Microfibrillated Cellulose Fabrication and Characterization from Sri Lankan Rice Straw: A Comparison between Traditional and Hybrid Variety

Rice is one of the major cereal crops cultivated globally. In the recent past, rice straw has gained momentum as a source of cellulose. However, it is notable that rice straw generated from rice cultivation has less or no commercial value. In this study, microfibrillated cellulose (MFC) was extracted from Sri Lankan traditional rice straw variety Pachaperumal and hybrid variety BG352 in two distinct stages. Initially, a series of chemical treatment methods that includes removal of wax and oil, lignin, hemicellulose and silica was employed to extract cellulose fibers from the aforementioned rice straw varieties. Then, using high-intensity ultrasonication (HIUS) process microfibrillated cellulose (MFC) was isolated from the obtained chemically extracted cellulose fibers. FTIR analysis validated that the chemical composition of MFC from both varieties were mainly cellulose where hemicelluloses and lignin were successfully removed during the set of chemical processes. Study revealed that around 34 per cent cellulose was extracted from Pachaperumal and around 25 per cent cellulose was extracted from BG352. Out of these chemically extracted cellulose fibers around 16 per cent of MFC was disintegrated from Pachaperumal and around 9 per cent from BG352 via HIUS process. SEM analysis showed that the diameters of the MFC were in 200 to 300 nanometer range Results indicated that traditional variety yielded high amount of MFC than technically modified variety via the efficient multi-step treatment process with potential industrial applications.