Synthesis And Characterization Of Heterogeneous Catalyst For Transesterification Of Vegetable Oil

Abstract

In this work, calcium oxide (CaO) extracted from eggshell impregnated with Zinc nitrate (Zn (NO3)2.6H2O) is prepared successfully and it had been applied on transesterification of sunflower oil. The effect of calcination temperature at (600⁰C 700⁰C, 800⁰C, 900⁰Cand1000⁰C for duration of time at 2h were studied. The catalytic performance of the prepared catalyst was examined by measuring basicity and confirmed by yield of Fatty acid methyl acid (FAME) through transesterification reaction. Response surface methodology (RSM) in combination with central composite design (CCD) was used to optimize the operating parameters. Methanol to oil molar ratio, catalyst loading and reaction temperature were chosen as the variables and the response selected was biodiesel yield. From the prepared catalyst the catalyst that was calcined at temperature of 600⁰C for duration of 2h and 20:80 mixture ratio of zinc nitrate to chicken eggshell was the best catalyst selected for synthesis of fatty acid methyl ester (FAME) and this catalyst was further characterized by X-ray Diffraction (XRD), Fourier transfer infrared spectroscopy (FTIR) and Hammett indicator method with in comparisons of raw mixture of zinc nitrate and chicken eggshell sample. The prepared catalyst is tested for transesterification of Sunflower oil to produce biodiesel in which the optimal conditions of a methanol; oil molar ratio of 9:1, the catalyst weight of 3%, the reaction temperature of 65 ◦C, and the reaction time of 2 h. the transesterification product which showed the biodiesel yield of over 82% was obtained at the recalcined temperature of 600 ◦C and reaction time of 2h. The reusability of zinc nitrate and chicken eggshell mixture calcined at 600⁰C for 2h catalyst has been reused successfully for five catalytic cycles. Heterogeneous base catalysts have advantages of being reusable, noncorrosive, show greater tolerance to water, improve biodiesel yield and purity, have a simpler purification process for glycerol and are easy to separate from the biodiesel product.