Synthesis and Characterisation of Biodiesel from Cameroon Palm Kernel Seed Oil

Aims: This study was aimed at synthesizing and characterizing a biodiesel from Cameroon palm kernel oilseed.

Study Design: Synthesis was carried out on purified kernel oil by trans-esterification using methanol in basic medium.

Place and Duration of Study: Laboratory work was effectively carried out in the Department of Chemical Engineering (Ahmadu Bello University, Nigeria) in the early part of the year 2017.

Methodology: Oil was extracted from Cameroon palm kernel seed, which constitutes an agricultural industrial waste, by mechanical expression, was purified and analysed. Palm kernel oil (PKO) biodiesel was synthesised by trans-esterification in methanol with potassium hydroxide (KOH) as a base at the mass ratio PKO to methanol to KOH of 100:20:1.

Results: The yield of optimised synthesis of biodiesel was 97%, with a useful by-product (glycerol) which has potential pharmaceutical, cosmetic and engineering applications. PKO biodiesel was analysed using UV and IR spectroscopy and gas chromatography-mass spectrometry (GC-MS). Biodiesel had the following physical characteristics: specific gravity 0.884 g/mL, ASTM colour 1.5, viscosity at 40ºC 4.9080 cSt, viscosity at 100ºC 1.7914 cSt, cloud point 17ºC, pour point 0ºC, flash point 50ºC, aniline point 90ºF, cetane number 28, and diesel index 25. The following chemical parameters were obtained for the synthesized PKO Biodiesel: sulphur content 0.0328% w/v, acid value 0.4488 mg KOH/g, free fatty acid (FFA) content 0.2244 mg KOH/g, iodine value 7.36 mg I2/g, saponification value 168.30 mg KOH/g, ester value 154.84 mg KOH/g, hydroxyl value 51.89 mg OH/g and peroxide value 3.20 meq/kg.

Conclusion: These results of physical and chemical characterisation of PKO biodiesel fell in the range reported in the literature for biodiesel and were close to those of diesel fuel.