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

Abstract

The depletion of fossil fuel reserves with increased fuel demand and global emissions has increased the search for ecofriendly renewable fuels with a low environmental impact. Biodiesel can be considered as mono-alkyl esters of long-chain fatty acids obtained from the transesterification of vegetable oils and animal fats. Economically low-cost biodiesel production has received considerable interest for blending with fossil-based diesel for a more sustainable future. Therefore, the current study focuses on synthesizing an efficient, low-cost heterogeneous CaO catalyst from waste egg and seashell using a solidstate method and applying it to the transesterification of Jatropha oil. The Ca 2 Fe 2 O 5 solid catalyst was prepared by doping calcined CaO with iron in a 2:1 ratio using ferric oxide (Fe 2 O 3 ). Furthermore, the catalyst was extruded and analytically characterized using XRD, FT IR, BET, and its basic strength was quantified by Hammett indicators. Later on, transesterification of Jatropha oil was optimized by varying reaction parameters, such as the molar ratio of methanol to Jatropha oil, reaction time, and catalyst loading. The maximum conversion yield was 96.3% at a 20:1 methanol-to-oil ratio and 80 bar N 2 pressure using 5% (w/w) catalyst loading. Furthermore, the catalytic recycling study demonstrated that the Ca 2 Fe 2 O 5 catalyst could retain > 70-80% of transesterification efficiency and stability up to 4 cycles under high acid value and moisture conditions.

Nanotechnology-based biodiesel: A comprehensive review on production, and utilization in diesel engine as a substitute of diesel fuel

“…This is achieved by reducing the activation energy while improving the response rate to attain equilibrium. Conventional catalysts, whether they are homogeneous or heterogeneous, as well as biocatalysts, are utilized in the manufacturing process of biodiesel for industrial purposes (Babatunde et al, 2022;Semwal et al, 2023). It is important to note that these catalysts have significant negative effects on the environment, the economy, and technology (Huang et al, 2018).…”