer on the transesterification reaction to become more evident than at higher temperatures. For the two-phase experiments, it was postulated that the reaction occurred at the interface between the phases where the triglycerides (TG), MeOH, and H2SO4 were in contact with one another. The influence of mass transfer was investigated by (a) comparing a mixed versus quiescent two-phase reaction and (b) changing a two-phase reaction to a single-phase reaction through the addition of a solvent, tetrahydrofuran. The experiments revealed the presence of an induction period prior to the initiation of the reaction, and some of the factors influencing the induction period were identified.

Influence of Mass Transfer and Kinetics on Biodiesel Production Process

“…Lower mass transfer coefficients were reported for lower temperatures, since the mass transfer coefficients obtained by Frascari et al (2009) at 60 °C were greater than that obtained by Klofutar et al (2010) at 40 °C and 50 °C. The mass transfer coefficient (k c a) determined by Ataya et al (2007) was much lower than that reported in the other literature. In the case of Liu et al (2010), the apparent mass transfer coefficient value is not representative of the maximal coefficient that can be reached by reacting molecules before the reaction will occur, since the determination of mass transfer parameters was performed without acknowledging the experimental regime and the coefficient was consequentially unusually high.…”

“…Experiments were also performed by Ataya et al (2007) at ambient temperature to investigate the effects of mass transfer during the transesterification reaction of canola oil with methanol (CH 3 OH) to form fatty acid methyl esters using a sulfuric acid (H 2 SO 4 ) catalyst at a CH 3 OH/oil molar ratio of 6:1. Experiments at ambient conditions result in reaction rates that are slow enough to permit the effects of mass transfer on the transesterification reaction to become more evident than at higher temperatures.…”

“…Experiments at ambient conditions result in reaction rates that are slow enough to permit the effects of mass transfer on the transesterification reaction to become more evident than at higher temperatures. The influence of mass transfer was investigated by comparing a mixed versus quiescent two-phase reaction and changing a twophase reaction to a single-phase reaction through the addition of a solvent, tetrahydrofuran (Ataya et al, 2007). The presence of tetrahydrofuran minimizes the mass transfer problem normally encountered in heterogeneous systems (Soriano et al, 2009).…”

Effects of Temperature and Stirring on Mass Transfer to Maximize Biodiesel Production from Jatropha curcas Oil: A Mathematical Study

“…Two types of transesterification have been developed and analysed for biodiesel production using either chemical catalyst or biological catalyst [4][5][6][7]. There are ample research articles where alkaline transesterification for biodiesel production is investigated [8][9][10].…”

Production and Physicochemical Characterization of Methylic and Ethylic Biodiesel From Canola Oil

“…This property is justified by the fact of canola oil being rich in unsaturated fatty acids, Table 1. This oil has been used in several studies to test transesterification reactions conducted under adverse conditions, such as heterogeneous catalysts [19][20][21], in situ reactions [22], use of ultrasound [23] and alcohol in supercritical state [24], etc. In most studies, the type of alcohol employed was the methanol.…”