Biodiesel synthesis and characterization using welted thistle plant (Carduus acanthoides) as source of new non-edible seed oil

ABSTRACT

In this work we applied base catalyzed transesterification to convert non-edible welted thistle oil (Carduus acanthoides) as new non-edible feedstock into biodiesel (Fatty acid methyl esters). The highest biodiesel yield of 88% was obtained using optimized reaction conditions of 70°C and 5:1 molar ratio (methanol:oil). The synthesized esters were characterize and confirmed by the application of NMR and FT-IR techniques. Gas chromatography and mass spectroscopy identified different fatty acids as palmatic acid (C16:0), oleic acid (C18:1), linoleic acid (18:2), arachidic acid (C20:0), eicosanic acid (C20:1), and erucic acid (C22:1) in the oil of welted thistle. Six corresponding methyl esters reported in welted thistle oil biodiesel includes 9-hexadecenoic acid, hexadecanoic acid, 9-octadecadienoic acid, 11-eicosanoic acid, eicosanoic acid and 13-docosenoicacid. Fuel properties, such as density @40°C Kg/L (0.8470), kinematic viscosity @ 40°C c St (4.37), flash point (95°C), cloud point (+4°C), pour point (−5°C), and sulfur contents (0.0112% wt) of the biodiesel produced were compatible with American Society for Testing and Materials D 6751 specifications.

KEYWORDS:

• FAMEs
• FT-IR
• GC-MS
• NMR
• non-edible oil
• welted thistle

Additional information

Funding

The authors are grateful for the financial assistance of this project to the Institute of Post Graduate studies (IPS), Universiti Sains Malaysia (USM), and TWAS fellowships program for developing world.