Study On The Preparation Of Medical Grade Glycerol From The By-product Of Jatropha Biodiesel

Glycerol, also known as propenyl alcohol, was a colorless, transparent, viscous liquid, which widely existed in nature as the form of glyceride, and have been used as important raw materials in chemical industry. The process of producing biodiesel was accompanied by the formation of a large number of glycerol, the rational use of glycerol could effectively reduced the the production cost and improved the comprehensive market competitiveness of biodiesel. The object of this study was to prepare medicinal grade glycerol of high purity with glycerol, the byproduct of Jatropha Curcasl biodiesel, through the combination use of several resins.1. The decolorization and deashing properties of eight resins during refinement of glycerol were investigated. The results showed that HPD400 macroporous adsorption resin and strong basic anion-exchange resin717 gave the optimum decolorization effect and strong acid cation-exchange resin 732 had the optimum deashing effect.2. With decolorization rate, content of glycerol and recovery as investigated indexes, the optimum technological conditions of HPD400 macroporous adsorption resin and strong basic anion-exchange resin 717 were determined. The optimum technological conditions of HPD400 macroporous adsorption resin were as followed:the ratio of the load amount of crude glycerol to the mass of HPD400 macroporous adsorption resin was 1:8, the crude glycerol was diluted to make a final content of 70% of concentration and the adsorption time was 0.5h. After the purification process of HPD400 macroporous adsorption resin, the decolorization rate was 86.96%, content of glycerol was 97.42% and recovery was 98.77%. The glycerol fraction after the above processes was then loaded to strong basic anion-exchange resin 717 and the optimum technological conditions were as followed:the ratio of the load amount of the first purification glycerol to the mass of strong basic anion-exchange resin 717 was 1:8, the first purification glycerol was diluted to make a final content of 80% of concentration and the adsorption time was 1h. After the purification process of strong basic anion-exchange resin 717 decolorization rate was 98.07% and the absorbance of glycerol was up to the standard of analytical grade glycerol; The content of glycerol was 98.63% and recovery was 99.71%.3. With contents of sulfate ash, glycerol and recovery as investigated indexes, the optimum technological conditions of strong acid cation-exchange resin 732 were determined. The optimum technological conditions of strong acid cation-exchange resin 732 were as followed:the ratio of the load amount of the second purification glycerol to the mass of strong basic anion-exchange resin 732 was 1:10, the second purification glycerol was diluted to make a final content of 80% of concentration and the adsorption time was 1.5h. After the purification process with strong acid cation-exchange resin 732, the content of sulfate ash decreased below 0.01%, which was up to the standard of medicinal grade glycerol with superior quality; The content of glycerol was 99.65% and recovery was 99.62%.The results fully indicated that combination of HPD400 macroporous adsorption resin,strong basic anion-exchange resin 717 and strong acid cation-exchange resin 732 could be applied in the refinement of glycerol which produced as the byprodut of Jatropha Curcasl biodiesel, all the indicators of the purified glycerol were up to the GBT 13216-2008 standard for medicinal grade glycerol with superior quality.