Lignin isolation from black liquor from oil palm empty fruit bunch using acid
Sri Hidayati, Wisnu Satyajaya, Ahmad Fudholi
Abstract
This study aimed to obtain the characteristics of lignin isolated from oil palm empty fruit bunch by using HCl. Treatments were conducted using HCl at concentrations of 10%, 20%, 30% and 40% (v/v). Increasing HCl concentrations reduced yields but increased equivalent lignin weights and methoxyl contents. Results of functional group testing via Fourier transform infrared spectroscopy showed no change in the structure of functional groups at all HCl concentrations employed. Amongst the acid concentrations employed in this work, 20% HCl produced the maximum yield (15.61%). Increases in HCl concentration could increase methoxyl contents. In this study, average methoxyl contents were in in the range of 12.4–44.95%. The equivalent weight produced in this study ranged from 200% to 250%. Scanning electron microscopy–energy-dispersive X-ray results further showed that the dominant elements were carbon, oxygen, aluminium and iron. In addition, Chromatograms and identification of lignin compounds isolated using 40% HCl were presented.