Synthesis of Biodiesel Using Heterogeneous Catalyst Sodium Hydroxide Impregnated on Naturally Available SiO2

With the suspected exhaustion of fossil fuels in a couple of years there is a necessity for an alternative renewable source of energy. Biodiesel proves to be a very good alternative to handle this energy crisis. Enormous research is being done in the field of biodiesel production by employing homogeneous and heterogeneous catalysts. The homogeneous catalyst such as NaOH are meritorious as they give high conversions, but it has its own drawbacks as, difficulty of separation and non-reusability. In order to provide an economical and sustainable solution, the present work highlights the synthesis of heterogeneous NaOH impregnated on naturally available SiO2. The naturally available diatomaceous earth samples (four samples) were collected and subjected to acid treatment and loss on ignition test to remove the impurities present within the sample. The treated samples were subjected to various characterization techniques such as XRD, FTIR, BET, and elemental analysis. The characterization results authenticate its usability as a catalyst support. It was observed that sample 004 had the highest silica content (90.95%) further, NaOH was impregnated on this sample. The synthesized catalyst was used for producing biodiesel from sunflower oil. The yield obtained was 94.32% and the properties of the biodiesel such as flash point, pour point, and cloud point, etc., were tested and the results were in good agreement with the literature. The FTIR analysis of the synthesized biodiesel and commercial diesel were done and the results showed a good match in composition.