Biodiesel Byproduct Glycerol Dehydration To Propylene Glycol

With coal, oil and other fossil energy reserves dwindling and increasingly serious pollution, wind, people pay more attention at solar, biomass and other clean renewable energy.In particular, its low-emission bio-diesel, and can be directly applied to existing diesel engines and favored. But the more in-depth study of bio-diesel and bio-diesel for the mass production of its by-product - glycerol production (by 10% of biodiesel production calculation) also increased dramatically. Large accumulation of glycerol has restricted the development of bio-diesel energy bottleneck. Therefore, the development of such efficient use of glycerin become one of the current hot topics.In this thesis, the presence of the glycerol dehydration reaction products distribution in high-temperature water. Focused on exploring the presence of water at high temperature, dehydration reaction of glycerol through the possibility of propylene glycol. Found:1) the presence of water at high temperature conditions, the glycerol dehydration can direct synthesis of propylene glycol. The phenomenon was found that the production of propylene glycol will be a new process route.2)The maximum effective yield of propylene glycol 89.31% at a single reaction, the corresponding experimental conditions: high temperature water 280℃, 5% wt In(CF3SO3)3, 5% wt glycerol in Aqueous Solution 7 ~ 8min.3) When the Department of material containing copper as a catalyst for the reaction, the yield of propylene glycol and the catalyst for the Law of Cu(CF3SO3)2>CuSO4>CuNO3>CuO/Cr2O3. Found that ion type and state on the yield of propylene glycol has an important influence; further study found that not only the acid radical influence on the reaction type, the type of cation has an important impact on the reaction, that is In(CF3SO3)3 better catalytic effect of Cu(CF3SO3)2.4) the content of the catalyst in the reaction affects the reaction conversion and selectivity. General catalyst content increased, the reaction conversion and propylene selectivity also increased, but too much catalyst content, reaction time is too long, will increase the incidence of side effects, so that further decomposition of propylene glycol. Therefore, the catalyst content should be optimized according to the reaction time. 5) Reaction temperature and reaction time also affects the reaction conversion and selectivity. The reaction temperature is too high, there is serious coking phenomenon, reducing the conversion of propylene glycol. Reaction time is too long to increase the incidence of side effects, also make propylene glycol decomposition.Phenomena and the results of these studies for the comprehensive utilization of glycerol and propylene glycol to explore new production processes provide the basis for development.