NaY-based Solid Base Catalyzed Transesterification Of Castor Oil To Prepare Biodiesel

With the global energy shortage and the worsening of the environment,controlling automobile exhaust emissions of automobiles and protecting the natural environment on which human beings depend has become a top priority for human society.From the perspective of protecting the environment and resource strategy,all countries in the world are actively exploring the development of clean and safe renewable energy.Biodiesel,namely the fatty acid methyl ester?FAME?,is mainly obtained by transesterification of animal and vegetable oils with short-chain alcohols.It has many advantages such as non-toxicity,biodegradability and renewability.It is a typical green energy source,also known as“Sunshine fuel”is an ideal substitute for traditional petrochemical diesel.Castor oil is one of the world's four major non-edible oils.Its oil content is 48.1%-52.4%.China's castor oil production is the third in the world.It is an ideal raw material for biodiesel production in line with China's national conditions.1.The physicochemical properties of castor oil were tested and analyzed.The main physicochemical properties of castor oil were as follows:acid value 0.9 mg?KOH?/g,saponification value 181.5 mg?KOH?/g,average molecular weight 931.2,water content0.1%.2.The mesoporous spherical La₂O₃/NaY solid base catalysts were prepared by physical mixing method through granulator,and its catalytic performance in the transesterification of castor oil with ethanol to biodiesel was studied.The La₂O₃/NaY solid base catalysts were characterized by X-ray diffraction?XRD?,Scanning electron microscope energy spectrometer?SEM-EDS?and N₂ adsorption-desorption?BET?.The results showed that the catalyst?S-La₂O₃/NaY-800?had good specific surface area,alkaline strength and crushing strength after calcination at 800 ^oC.The addition of surfactant has a positive effect on the La₂O₃ dispersion and pore size of zeolite NaY.Subsequently,the parameters of the transesterification reaction of castor oil based on La₂O₃/NaY solid base were optimized by single factor analysis.Under the optimization conditions of catalyst concentration 10wt%,molar ratio of ethanol to oil 15:1,reaction temperature 70°C for 50 min,the FAEE yield of 84.6%was obtained.In addition,catalyst durability tests showed that the S-La₂O₃/NaY-800 catalyst could maintain higher than 75%FAEE yield after 5 cycles of operation.3.The composition and physicochemical properties of castor oil and prepared biodiesel were tested and analyzed.The main components of castor oil biodiesel included ethyl ricinoleate,ethyl oleate,ethyl palmitate,ethyl stearate and ethyl hexadecenoate,and the contents of ethyl ricinoleate was over 88.2%.The physicochemical properties of biodiesel were as follows:calorific value 38 MJ/kg,flash point 168 ^oC,cetane value 58,viscosity 11.2 mm²/s,density 915 g/cm³,acid value0.3077,condensation point-21 ^oC,cold filter point 4.9 ^oC,corrosiveness 1.The results showed that most of the physicochemical properties of castor oil biodiesel were comparable to that of ASTM,EN and GB biodiesel standard.