Novel Solid Base Catalysts For Application On Biodiesel Production

Biodiesel production has attracted more and more interest from reasearchers, which isdue to its potential as an alternative fuel that offers a complementary strategy forsustainability. The development of solid catalysts has recently gained much attention in viewof simple preparation, low–cost and high catalytic activity.This paper was prepared by threenovel solid base catalysts and a series of ethylene glycol monomethyl ether fatty acidmonoester were prepared by the transesterification in which solid base catalyst of calcinedsodium silicate was used for the reaction.A novel ZnO/Ca（OH）₂/KF solid base catalyst was prepared by grinding method andapplied to biodiesel synthesis by transesterification of soybean oil. The effect of variousparameters such as KF molar amount, calcination temperature, the amount of catalyst, molarratio of methanol to oil, reaction temperature and time on the activity of catalyst wereinvestigated. And the catalyst was characterized by several techniques ofthermogravimetry/derivative thermogravimetry （TG/DTG）, X-ray diffraction （XRD）,Hammett indicator method and scanning electron microscopy （SEM）. The results indicatedthat the KF interacted with Ca（OH）₂and formed KCaF₃phase. The formed KCaF₃crystalphase was the main catalytic active component. Besides, the calcination temperate was greatinfluence on the basicity. A desired biodiesel yield of97.6%was obtained as catalyst amountof3%, methanol/oil of12:1and reaction time of1.5h at65oC.A nanosized Na₂SiO₃/CaO/KF catalyst were prepared by grinding method for thetransesterification of soybean oil to biodiesel. The catalyst was characterized by the Hammettindicator method, TG/DTA, XRD, FT-IR, SEM and TEM. The results showed that thecatalyst had flower micro-structure, small granules size （less than100nm）, and the newcrystal KCaF₃was formed in the catalysts. Under the optimal conditions, the biodiesel yieldcan reach97.0%.A KF/MMT catalyst was prepared by doping KF on calcined montmorillonite （MMT） andtested for transesterification of soybean oil with methanol to biodiesel. The obtained catalystwas characterized using techniques of X-ray diffraction （XRD）, Fourier transform infraredspectroscopy （FTIR）, Hammett indicator, nitrogen physisorption and scanning electronmicroscopy （SEM）. The effects of different reaction conditions on biodiesel yield wereinvestigated. The results indicated that the KF interacted with MMT and formed Al–O–Kcompounds was the main catalytic active component for the catalyst activity. The highest catalytic activity was obtained when methanol/oil molar ratio was12:1, the amount of catalystwas4wt%, reaction temperature was65oC and the reaction time was2.5h, the biodieselyield reached97.4%over the20%KF/MMT catalyst.A series of ethylene glycol monomethyl ether fatty acid monoester were prepared by thetransesterification of different fatty acid methyl ester （FAME） with ethylene glycolmonomethyl ether （EGME）. Solid base catalyst of calcined sodium silicate was used for thistransesterification. The effects of various parameters such as calcination temperature, theamount of catalyst, molar ratio of FAME to EGME, reaction temperature, and time on theactivity of the catalyst were optimized, as well as the recycling of catalyst was alsoinvestigated. Also, calcined sodium silicate was used for the further tests transesterifyingbiodiesel with EGME. The properties of calcined sodium silicate were characterized byseveral techniques of TG, XRD, Hammett indicator method, FT-IR and SEM. The resultsindicated that the calcined sodium silicate was effective for the transesterification reaction ofFAME with EGME. The maximum yield of ethylene glycol monomethyl ether fatty acidmonoester of above90.0%was obtained under the optimal reaction conditions. The catalystcan be reused for at least3cycles without loss of activity.