Study On Poly Ionic Liquid Solid Base For Biodiesel Production

Biodiesel is a kind of renewable energy,which is of great significance to solve the problem of fossil fuel crisis and environment degradation.The phonomenon of leaching and deactivation caused by carbon dioxide and water in air occurred when the traditional solid base catalyst was used to product the biodiesel.In order to solve the problem,based on the designability of PIL,a novel superhydrophobic porous poly?ionic liquid??PIL?solid base catalyst was prepared by radical polymerization with a subsequent anion exchange providing alkali catalysis.In addition,the catalytic performance of the PIL catalyst was evaluated by the transesterification of soybean oil with methanol to produce biodiesel.To begin with,the physical and chemical properties of refined soybean oil were investigated.Then,the PIL catalyst was synthesized by two-step reaction including radical polymerization and anion exchange.Fourier transform infrared?FT-IR?spectroscopy,X-ray photoelectron spectroscopy?XPS?spectra,scanning electron microscope?SEM?,transmission electron microscopy?TEM?,powder X-ray diffraction?XRD?,nitrogen isotherms adsorption-desorption,thermogravimetric analyses?TG?and static water contact angle measurement were utilized to characterize the as-prepared PIL catalyst.When the homemade PIL catalyst was used to produce biodiesel using soybean oil and methanol as reaction material,the effects of the ratio of methanol to soybean oil,the catalyst dosage and the reaction time on the yield of biodiesel were systemically investigated,and the optimum reaction conditions was obtained by three-level and three-factorial central composite design?CCD?of response surface methodology?RSM?.The result shown that the product yield reached up to 96.32%under the optimum conditions:21.9 for the molar ratio of methanol to oil,9.15wt.%for catalyst amount and the 9.33 h for reaction time.Furthermore,the catalyst was reused for five cycles without significant decrease in activity,and the yield of biodiesel was still remain 85%and without metal ion leaching,which indicated that the homemade PIL catalyst posessed a favor reusability.What's more,the property of the prepared biodiesel was within the standard of EN14214 and ASTM D6751.Kinetics studies at optimal conditions illustrated that when the reaction was assumed to the pseudo first order reaction,the reaction rate constant K was 0.2347,activation energy Ea was 69.95 KJ/mol,Pre-exponential factors was 1.78 x 10¹00 h^-1.And the dynamic model was-r=?-dC_A?/?dt?=kC_AC_B³=0.2317C_A=1.78×10¹⁰e-?69.95?/?RT?C_....