Abstract
Oil palm empty fruit bunch (OPEFB) with a cellulose content of 39 wt% is a good promise to be an alternative lignocellulosic feedstock for cellulose production through environmentally friendly extraction process. Therefore, this research was aimed to establish an effective cellulose extraction scheme from OPEFB via introduction of ultrasonication in the alkaline pulping stage for process intensification. The process could greatly reduce alkali solvent usage for cellulose extraction, hence alleviating the environmental impact caused by chemical disposal. Firstly, four distinct pre-treatment techniques had been used to pre-treat the OPEFB powder, namely autoclave, organosolv, acid and microwave pre-treatments. Afterwards, the pre-treated samples further underwent ultrasonic-assisted alkali extraction to extract the cellulose content. It was observed that the autoclave pre-treated ultrasonic extract achieved the highest cellulose content of 77.14 wt% at optimum KOH concentration of 0.75 M, ultrasonic amplitude of 30%, duration of 30 min and temperature of 80 °C. Therefore, the introduction of ultrasonication in alkali extraction of cellulose was indeed an effective approach in establishing a green production scheme of cellulose from lignocellulose.
Synthesis of cellulose nanocrystals (CNCS) from oil palm empty fruit bunch by hydrothermal with pre-treatment sonication
