Physio-chemical assessment of beauty leaf (Calophyllum inophyllum) as second-generation biodiesel feedstock

Recently, biodiesels from non-edible vegetable oil, known as second generation biodiesel, are receiving more attention because it can overcome food versus fuel crisis related to edible oils. The Beauty Leaf tree (Calophyllum Inophyllum) is a potential source of non-edible vegetable oil for producing future generation biodiesel because of its sustainability in a wide range of climate conditions, easy cultivation, high fruit production rate, and the high oil content in the seed. In this study, bio-oil was extracted from beauty leaf tree seeds through three different oil extraction methods. The important physical and chemical properties of produced beauty leaf oils were experimentally analysed and compared with commercial edible vegetable oils. Biodiesel was produced using a two-stage esterification process consisting of acid catalysed pre-esterification and alkali catalysed Transesterification. Fatty acid methyl ester (FAME) profile and physicochemical properties including kinematic viscosity, density, higher heating value and acid value were measured using laboratory standard testing equipment following internationally recognized testing procedures. Other fuel properties including oxidation stability, iodine value, cetane number, flash point, cold filter plugging point, cloud point and pour point temperature were estimated using Fatty acid methyl ester (FAME) of biodiesel. Physicochemical properties of beauty leaf oil biodiesels are described briefly and compared with recognised biodiesel standards and commercially available biodiesels produced from edible oil feedstock. Quality of produced biodiesel was assessed based 13 important chemical and physical properties through Preference Ranking Organisation Method for Enrichment Evaluation (PROMETHEE) and Graphical Analysis for Interactive Assistance (GAIA) analysis. This study found that Mechanical extraction using the screw press can produce oil from correctly prepared product at a low cost, however overall this method is ineffective with relatively low oil yields. The study found that seed preparation has a significant impact on oil yields, especially in the mechanical oil extraction method. High temperature and pressure in extraction process increases the performance of oil extraction. On the contrary, this process increases the free fatty acid content in the oil. Clear difference was found in physical properties of beauty leaf oils that eventually affected the oil to biodiesel conversion process. However, beauty leaf oils methyl esters (biodiesel) were very consistent and able to meet almost all indicators of biodiesel standards. Furthermore, it showed as a better automobile fuel compared to most of the commercially available biodiesels produced from edible oil sources. Result of this study indicated that, Beauty Leaf oil seed is readily available feedstock to commence the commercial production of 2nd generation biodiesel. The findings of this study are expected to serve as the basis from which industrial scale biodiesel production from Beauty Leaf can be made.