Characteristics of formacell OPEFB lignin by potassium hydroxide precipitation

Formacell lignin derived from oil palm empty fruit bunches (OPEFBs) holds significant potential as a raw material for various industrial applications. However, its properties need enhancement for specific uses. This study investigated the influence of the potassium hydroxide concentration on the physicochemical properties of lignin extracted from the black liquor of OPEFBs. The chemical structure and functional groups were analyzed using pyrolysis-gas chromatography–mass spectrometry and Fourier transform infrared spectroscopy. Lignin was extracted via alkaline precipitation using potassium hydroxide (KOH) at concentrations of 5%–30%. The results indicate yields ranging from 3.57% to 14.95% on the basis of potassium hydroxide concentration. Increasing the potassium hydroxide concentration, increased lignin yields and decreased acid-insoluble lignin content. Thermogravimetric analysis demonstrated that lignin exhibited thermal stability, with degradation occurring between 100°C and 750°C. These findings suggest that lignin extraction via potassium hydroxide is an effective method for obtaining thermally stable lignin suitable for biopolymers and wood composites. However, further studies are needed to optimize the process, assess scalability, and evaluate environmental impacts. This research provides insight into improving lignin extraction techniques, enhancing its potential for sustainable industrial applications.