Comparison of CaO-NPs and Chicken Eggshell-Derived CaO in the Production of Biodiesel from Schinziophyton rautanenii (Mongongo) Nut Oil

Abstract

The ever-increasing population growth and economic developments have heightened demand for energy. This has resulted in depletion and ever-rising prices of petroleum diesel, thus increasing environmental degradation. These complications have motivated this study for the search of an alternative eco-friendly and renewable source of energy such as biodiesel. Biodiesel has been found to be a potential alternative fuel for diesel. Biodiesel was produced by transesterification reaction of Schinziophyton rautanenii (mongongo) nut oil in the presence of a base heterogeneous catalyst: CaO derived from eggshell ash and synthesised CaO-nanoparticles (CaO-NPs). The catalysts were calcined at a temperature of 800°C for 3 h and characterized by scanning electron microscope-energy dispersive X-ray (SEM-EDX) where both catalysts showed agglomerated particles and high elemental composition of Ca and O. Powder X-ray diffraction (XRD) showed that CaO was present in both catalysts, and the average crystalline size obtained was 42 and 50 nm for CaO-NPs and eggshell ash, respectively. Fourier transmission infrared (FTIR) spectrometer showed absorption bands of CaO in both catalysts which were at 875 and 713.46 cm−1 for CaO-NPs and eggshell ash, respectively. The analysis of mongongo nut oil (MNO) and mongongo methyl esters (MMEs) was done according to the European biodiesel specification (EN 1421) and American Society for Testing and Materials (ASTM D675). Statistically, there was no significant difference between CaO-NPs and eggshell in terms of optimum yield ( P > 0.05 ) using a sample t-test. However, in terms of catalyst loading, the eggshell was a better catalyst as it required a low catalyst load to obtain an optimum yield of 83% at 6 wt.% compared to CaO-NPs with an optimum yield of 85% at 12 wt.%. The reactions were all performed at constant reaction conditions of 9 : 1 methanol to oil ratio, 3 h reaction time, and 65°C reaction temperature.

Role of Extracted Nano-metal Oxides From Factory Wastes In Medical Applications

“…The two peaks appeared between 1173.43-1123.89cm -1 refers to C-O stretching vibration [26,30] The peaks at 638.45 cm -1 refers to C-H out of plane bending, and the strong band observed at 718.78 cm −1 is due to the(Ca-O) bond. These results agree with those of Mmusiet al [31] and Jalua et al [32]…”

Heterogeneous Calcium Oxide Catalytic Filaments for Three-Dimensional Printing: Preparation, Characterization, and Use in Methyl Ester Production

“…Heterogeneous base catalysts, including single alkaline earth metal oxides, mixed metal oxides, and supported alkali metal, have shown promising potential as effective catalysts for the transesterification reaction in biodiesel production . However, calcium oxide (CaO) is the most commonly utilized heterogeneous base catalyst for converting glycerides to ester, because of its lower cost, lower toxicity, and simpler synthesis of the calcite structure . Nahas et al studied biodiesel production from waste cooking oil using a CaO solid catalyst from waste scallop seashells.…”

“… 9 However, calcium oxide (CaO) is the most commonly utilized heterogeneous base catalyst for converting glycerides to ester, because of its lower cost, lower toxicity, and simpler synthesis of the calcite structure. 13 Nahas et al 10 studied biodiesel production from waste cooking oil using a CaO solid catalyst from waste scallop seashells. The results showed that 97% biodiesel was achieved under the conditions of 12:1 methanol to oil molar ratio, 10 wt % catalyst loading, and 4 h reaction time.…”