Influence of Fatty Acid Profiles during Supercritical Transesterification of Conventional and Non-Conventional Feedstocks: A Review

Abstract

In this study, the influence of fatty acids of both conventional and non-conventional oils in supercritical transesterification method has been reviewed. Literature on oils such as moringa oleifera, manketti, croton megalocarpus, palm and soybean has been reviewed to establish an understanding of the supercritical transesterification that employed methanol as alcohol. This study reveals that lower yield of methyl esters is observed when higher temperatures are employed in oils that are highly dominated with polyunsaturated fatty acids, such as manketti and croton megalocarpus. And the reason is that poly-unsaturated fatty acids that are present in the oils decompose easily at higher temperatures and thus reduce the methyl esters yield.

A study of production and characterization of Manketti (Ricinodendron rautonemii) methyl ester and its blends as a potential biodiesel feedstock

“…Based on the GC analysis, it was found that MME contained 18.3% saturated FAs and 81.7% unsaturated FAs compared to the values reported previously i.e. 17.2% saturated FAs and 82.9% unsaturated FAs by Kafuku and Mbarawa (2013) and 27.4% saturated FAs and 72.8% unsaturated FAs by Ruttoa and Enweremadu (2011). It can be concluded that MME, PEME and CIME are mainly dominated by unsaturated FAs while COME is dominated by saturated FAs.…”

“…Physico-chemical properties of MME Table 5 shows the physico-chemical properties of the produced MME in comparison with those of the CIME, COME and PEME (Ruttoa and Enweremadu, 2011;Atabani et al, 2013a;Kafuku and Mbarawa, 2013;Atabani et al, 2014). Having considered the data presented in Tables 3 and 4 for CMO and MME, it can be seen that the kinematic viscosity was successfully reduced from 132.75 to 8.03425 mm 2 /s, refractive index from 1.487 to 1.4698, and density at 40 °C from 925.1 to 887.8 kg/m 3 .…”

“…The young fruit is at first covered in fine small hairs on its thin but tough outer skin; under the skin is a narrow spongy layer, at first green, then turning whitish brown with maturity (Naturalhub, 2013). Fruits are egg-shaped, velvety and contain a thin layer of edible flesh around a thick, hard pitted nutshell that encloses the edible oil-bearing kernel (Kafuku and Mbarawa, 2013). The nuts yield a high quality yellow transparent edible oil of which about 60% is used for food and cosmetics.…”

“…Manketti (Ricinodendron rautonemii) oil is one of the possible alternative oil crops for biodiesel production. Most previous reports on this plant have been focused on its use in the herbal cosmetic industry (Kafuku and Mbarawa, 2013), and only recently Manketti was explored for biodiesel production (Ruttoa and Enweremadu, 2011;Kafuku and Mbarawa, 2013).…”

“…It can be defined as a mixture of mono-alkyl esters of long chain fatty acids (FA) derived from renewable lipids such as vegetable oils and animal fats when reacted with an alcohol (methanol or ethanol) in presence or absence of a catalyst (Demirbas, 2009;Atabani et al, 2012;Kafuku and Mbarawa, 2013). Biodiesel is biodegradable, non-toxic, renewable, and has low emissions of CO, SO2, particulates and hydrocarbons (HC) as compared to conventional diesel (Kafuku and Mbarawa, 2013). The use of vegetable oils (edible and nonedible) plays an important role in biodiesel production.…”