Ultrasound-Assisted Extraction of Lignin from Oil Palm Frond

Ultrasound-assisted method is claimed as a simpler and more effective ways of extracting compared to conventional extraction methods for the extraction of bioactive compounds from natural products such as lignin. This study investigated the potential of ultrasound-assisted extraction to extract lignin from oil palm frond (OPF) as compared to conventional heating. The extraction had been carried out by using sodium hydroxide solution as a solvent. Factors such as extraction temperature and solvent concentration were also examined. The presences of lignin in the corresponding extracts were confirmed by FTIR analysis. The result obtained showed that the extraction of OPF assisted with ultrasound was more efficient in giving higher lignin yield compared to conventional heating. Other than that, the reaction temperature was lowered down and the reaction time was also shortened when the extraction was assisted by ultrasound. With all these merits, ultrasound-assisted extractions were more effective to be used and should be considered for a wider application in the extraction of lignin and other compounds from various plants.