Eco-friendly approach for nanocellulose isolation from agricultural wastes and the fabrication of bioaerogel scaffolds

In this study, we employed supercritical carbon dioxide (scCO2) treatment under varying conditions: low-pressure treatment at 30 MPa and high temperature at 80 degrees C (LPHT group) and high-pressure treatment at 60 MPa and low temperature at 50 degrees C (HPLT group) for nanocellulose isolation. The scCO2 treatment resulted in smaller particle sizes and enhanced crystallinity. Notably, HPLT exhibited superior efficiency compared to LPHT treatment. Utilizing temperatures and pressures above the critical point effectively penetrated natural fibers, reducing nanocellulose particle sizes. Moreover, high-pressure and low -temperature nanocellulose demonstrated the highest crystallinity and negative zeta potential values (78.2% and -32.4 +/- 4.01 mV), surpassing those of the low-pressure and high -temperature group (77.9% and 26.0 +/- 2.34 mV) and control (77.3% and 25.9 +/- 3.13 mV). The concentration of nanocellulose significantly impacted the porosity, pore size, and water absorption of the bioaerogel scaffolds, indicating the potential for sustainable and environmentally friendly approaches in material fabrication for diverse applications.