TITLE:
Valorization of Griffonia simplicifolia Seed Oil for Biodiesel Production: A Sustainable Alternative
AUTHORS:
Kosi Mawuéna Novidzro, Kwami Aldo Eric Kolor, Sassou Megnassan, Kossi Honoré Koumaglo
KEYWORDS:
Griffonia simplicifolia, Seed Cakes, Vegetable Oil, Biodiesel
JOURNAL NAME:
Engineering,
Vol.15 No.11,
November
28,
2023
ABSTRACT: Bio-derived oxygenated hydrocarbons, such as
mixtures of fatty acid methyl esters (biodiesel), are promising alternatives
for alleviating the adverse effects of fossil fuel consumption on climate
change and preventing petroleum resource depletion. However, the selection of a
viable feedstock for competitive biodiesel production remains challenging.
Recent studies focusing on Griffonia simplicifolia seeds, the sole plant industrially exploited for 5-hydroxy- tryptophan (5-HTP) extraction, have shown that G. simplicifolia seed oil (GSO) can be
solvent-extracted directly from ground seeds or the remaining seed cakes
obtained after 5-HTP extraction with quantitative yields. This work documents
the conversion of GSO into biodiesel through homogeneous base-catalyzed
transesterification. The refractive index and density of the obtained methyl
ester mixtures decreased with increasing oil-to-methanol molar ratio, reaction
temperature, and time. Under specific conditions, 1.43 wt% FFA oil, 63.5C, 60
min, and 1:9 oil/MeOH molar ratio with 1.2 wt% NaOH or 1.3 wt% KOH as
catalysts, optimal reaction conditions were reached. There were no significant
differences in the potential for diminution of the refractive index and density
between the NaOH and KOH catalysts. The predicted fuel properties based on the
fatty acid composition determined by GC-MS showed that G. simplicifolia biodiesel exhibited a cetane index of 50.29, volumetric energy density of 34.97
MJ/L, cloud point of -1.03°C, kinematic viscosity of 4.07 mm2/s,
and oxidative stability of 0.65 h. Apart from its unfavorable oxidative
stability and slightly lower energy density compared to petrodiesel, all other
calculated parameters met the current standards. The valorization concept
proposed in this study should be integrated into the 5-HTP extraction process,
preferably using the remaining dry seed cakes as raw materials to maximize revenue in a bioeconomic and sustainable
approach.