Ethanolysis of camelina oil under supercritical condition with hexane as a co-solvent

Continuous catalyst-free production of esters from Jatropha curcas L. oil under supercritical ethanol

“…As can be seen in Figure 6(a), the addition of n-hexane as the cosolvent in the reaction medium improves process efficiency, probably due to the fact that introduction of this co-solvent increases the mutual solubility between ethanol and triglycerides, reducing mass transfer limitations, increasing the reaction rates, since with 42 min of residence time about 68 wt% FAEE yield was obtained without cosolvent and 78.4 wt% FAEE yield was obtained with a cosolvent:oil mass ratio of 20 wt%. Muppaneni et al (2012) evaluated the ethanolysis of camelina oil with n-hexane as the cosolvent and reported that the addition of this cosolvent played a vital role in reducing the severity of critical operation parameters and maximized the biodiesel yields. In fact, these authors showed that the ethyl ester yield was 44.6% without hexane, whereas the yield increased to 65.33% with a 0.05 (v/v) cosolvent:oil ratio at 568 K, 10 MPa, an oil:ethanol molar ratio of 1:25 and 20 min of reaction.…”

Biodiesel production through non-catalytic supercritical transesterification: current state and perspectives

“…As co-solvents in supercritical transesterification, it has been suggested to use non-polar compressed gases, for example, carbon dioxide, methane, ethane, propane, n-butane and their mixtures . Some studies have also reported the use of heptane/hexane (Imahara et al, 2009;Tan et al, 2010;Muppaneni et al, 2012;Jiang and Tan, 2012) and cyclohexane, dimethyl ether, ether and toluene as co-solvent (Jiang and Tan, 2012). Cao et al (2005) and Han et al (2005) studied the potential use of carbon dioxide and propane as cosolvents in batch mode ester production.…”

“…The use of n-heptane as cosolvent was reported by Tan et al (2010) and the results showed that the addition of a small amount (0.2 molar ratio) of n-heptane to methanol had a significant influence on the reaction yield of palm oil with supercritical methanol. Muppaneni et al (2012) showed the influence of the addition of n-hexane in the ethanolysis of camelina oil and found that the maximum yield was obtained with the addition of 0.2 n-hexane to oil volume ratio.…”

Sub and Supercritical Fluid Technologies for the Production of Renewable (Bio) Transportation Fuels

“…This process does not require any pre-treatment of the feed stock regardless of its fatty acid composition and profile. In non-catalytic supercritical transesterification the oil to alcohol ration varies between 1:40-45 depending upon the feed stocks fatty acid profile, 290-350 o C temperature, and reaction pressure above saturation pressure [5,10]. Introduction of cosolvent into the reaction mixture decreases the critical point of alcohol, increases the mutual solubility of the oil and alcohol at lower reaction temperatures and accelerates the reaction rate under supercritical alcohol conditions [11].…”