Comparative study of enhanced catalytic properties of clay-derived SiO₂ catalysts for biodiesel production from waste chicken fat

The use of biodiesel is a proactive measure that can be implemented to reduce emissions of greenhouse gases and other adverse environmental impacts. However, one of the major setbacks to biodiesel production is its relatively higher cost compared to petroleum diesel. The optimistic solution to this is valorization of biomasses like waste chicken fat (WCF) and clay for deriving non-edible oil and catalyst respectively. Herein, we report the synthesis of clay derived SiO₂ catalyst impregnated with SrO, Bi₂O₃, CuO and CaO. The developed catalysts were characterized by FTIR, XRD, and SEM. XRD studies confirmed the successful impregnation of active metallic oxide on SiO₂ support. Further, these catalysts were employed for biodiesel production from WCF, and SrO/SiO₂ was found to be most effective and efficient catalyst for biodiesel production from WCF. Hence, SrO/SiO₂ was adapted to optimize the different transesterification reaction parameters such as methanol to oil ratio, catalyst loading, reaction temperature and time. The optimized conditions for maximum biodiesel yield 98.9% were found to be 65 °C in 1 h with 12:1 methanol to oil ratio and 1 wt% catalyst loading. The biodiesel produced was also analyzed by GC-MS. The obtained biodiesel yield shows that clay can be a potential, and cost-effective, catalyst source to produce biodiesel from WCF.