Sythesis Of Sulfonic Acid Functionalized Solid Acid Catalysts And Application In Biodiesel Reaction

As one of renewable energy resources helping the whole world survive the energy crisis,biodiesel becomes more compelling than ever for it can be derived from bio-grease(plant oil and animal fat) and free fatty acids,both of which finally keep carbon balance with automobile exhaust going through the photosynthesis of plants. biodiesel is synthesized conventionally via the base-catalyzed transesterification of refined greases that contains triglyceride mainly.However,the recovered waste greases are considered as more appropriate feedstock for the humanized energy allocation and maximized commercial profits in the sustainable biodiesel production. The acid catalyst is thus adopted instead of the base since the waste greases store triglyceride for the most part besides a relatively large amount of free fatty acid as a result of the hydrolysis in the course of using or preserving.In this thesis,I have designed two parts of the research:First,we synthesized Li-Al hydrotalcite as catalyst to the transesterification of refined oil and XRD,SEM were used to characterized for its structure.Second,sulfonated carbon-silica solid acid composite(C/CS-SO₃H) and sulfonated mesopores polymer(FDU-15-SO₃H) were sythesized as acid catalysts for esterification of palm acid and transesterification of soybean oil and waste oil.XRD, SEM,TEM,nitrogen gas adsorption,TG,IR and acid-base titration were utilized for characterization of the catalysts.The proper condition of sulfonation and the biodiesel production was investigated.Both of the solid acid behave a superior activity over the the transesterification of SBO and the esterification of palmitic acid with methanol. Especially the catalyst FDU-15-SO₃H,due to its remarkable properties of stable organic structure,large surface area,unique mesopore channel and abundant acid amount,it shows a bright application in the biodiesel synthesis from feed stocks with high content of free fatty acids.