Solid-state characteristics of microcrystalline cellulose from oil palm empty fruit bunch fibre.

Abstract

Oil palm empty fruit bunches (EFB) are one of the by-products generated from palm oil mills. They consist mainly of lignocellulosic compounds, namely cellulose, hemicellulose and lignin. Cellulose, in particular, constitutes about 37% (dry weight) of the EFB, and is a compound with high value and can be exploited for the benefit of the palm oil industry. In this study, an attempt to prepare microcrystalline cellulose (MCC) from the isolated EFB-cellulose was carried out. The MCC was prepared by controlled acid hydrolysis of the isolated a-cellulose which attacked the amorphous region, and was followed by the back neutralization process with alkali. The structural properties of the cellulose and MCC were studied by Fourier Transformed Infra-red Spectrometry (FTIR) and X-ray diffraction methods. The FTIR spectrum of MCC from EFB was identical to that of the commercial MCC as well as the cellulose which showed comparable presence of C-O-C, C-C, O-H, and C-H bands. However, a broad peak at 3329 cm -1 was observed from the EFB-cellulose due to absorption vibration of the hydroxyl groups. The X-ray diffraction pattern revealed a low degree of order for EFB-cellulose and a relatively ordered structure for EFB-MCC. Two peaks of diffraction angles ranging between 19o and 23o were observed in the EFB-MCC, indicating the presence of a small percentage of cellulose II. The commercial MCC had a highly ordered structure compared to EFB-MCC as indicated by the presence of a single peak at 22.5o.