Optimization of Podocarpus falcatus Seed Oil Epoxidation Using a Sulfonated Carbon Catalyst Derived From Rice Husk

With the growing environmental concern and the limited global reserves of fossil fuels, the search for sustainable, nontoxic, and environmentally friendly substitutes for oil of mineral origin has become imperative. Podocarpus falcatus seed oil as a renewable resource for the production of epoxy oils has been explored in this research. The epoxidation reaction was catalyzed by a sulfonated carbon catalyst via carbonization of rice husk at various temperatures (400°C, 500°C, and 600°C). The catalyst that had been obtained at 600°C, which was selected based on its good characterization, was used for the optimization of the epoxidation reaction. Key process variables, namely, reaction temperature (650°C–850°C), time (2–6 h), catalyst loading (2–6 wt.%), and hydrogen peroxide‐to‐oil molar ratio (1.5:1–3.5:1), were investigated. Optimization of the reaction was performed with the help of Design Expert software, based on response surface methodology (RSM) through Box–Behnken design (BBD). Maximum oxirane oxygen content (3.905%) was achieved under optimum conditions: 84.68°C, 3.74 h, 5.8 wt.% catalyst loading, and a 2:1 M ratio of hydrogen peroxide to oil. The double bond conversion was 94.05%. In addition, an optimized 4‐4‐2 ANN model was developed based on a three‐layer backpropagation network. The properties of the Podocarpus falcatus oil and the resulting epoxidized oil were characterized by FT‐IR, NMR, and GC–MS. The results prove Podocarpus falcatus seed oil to be a suitable bio‐based feedstock for epoxy oil manufacture with potential to offer a sustainable and environmentally friendly alternative over petrochemical‐derived products.