Efficacy of Fly Ash as Additive on the Physical Properties of Biodiesel Extracted from Neem Oil

Authors

  • Mubarak Musa Zakari
    Jigawa State Collage of Education
  • Auwalu Musa
  • Fa`iza Ahmad
  • Usman Idris Isma`il
  • Sani Garba Durumin Iya
  • Muhammad Uzair
  • Ibrahim Garba Shitu

Keywords:

Fly ash, FTIR, Neem oil, Pour point, Fire point

Abstract

Biodiesel is regarded as a sustainable alternative to conventional fossil fuels. This study investigated the influence of fly ash as a fuel additive on selected physical properties of biodiesel produced from neem (Azadirachta indica) oil through alkaline transesterification. The chemical composition of the fly ash was determined using X-ray fluorescence (XRF), while Fourier Transform Infrared (FTIR) spectroscopy confirmed the formation of fatty acid methyl esters (FAME). Fly ash was incorporated into the biodiesel at concentrations of 0.1–0.5 wt%, and its effects on pour point, flash point, fire point, and density were evaluated. XRF analysis showed that the fly ash consisted mainly of SiO₂ (52.63%), Al₂O₃ (24.41%), and CaO (10.04%), indicating the presence of mineral oxides capable of modifying fuel properties. FTIR spectra verified the successful conversion of neem oil into biodiesel through characteristic ester functional groups. The pour point decreased from 12°C for crude neem oil to 3°C at 0.3 wt% fly ash, indicating improved low-temperature flow behaviour. Flash point and fire point also decreased from 214°C and 222°C to 115°C and 133°C, respectively, at the same concentration. The density declined from 920 kg m⁻³ for crude neem oil to 870 kg m⁻³ at 15°C for biodiesel containing 0.5 wt% fly ash. Overall, fly ash effectively modified the physical properties of neem biodiesel, with 0.3 wt% providing the best balance between improved cold flow performance and acceptable fuel safety, demonstrating its potential as an economical and environmentally friendly biodiesel additive.

Dimensions

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Published

2026-08-07

How to Cite

Efficacy of Fly Ash as Additive on the Physical Properties of Biodiesel Extracted from Neem Oil (M. M. Zakari, A. Musa, F. Ahmad, U. I. Isma`il, S. G. D. Iya, M. Uzair, & I. G. Shitu, Trans.). (2026). Nigerian Journal of Applied Physics, 2(2), 213-221. https://doi.org/10.62292/njap-v2i2-2026-90

Issue

Vol. 2 No. 2 (2026): Nigerian Journal of Applied Physics - Vol. 2 No. 2

Section

Articles
Copyright & Licensing

Copyright (c) 2026 Mubarak Musa Zakari, Auwalu Musa, Fa`iza Ahmad, Usman Idris Isma`il, Sani Garba Durumin Iya, Muhammad Uzair, Ibrahim Garba Shitu

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

How to Cite

Efficacy of Fly Ash as Additive on the Physical Properties of Biodiesel Extracted from Neem Oil (M. M. Zakari, A. Musa, F. Ahmad, U. I. Isma`il, S. G. D. Iya, M. Uzair, & I. G. Shitu, Trans.). (2026). Nigerian Journal of Applied Physics, 2(2), 213-221. https://doi.org/10.62292/njap-v2i2-2026-90