Production and performance evaluation of biodiesel from Elaeis guineensis using natural snail shell-based heterogeneous catalyst: kinetics, modeling and optimisation by artificial neural network

Chinwe P Okonkwo; Vincent I E Ajiwe; Alexander I Ikeuba; Wilfred Emori; Modestus O Okwu; Jude I Ayogu

doi:10.1039/d3ra02456c

Production and performance evaluation of biodiesel from Elaeis guineensis using natural snail shell-based heterogeneous catalyst: kinetics, modeling and optimisation by artificial neural network

RSC Adv. 2023 Jun 28;13(28):19495-19507. doi: 10.1039/d3ra02456c. eCollection 2023 Jun 22.

Authors

Chinwe P Okonkwo¹, Vincent I E Ajiwe¹, Alexander I Ikeuba², Wilfred Emori³, Modestus O Okwu⁴, Jude I Ayogu^{5

6}

Affiliations

¹ Department of Pure and Industrial Chemistry, Nnamdi Azikiwe University Awka Nigeria cp.okonkwo@unizik.edu.ng.
² Materials Chemistry Research Group, Department of Pure and Applied Chemistry, University of Calabar Calabar Nigeria.
³ School of Materials Science and Engineering Sichuan University of Science and Engineering Sichuan Province PR China.
⁴ Department of Mechanical Engineering, Federal University of Petroleum Resources Effurun Ugbomoro Nigeria.
⁵ Department of Pure and Industrial Chemistry, University of Nigeria Nsukka 410001 Nigeria jude.ayogu@unn.edu.ng.
⁶ Department of Chemistry, Faculty of Mathematical and Physical Science, University College London London WC1E 6BT UK.

Abstract

This study presents an approach to produce biodiesel from Elaeis guineensis using natural heterogeneous catalysts derived from raw, calcined, and acid-activated forms of waste snail shells. The catalysts were thoroughly characterized using SEM, and process parameters were systematically evaluated during biodiesel production. Our results demonstrate a remarkable crop oil yield of 58.87%, with kinetic studies confirming second-order kinetics and activation energies of 43.70 kJ mol^-1 and 45.70 kJ mol^-1 for methylation and ethylation, respectively. SEM analysis identified the calcined catalyst as the most effective, exhibiting remarkable reusability for continuous reactions running up to five times. Moreover, the acid concentration from exhaust fumes yielded a low acid value (B100 0.0012 g dm^-3), significantly lower than that of petroleum diesel, while the fuel properties and blends satisfied the ASTM standards. The sample-heavy metals were well within acceptable limits, confirming the quality and safety of the final product. Our modelling and optimization approach produced a remarkably low mean squared error (MSE) and a high coefficient of determination (R), providing strong evidence for the viability of this approach at an industrial scale. Our results represent a significant input in sustainable biodiesel production and underscore the enormous potential of natural heterogeneous catalysts derived from waste snail shells for achieving sustainable and environmentally friendly biodiesel production.