Four different alkaline treatments for isolation of cellulose microfibrils from vascular bundles of banana rachis were comparatively studied. Isolated cellulose microfibrils were characterized using high performance anion exchange chromatography for neutral sugar composition, as well as attenuated total reflection Fourier transform infrared spectroscopy, transmission electron microscopy, X-ray and electron diffraction and solid-state 13C NMR. The cellulose microfibrils treated with peroxide alkaline, peroxide alkaline-hydrochloric acid or 5 wt% potassium hydroxide had average diameters of 3-5 nm, estimated lengths of several micrometers. Although the interpretation of their structure is difficult because of the low cristallinity, X-ray diffraction, 13C NMR and ATR-FTIR results suggested that cellulose microfibrils from banana rachis could be either interpreted as cellulose IV1 or cellulose Iβ. The specimens treated with a more concentrated KOH solution (18 wt%) were still microfibrillated but their structure was converted to cellulose II. Crown
Bibliographical noteFunding Information:
The authors would like to thank Colciencias for the financial support that has made this research work possible, as well as Y. Nishiyama and H. Chanzy (CERMAV) for helpful suggestions. We also thank Dr. S. Curling (Napier University) by the analyzing of monosaccharides using high performance anion exchange chromatography.
- Agro-industrial residues
- Banana rachis
- Cellulose microfibrils
- Chemical treatments
- Crystalline structure