Extraction Of Natural Vitamin E From Corn Oil Deodorizer Distillate

The corn oil deodorizer distillate is by-product in the process of oil refining,containing natural Vitamin E and a good resourse for VE.The subject of raw material is corn oil deodorizer distillate,carried out a serious of experiments about esterification of fatty acid in deodorizer distillate,which was catalyzed by the immobilized lipase and tert-butyl alcohol instead of traditional molecular sieve.Then the phytosterol and insoluble impurity were removed by crystallization and the crude VE was obtained,followed to purify the Vitamin E by ion exchange.Finally,the structure of prepared Vitamin E was analyzed.The following is the mainly conclusions:According to the National Standard,the physicochemical properties of raw material have been analyzed as follows:water 0.44%,insoluble impurity 0.91%,viscosity 8.50 mPa · s,acid value 110.24 mgKOH/g,saponificaton value 141.30 mgKOH/g,peroxide value 1.85 meq/kg.Free fat acid content and glyceride content respectively have been calculated according to acid value and saponificaton value,the percentage content of free fat acid 55.51%and the percentage content of glyceride 16.95%-20.05%.The optimal reaction conditions of two kinds of esterification had been studied.The optimal reaction conditions of methyl esterification were determined under followings:methyl alcohol mixture ratio to 1.0:1,lipase dosage was 14mg/g,tert-butyl alcohol dosage was 6%,water bath heating at 55 ? for 15h.The result showed that methyl esterification rate was up to 97.26%,retention rate of Vitamin E was 96.36%.Lipase coule be used repeatedly for 7 times.The optimal reaction conditions of ethyl esterification were determined under followings:ethyl alcohol mixture ratio to 0.8:1,lipase dosage was 14mg/g,tert-butyl alcohol dosage was 8%,heating in a water bath at 60? for 15h.The result showed that ethyl esterification rate was up to 96.88%,retention rate of Vitamin E was 96.74%.Lipase could be used repeatedly for 10 times.Esterification product was removed phytosterols and insoluble impurities by crystallization,the crystals were filtered off through three times cooling and crystallization.The crude tocopherol was obtained with 41.66%VE content in samples.The optimal reaction conditions of purification VE by the strongly basic anion exchange resin,which ethanol as solvent and acetic acid-ethanol solution as the eluent.The single factor experiments was considered through the initial concentration of VE,eluent flow rate and the concentration of eluate,then by using the Box-Behnken central composite design and response surface method analysis of the establishment of the second regression model.The optimal separation conditions of the extraction process:the initial concentration of VE 100mg/ml,elution flow rate is 3ml/min,the concentration of eluate 5.98%.Under this condition,the purity and yield of VE was 87.78%and 75.72%.Finally,the refined Vitamin E was identified by TLC and HPLC method.