Study On Synthesis And Purification Of Glycerol Monolaurate

The objective of this study was to produce high-purity(≥90%) Glycerol Monolaurate (GML) through synthesis and purification.After comparing with other methods, GC analysis was choosed to determine GML in products. HMDS and TMCS were used as derivatization agent in GC analysis, while pyridine was used as solvent and catalyst. After derivatization, separation of samples containing GML could be achieved through a OV-17 glass column. Operating condition as follows: FID as detector, injection temperature at 320 ℃ ,detection temperature at 330℃ ,flow rate of N2 at 75ml/min and temperature program adopted. Temperature program was divided into three stages: first ascending from 120 to 240℃ at 10℃ /min; then ascending from 240 to 300℃ at 15℃ /min; And lastly staying at 300℃ for 3 minutes. The quantitative analysis of GML was carried out by internal standard method, with Tetradecanoic acid as internal standard. In this method, Linear range was 1.11-11.1 Img/ml and detection limit is 0.063mg/ml.After study on some important factors such as mole ratio of glycerol to Laurie acid, synthesis temperature and catalyst, the optimum condition of synthesis was determined. That was: synthesis temperature was 80℃ , mole ratio was 2:1, and 0.15% P-Toluene Sulphonic acid was served as catalyst.Because GML was thermal unstable and hard to distill, Molecular Distillation was used to purify crude product containing GML. In this paper, to determine the technique about Molecular Distillation of Glycerol Monolaurate, operating pressure, distillation temperature, condensation temperature and flow rate of distillation was studied in accordance with Mean Free Path Theory. The technique was made up of two stages: first glycerol and Laurie acid were distilled with operating pressure at 5Pa, distillation temperature at 90℃ , and condensation temperature at 60℃ ; then GML was distilled with operating pressure at 0.1 Pa, distillation temperature at 100℃ , and condensation temperature at 70℃ . high-purity(≥90%) GML was achieved by this technique.And a pilot-plant test was conducted. The result was encouraging: the content of GML was 90.36% and the recovery of GML was 81.32%.