Synthesis of Ca–Fe-based heterogeneous catalyst from waste shells and their application for transesterification of Jatropha oil

The depletion of fossil fuel reserves with increased demand and global emissions has the search for eco-friendly renewable fuels a low environmental impact. Biodiesel can be considered as mono-alkyl esters long-chain fatty acids obtained from transesterification vegetable oils animal fats. Economically low-cost biodiesel production received considerable interest blending fossil-based diesel more sustainable future. Therefore, current study focuses on synthesizing an efficient, heterogeneous CaO catalyst waste egg seashell using solid-state method applying it to Jatropha oil. Ca2Fe2O5 solid was prepared by doping calcined iron in 2:1 ratio ferric oxide (Fe2O3). Furthermore, extruded analytically characterized XRD, FT IR, BET, its basic strength quantified Hammett indicators. Later on, oil optimized varying reaction parameters, such molar methanol oil, time, loading. maximum conversion yield 96.3% at 20:1 methanol-to-oil 80 bar N2 pressure 5% (w/w) catalytic recycling demonstrated that could retain > 70–80% efficiency stability up 4 cycles under high acid value moisture conditions.