Catalytic conversion of palm oil into sustainable biodiesel using rice straw ash supported-calcium oxide as a heterogeneous catalyst: Process simulation and techno-economic analysis

This study aimed to optimize the process parameters and evaluated economic feasibility for biodiesel production. A pyrolytic rice straw ash (RSA) support with various amounts of calcium oxide (25–35 wt%) and calcination temperatures (600–800 °C) were used in the study. The results identified 35 wt% of CaO/RSA and calcination at 600 °C as the most effective catalyst with turnover frequency (TOF) of 2.88 h$^{−1}$ for biodiesel synthesis, giving a biodiesel yield of 96.49%. The optimal conditions for biodiesel production included a methanol: palm oil molar ratio of 9.34:1, a catalyst loading of 4.87 wt%, 175 min reaction time, and 65 °C reaction temperature. The study also included a techno-economic analysis of biodiesel production, revealing a payback period of 7.17 years, an internal rate of return of 17.20%, and a net present value of 4,151,905.61 USD. These findings pave the way for more sustainable and economically feasible biodiesel production.