<![CDATA[Abstract. This research illustrates the development of a bi-functional catalyst derived from a blend of agricultural waste materials, employing a hydrothermal method. The precursor materials included cocoa pods, eggshells, snail shells, and orange peels. The resulting bi-functional catalyst underwent characterization through a variety of techniques, such as FTIR, XRF, XRD, SEM, TGA-DTA, and both single-point and multi-point BET analyses. The FTIR and XRD analyses distinctly indicated the transformation of calcium carbonate (CaCO3) from the agro-waste precursors into calcium oxide (CaO). XRD further validated the crystalline structures and identified the oxide minerals present within the catalyst using an X-ray diffractometer. The DTA-DSC curve displayed notable endothermic peaks at 400 °C, indicating a decomposition reaction that leads to the formation of a new compound. The surface area of the bi-functional catalyst was assessed using single-point and multi-point Brunauer-Emmett-Teller (BET) methods, yielding values of 87.94 m²/g and 159.4 m²/g, respectively. Additionally, the adsorption surface area of the catalyst's pore size was measured at 165 m²/g, while the Langmuir surface area was found to be 2792 m²/g, as determined by the Barrett-Joyner-Halenda (BJH) method. The mean pore volume was calculated to be 812.5 cc/g, and the average pore diameter was 2.138 nm, as established through BJH analysis. The diverse surface property results underscore the substantial influence of surface area on the catalyst's activity, as a larger surface area facilitates more efficient interactions between reactants and active sites. Consequently, the agricultural waste materials represent a promising source of calcium oxide for various applications across numerous scientific and engineering disciplines. Keywords: Bi-functional, Cocoa pods, Eggshells, Snail shells, Orange peels ]]>
