Study the Stable Diatomite-supported Catalyst for Biodiesel Production

Abstract

The stable of natural diatomite supported by potassium hydroxide (KOH) as catalysts were synthesized for biodiesel production. A heterogeneous base catalyst prepared by impregnating KOH onto diatomite was also used to synthesize biodiesel from palm oil. All samples have been thoroughly characterized by Wavelength Dispersive X-ray Fluorescence (WDXRF), X-ray diffraction (XRD), N2 adsorption/desorption, Scanning electron microscopy (SEM), Energy dispersive spectrometer (EDS), and Temperature-programmed desorption of carbon dioxide (CO2-TPD). The XRD, XRF, and SEM results confi rm that adding KOH to diatomite results in structural change. The SiO2 and K2O phases form in the diatomite structural matrix during impregnation and the total basicity amount of this compound promotes the transesterifi cation process. A maximum fatty acid methyl ester (FAME) content of 84.56% was obtained. The reaction conditions were as follows: molar ratio of oil to methanol 1:9, catalyst loading 5 wt%, reaction time 2 h, and reaction temperature 75 °C. This work provides a possible new method for converting KOH from a homogeneous to a heterogeneous catalyst (Diatomite/KOH) that may show stable reusability, avoiding the separation and pollution problems in the environment.

Preparation of CaO@CeO2 Solid Base Catalysts Used for Biodiesel Production

“…While the pore diameters of all the samples were in the range of 8-10 nm, they were classified as mesoporous because the pore diameters ranged from 2 nm to 50 nm [19,20]. This is advantageous for large-reactant reactions because mesopore catalysts may decrease the transesterification reaction's pore diffusion limits in biodiesel production [21][22][23]. This is because larger pores promote reactant diffusion into pore channels, which increases their access to a large number of active sites [24].…”