Mixed Aqueous Surfactants Solution for Rapid Oil Extraction from Palm Kernel Seed

Abstract

Adverse effects associated with the use of hexane or other similar organic extraction solvents for extracting oil from oilseeds have been a drive for alternative less toxic oil extracting solvents. This research focuses on oil extraction from grinded palm kernel using solution of mixed aqueous polyoxythylene (23) lauryl ether (BRIJ-35) and sodium dodecyl sulphate (SDS) surfactants and sodium chloride (NaCl) as the electrolyte. Grinded Biomass was agitated in the solution of the mixed surfactant, allowing the extracted oil to be liberated from the seeds as separate phase from the aqueous phase. The effect of SDS concentration, NaCl concentration, contact time and liquid/seed ratio on oil yield was studied. The extracted oil was subjected to Fourier Transform Infrared Spectroscope (FT-IR) characterization to determine the functional groups present in the oil. At optimum conditions for the mixed aqueous surfactant extraction (0.2379 wt.% SDS, 0.5995 wt.% BRIJ-35, 0.3wt.% NaCl, 10 ml/g liquid/solid ratio, 25 min contact time at 25oC), an optimum 78% oil yield was obtained. In contrast, at 50oC for 24hr, an optimum of 81% and 82% oil yield were obtained respectively when hexane and petroleum ether were used as oil extracting solvents. Addition of BRIJ-35 and NaCl to the SDS solution improved the oil yield. Oil extracted using mixed aqueous surfactants, petroleum ether and hexane have the same functional groups indicating the surfactant does not affect the quality of the oil extracted.