Sustainable Biofuel Production from Agricultural By-Products: Citrus Peels and Pumpkin Seeds as Feedstocks for Bioethanol and Biodiesel

Riham Bakr; Maryam Sameh Fathi; Maria Adel; Bola Fouad; Rahma Sayed

doi:10.29133/yyutbd.1559061

Sustainable Biofuel Production from Agricultural By-Products: Citrus Peels and Pumpkin Seeds as Feedstocks for Bioethanol and Biodiesel

Abstract

Energy is fundamental to development, and in correlation with the rapid population growth, its demand is escalating. The issues associated with fossil fuels, their depletion, and negative environmental effects have led to the exploration of alternative energy sources. Biofuels such as biodiesel and bioethanol have emerged as promising, renewable, and environmentally friendly alternatives. This study explores the sustainable production of bioethanol from Citrus peels and biodiesel from Pumpkin seed oil, assessing their potential contributions to energy efficiency and societal benefits. Citrus peels, underwent acid hydrolysis (0.5% H₂SO₄, 2 h) to release fermentable sugars, followed by anaerobic fermentation using 10% (v/v) Saccharomyces cerevisiaea. The resulting bioethanol was confirmed through qualitative analysis via Jones reagent. GC-MS of the hydrodistilled Citrus peel revealed 90.53% limonene in Citrus oil Biodiesel was produced via transesterification of pumpkin seed oil with methanol and potassium hydroxide (KOH) catalyst. GC-MS identified 65.9% unsaturated fatty acids (linoleic and oleic acids dominant), with a 97.5% yield, 0.7% ash content, and calorific value of 39,586 kJ/kg, meeting ASTM/EN standards. The study highlights the potential of utilizing agricultural waste and by-products in biofuel production, contributing to a circular economy and reducing environmental impact. The study demonstrates the viability of Citrus peel waste and Pumpkin seed oil as feedstocks, reducing reliance on fossil fuels while valorizing agricultural by-products. Challenges in scaling production require further exploration to maximize societal and environmental benefits, particularly in resource-rich regions.

Keywords

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Details

Primary Language

English

Subjects

Medicinal and Aromatic Plants

Journal Section

Research Article

Authors

Riham Bakr ^*
0000-0002-1010-8483
Egypt

Maryam Sameh Fathi
0009-0006-7872-0683
Egypt

Maria Adel
0009-0001-9867-4358
Egypt

Bola Fouad
0009-0006-8820-9598
Egypt

Rahma Sayed
0009-0006-4755-5814
Egypt

Early Pub Date

September 30, 2025

Publication Date

September 30, 2025

Submission Date

October 1, 2024

Acceptance Date

May 27, 2025

Published in Issue

Year 2025 Volume: 35 Number: 3

DOI

https://doi.org/10.29133/yyutbd.1559061

IZ

https://izlik.org/JA39GA67PX

Cite

RIS / Bibtex

APA

Bakr, R., Sameh Fathi, M., Adel, M., Fouad, B., & Sayed, R. (2025). Sustainable Biofuel Production from Agricultural By-Products: Citrus Peels and Pumpkin Seeds as Feedstocks for Bioethanol and Biodiesel. Yuzuncu Yıl University Journal of Agricultural Sciences, 35(3), 533-544. https://doi.org/10.29133/yyutbd.1559061

AMA

1.Bakr R, Sameh Fathi M, Adel M, Fouad B, Sayed R. Sustainable Biofuel Production from Agricultural By-Products: Citrus Peels and Pumpkin Seeds as Feedstocks for Bioethanol and Biodiesel. YYU J AGR SCI. 2025;35(3):533-544. doi:10.29133/yyutbd.1559061

Chicago

Bakr, Riham, Maryam Sameh Fathi, Maria Adel, Bola Fouad, and Rahma Sayed. 2025. “Sustainable Biofuel Production from Agricultural By-Products: Citrus Peels and Pumpkin Seeds As Feedstocks for Bioethanol and Biodiesel”. Yuzuncu Yıl University Journal of Agricultural Sciences 35 (3): 533-44. https://doi.org/10.29133/yyutbd.1559061.

EndNote

Bakr R, Sameh Fathi M, Adel M, Fouad B, Sayed R (September 1, 2025) Sustainable Biofuel Production from Agricultural By-Products: Citrus Peels and Pumpkin Seeds as Feedstocks for Bioethanol and Biodiesel. Yuzuncu Yıl University Journal of Agricultural Sciences 35 3 533–544.

IEEE

[1]R. Bakr, M. Sameh Fathi, M. Adel, B. Fouad, and R. Sayed, “Sustainable Biofuel Production from Agricultural By-Products: Citrus Peels and Pumpkin Seeds as Feedstocks for Bioethanol and Biodiesel”, YYU J AGR SCI, vol. 35, no. 3, pp. 533–544, Sept. 2025, doi: 10.29133/yyutbd.1559061.

ISNAD

Bakr, Riham - Sameh Fathi, Maryam - Adel, Maria - Fouad, Bola - Sayed, Rahma. “Sustainable Biofuel Production from Agricultural By-Products: Citrus Peels and Pumpkin Seeds As Feedstocks for Bioethanol and Biodiesel”. Yuzuncu Yıl University Journal of Agricultural Sciences 35/3 (September 1, 2025): 533-544. https://doi.org/10.29133/yyutbd.1559061.

JAMA

1.Bakr R, Sameh Fathi M, Adel M, Fouad B, Sayed R. Sustainable Biofuel Production from Agricultural By-Products: Citrus Peels and Pumpkin Seeds as Feedstocks for Bioethanol and Biodiesel. YYU J AGR SCI. 2025;35:533–544.

MLA

Bakr, Riham, et al. “Sustainable Biofuel Production from Agricultural By-Products: Citrus Peels and Pumpkin Seeds As Feedstocks for Bioethanol and Biodiesel”. Yuzuncu Yıl University Journal of Agricultural Sciences, vol. 35, no. 3, Sept. 2025, pp. 533-44, doi:10.29133/yyutbd.1559061.

Vancouver

1.Riham Bakr, Maryam Sameh Fathi, Maria Adel, Bola Fouad, Rahma Sayed. Sustainable Biofuel Production from Agricultural By-Products: Citrus Peels and Pumpkin Seeds as Feedstocks for Bioethanol and Biodiesel. YYU J AGR SCI. 2025 Sep. 1;35(3):533-44. doi:10.29133/yyutbd.1559061