Synthesis Of Ionic Liquid Solid Acids And Their Catalytic Performances In Biodiesel Production

Nowadays,environmental and energy problems have become increasingly serious.Therefore,as a kind of green energy resource,biodiesel has attracted broad attention both inside and outside of China.The biodiesel is a kind of long-chain fatty acid which is prepared from the interesterification or esterification of animal and vegetable oil with short chain alcohol.Naturally,the research and development of the catalyst for biodiesel has become a hot issue which is of theoretical importance to the manufacture of biodiesel.The solid acid catalyst has many advantages such as high efficiency and ease of separation,which has been gradually applied to the manufacture of biodesel.For the convenience of anaphase separation,so as to realize the green production of biodesel,the preparation of different solid acid catalysts were discussed in this paper via different synthesis and grafting methodologies upon the basis of newly developed ionic liquid.1.With the importaton of SO3-and CF3SO3-,five ionic liquids were synthesized for the purpose of catalyzing the production of biodesel and comparing the catalic capacity therefrom.And the relative catalytic capacity was H2SO4>[Bsmim]CF3SO3>[Psmim]HSO4 ?[Bsmim]HSO4>[Bmim]HSO4>[Mim]HSO4.The result indicates that,[Bsmim]CF3SO3 has a relatively higher catalyzing capacity.The conditions the temperature T=60?,the dosage of catalist 10%,the molar ratio of methanol to oleic acid of 6:1,and the duration for reaction 3 hours given,the yield of biodiesel approaches 96.70%.2.A newly developed icidic ionic liquid with double bonds[SO3H(CH2)4VIm][CF3SO3]was synthesized on the basis of Vinylimidazole and 1,4-Butane sultone to inspect the influence of technological conditions on the catalytic process.The result shows that the conditions T=60?,the dosage of catalyst 5%,the molar ratio of methanol to oleic acid of 6:1,with the reaction duration 5 hours,the yield of biodiesel is up to 96.07%.Afterwards,the ionic liquid was recycled four times,with the yield staying around 95%.3.The divinyl benzene(DVB)taken as the monomer was adopted to synthesize the porous monodisperse poly(divinylbenzene)(PDVB)through precipitation polymerization.Through the graft copolymerization between pendent double bond on PDVB and the ionic liquid with double bond,the solid acidic catalyst was prepared to catalyze the oleic acid for the production of biodiesel.The result shows that with the given conditions T=90?,the dosage of catalyst 4%,the molar ratio of methanol to oleic acid of 20:1,and the duration for reaction 5 hours,the yield of biodiesel is 93.02%.Afterwards,the solid acidic catalyst was recycled four times,with the yield remaining stable.4.The magnetic mesoporuous silica microspheres taken as the substrate,the double bond ionic liquid was grafted to the magnetic microspheres to synthesize magnetic catalyst.The oleic acid taken as the material for the model,the magnetic solid acid was applied to the esterification between oleic acid and methyl alcohol,to produce biodiesel.The influence of technological conditions such as variation of temperature,dosage of catalyst,alcohol-oil ratio,and time consumed on the conversion rate of biodiesel were inspected.The result shows that under the conditions T=70?,the dosage of catalyst 8%,the alcohol-oil ratio 8:1,and the duration for reaction 6 hours,the yield of biodiesel is 88.43%.Afterwards,the magnetic catalyst was recycled four times,with the yield remaining stable.