SYNTHESIS OF HIBISCUS OIL FOR THE PRODUCTION OF ETHYL ESTERS USING ZEOLITE Y AS CATALYST

ABSTRACT Hibiscus oil (Hibiscus rosa sinensis), is rich in fatty acid and also serve as a promising feedstock for bethyl esters production due to its abundance and relatively high oil content. Zeolite is a widely used acid catalyst which offers several advantages such as high thermal stability and large surface area which makes it an excellent choice for transesterification reactions. The main objective of this study is to synthesize hibiscus oil for the production of ethyl esters for biodiesel using zeolite Y as a catalyst. Biodiesel has been mentioned as one of the alternative energy sources that can significantly solve most environmental and sustainability problems. This research work focused on the production of ethyl esters through transesterification and characterization of oil from hibiscus seed. This research work also discussed the experimental results obtained from the ethanolysis of hibiscus oil using zeolite Y as a heterogeneous catalyst, which the findings are organized into four main sections such as the FT-IR spectrum of ethyl esters from hibiscus oil which provides critical evidence of chemical transformation and a prominent absorption bands that typically appear around 1,740cm-1 for C=O stretching vibrations of esters, 2,850-2,950cm-1 for aliphatic C-H stretching and 1,160cm-1,230cm-1 for C-O stretching vibrations. It also showed the effect of molar ratio on yield of ethyl esters which demonstrate how ethyl esters yield increases with ethanol to oil molar ratio reaching an optimum of 12.1(91%) beyond which yield declined slightly due to excess ethanol, Also effect of catalyst loading on yield of ethyl esters which shows yield improved with catalyst loading up to 6wt%(90%) and then decline at higher concentration due to diffusion limitations, and effect of reaction time on yield of ethyl esters which indicate that biodiesel yield increased steadily with reaction time reaching an optimum of 91% at 3 hours after which no significant change has occurred. And lastly it shows the physical properties of hibiscus ethyl esters compared with the ASTM standard given that Density measured to be 0.87g/cm³ which falls perfectly within the range of 0.86-0.90 g/cm³, Viscosity was found to be 4.7 mm²/s which is within the range of 1.9-6.0mm²/s, Flash point measured to be 158⁰C which is slightly above the required minimum temperature of 130⁰C indicating that the synthesized fuel can be stored safely with a reduced risks of ignition, a cetane number of 51 which is good for ignition quality and heating value measured to be 39.2 MJ/Kg which falls within the expected range and is comparable to that of conventional diesel. In conclusion, this research successfully investigate the viability of using hibiscus oil as a feedstock for biodiesel production through a transesterification/ethanolysis process catalyzed by Zeolite Y. The study also systematically evaluate key reaction parameters to determinethe yield of fatty acid ethyl esters (FAEEs).