The Development And Application Of Glycerin From By-products Of Biodiesel

At present, the product technology and raw material selection of biodiesel are inactive study and its application on a certain degree both in and abroad. The prospectof biodiesel becomes broader with the increase of its Competitiveness andgovernment support as well as the bio-dieselization of vehicle worldwide. By 2010,the annual production of bio-diesel will reach 100 million tons in china; it will reach19 million tons in 2010. As a renewable biomass energy resource, the developmentprospect for bio-diesel is extremely extensive, and the market competitiveness keepsrising. But the main problem ofbio-diesel is that the cost is too high.Researchers tryto solve this problem from the area of raw materials and catalysts, but they have notgot an ideal solution.Although we are studying and producing bio-diesel actively, the research anddevelopment of glycerin which is its by-product is still far from enough. Theby-product is at a dramatic 10％increase, a lot of by-products are used to feed pigs. Ifa large number of the by-products use unreasonable, it will not only lead to a waste ofresources, but also may pollutes the environment. So from the perspective ofresearching glycerin, the development of high-grade glycerol and various applicationsof glycerol mean not only a reduction to the cost of bio-diesel and governmentbio-diesel production subsidies, but also can ease the import pressure of high-purityglycerin and important medical and chemical products, which plays an obvious rolein promoting the development China's economic. The momentum is unstoppable.Therefore, the refining and comprehensive of glycerin is a new issue and challenge toscientific and technological workers.Preparation of Bio-diesel-products glycerol, unglue the Chinese tallow treeseed oil in the phosphate content was 0.14％, water content was 4.1％,temperaturewas 70℃; Refine it In-alkali content was 0.1％, the concentration of alkali 120Be(8.07). temperature 65℃; produced bio-diesel under the condition of Alcohol to oil inmolar ratio was 6:1, 1％sodium hydroxide catalyst, temperature was 65℃, 45 to60min through esterification. Kept to separate the lower layer liquid after the reaction. In this paper, I provided reliable data and Process for the synthesis of high purityMonostearin with bio-diesel-products glycerol: dilute the lower reaction liquid with20％water in weight, and then added sulfuric acid was 50％the concentration toneutral it, then made centrifugal separation; isolate glycerol from the middle, madeatmospheric distillation to get rough glycerol. Improved the process with quadraticregression orthogonal rotating design. Stirring crude glycerol and boric acid of sameMoore in 100℃for 2.5 hours, then react with stearic acid at a molar ratio was 2.8, thetemperature was 140℃, for 1.8h, glyceryl monostearate was 97.97％we can gotwhich from ethanol extraction recrystallization, applied Fourier transform infraredspectroscopy to analyse.In addition, we also discussed the process of refining crude glycerol and thepossibility of synthesis of Triacetin from crude glycerin. If we crude glycerol toproduce Triacetin, the bleaching process could not be achieved. Therefore, we usedrefined glycerin to produce Triacetin. We provided reliable data and process forindustrial production: adjust pH value at about 4.5-5.5 concentration of sulfuric acid.Separate glycerin from the middle crude glycerin through centrifugal separation.Bleached the crude glycerol with activated carbon filtration, then used macro porousresined and waked acid cation macro porous strong base anion resin to bleach, thenafter vacuum distillation dehydration we got colorless and transparent, viscosityglycerol at the purity was 99.6％.The Moore ratio of acetic acid and glycerol was 4.0,the amount of catalyst to p-toluenesulfonic acid was 1.5g, and the reaction time was2.0h, dehydrating agent 10ml amount of toluene. Kept micro boiling state, tappedsome time back. After the reaction, cool the reaction solution to room temperature,saturated with sodium carbonate. Wash it with the same volume of saturated saltwater 2-3 times, so that it was neutral. The distillation temperature we Collected at258～260℃. After drying, we got colorless and transparent oily liquid, content of upto 93.26％.