Separation of Glycerides from Algal Lipid Extract Using Preparative Chromatography

Crude vegetable oils contain, in addition to glycerides, a range of co-extracted compounds whose composition depends strongly on the biological source. Their removal typically requires multi-stage refining, increasing process complexity as well as solvent and energy demands. In this study, a simple preparative chromatographic method was developed to purify crude algal lipid extracts and recover a glyceride-rich fraction. The process employed hexane as the mobile phase and cellulose-based materials as the stationary phase. The underlying separation mechanism was investigated experimentally using paper chromatography, thin-layer chromatography (TLC), and Fourier transform infrared spectroscopy (FTIR), and was further interpreted using Hansen solubility parameters (HSPs). Approximately 50% of the crude lipid extract was recovered as a glyceride-rich, colorless fraction. A secondary fraction enriched in sterols, chlorophylls, and carotenoids were also recovered, highlighting the potential for simultaneous purification and recovery of valuable lipid-associated compounds. To support potential process scale-up, regeneration of the stationary phase was evaluated, with each cycle required 0.225 L of fresh hexane and 0.1 L of fresh methanol. In addition, low-cost cellulose-rich residues, including used paperboard and wood dust, were successfully validated as alternative stationary phase materials. Overall, the proposed process provides a straightforward and potentially scalable approach to refining algal lipid extracts while enabling the recovery of additional value-added fractions and the use of inexpensive cellulose-based materials.