Research On Extraction Of Tocopherols From Sodd By Vacuum Rectification

There are many kinds of natural products in vegetable oil distillate deodorizer (VODD), such as tocopherols, phytosterols and squalene. Owing to their better biological and antioxidant activities, tocopherols are widely used in medicine, food, cosmetics and so on. It is of great economical value to extract tocopherols from VODD.Using soybean oil distillate deodorizer (SODD) as the raw material, separation of tocopherols by vacuum rectification was studied, with saponification and esterification reactions as the pretreatment. And the process simulation of separating tocopherols was also studied.It is necessary to do some pretreatments before the conduction of rectification. Through more complete saponification reaction, most glycerides in SODD are converted into free fatty acids (FFAs), and then esterification reaction is applied to convert FFAs into fatty acid methyl eaters (FAMEs). The effect of alcohol-oil ratio, soponification coefficient and reaction time on saponification efficiency was analyzed, and the effect of solid-oil ratio, esterification coefficient and reaction temperature on esterification efficiency was also analyzed. The best reaction conditions were found through optimization.ACDlabs Chemsketch software was used to calculate the thermophysical properties of components in SODD. The process simulations of vacuum simple distillation and rectification were conducted, and the effect of operating conditions on distillation result was also studied. The better operating conditions of distillation were found, with the increasing of tocopherols'content from 5% to 22%.The experiments of vacuum simple distillation and rectification were conducted. It was found that the recovery of tocopherols was improved through reflux technology. Under the best operating conditions the content of tocopherols can reach 25% through vacuum rectification, and the final content can reach to 40% after the subsequent solvent extraction.