Synthesis Of Medium Chainn Triglycerids And Purification

Medium chain triglycerides(MCT) is comprised of caprylic and/or capric in the sameglycerol backbone, Because of its unique metabolic characteristics and physiological function,it is widely used in food, medicine, chemical industry, etc. Both lipozyme and acidic ionicliquid catalyst were used for the esterification MCFA with glycerol for the preparation ofMCT, the influence of different factors towards esterification rate and TG yield were studiedin the esterification process for the production of MCT. Through the process, the optimumreaction conditions of the production of MCT were obtained finallyal.The catalysis effect of four commercial lipases were studied in solvent-free system, thebest was Novozyme435. Used Novozyme435as catalyst, The optimal process condition ofproduced MCT was obtained by one-factor experiment and orthogonal experiment as follows:reaction temperament90℃, enzyme load5%(rasis on the mass of fatty acid), substrate molarratio (radio of fatty acid to glycerol)3:1, and reaction time16h. Under the optimal condition,the esterification rate and TG yield was98.30%and92.10%, respectively. After separationand purification, the TG yield was97.65%.The two kinds of acidic ionic liquid [Spmim][HSO4] and [Spmim][PTSA] weresynthesised by two-step method, and were characterized by IR and mass spectrometry.Experiment showed that the products were the target production. The results showed thatdecomposition temperature of two kinds of ionic liquids both at about300℃; Acidity was2.67and2.55, respectively.Compared of the two kinds of acidic ionic liquids catalytic esterification effect, under thesame conditions, the high acidity of [Spmim] HSO4were better. Used [Spmim][HSO4] ascatalyst, The optimal process condition of produced MCT was obtained by one-factorexperient and respone surface methodology(RSM) experiment as follows: reactiontemperament160℃, reaction time16h, catalyst dosage0.74%(rasis on the mass of fatty acidand glycerol) and substrate molar ratio3.2:1. Under the optimal condition, the esterificationrate and TG yield was95.48%and92.90%, respectively. After separation and purification,the TG yield was96.15%. The acidic ionic liquid [Spmim][HSO4] was immobilized by the methods of gel-sol. Theproduct was white power, immobilized ionic liquid was more convenient when weighing andrecycling, and the catalytic activity was almost the same as before. Under the optimumconditions in this chapter, the esterification rate and TG yield was94.96%and92.57%,respectively.Differential Scanning Calorimetry (DSC) was used to study the non-isothermalcrystallization kinetics of MCT, the results indicated that crystallization exothermic peak ofTG was single peak. Non-isothermal crystallization activation energy of MCT was obtainedby the Takhor equation and Kissinger equation, the activation energy was-9.56kJ/mol and-9.89kJ/mol, respectively. And the mechanism of non-isothermal crystallization kinetics ofMCT was investigated using the Mo. method, the a value crystallization peak obtained by Mo.method was from3.25to3.58and the F(T) was from2.65to3.49.