Phospholipid transesterification in sub-/super-critical methanol with the presence of free fatty acids

摘要: Abstract Phospholipids and free fatty acids (FFA), along with triglycerides, are naturally formed constituents in unrefined vegetable oils other plant lipids. Presence of phospholipids FFA such can cause processing difficulties, as saponification decrease catalytic efficiency, thus lead to an adverse process efficiency the transesterification for biodiesel production. This phenomenon was also observed our previous study on converting microalgal lipids acid methyl esters (FAME) via situ transesterification. aimed at further exploring investigating effects presence conditions production from sub- and/or super-critical methanol (SubCM/SCM). Experiments were carried out a batch reactor SubCM/SCM under various without addition catalysts. Pure chemicals lecithin stearic used model compounds FFA, respectively. The product yield (FAME mol%) after transesterification, affected by different conditions, selected respond factor determine efficiency. Experimental results showed that be converted into FAME process. Transesterification is largely interactive effect operating temperature reaction time. increase proportional increases maximum 68.1 mol% achieved 250 °C 120 min FFA. started level off once system reached SCM state. When held 290 °C 30 min, dropped 33.6 mol%. Another enhances considerably lipid conversion. revealed highest 93.9 mol% catalysts However, enhancement became less significant when operated longer period time than 120 min.