Valorization of Rosa centifolia Wastes: Extraction and Physico-chemical Characterization of Cellulosic Microfibers

The production of floral water and essential oils by hydro-distillation of aromatic and medicinal plants leads to the formation of lignocellulosic wastes in large quantities, which has an immense impact on the ecosystem and the economy. The valorization of these inexpensive, affordable, and renewable residues will not only solve these issues, but also offer attractive and sustainable raw materials for green chemistry. The aim of this work was to explore, for the first time, the valorization of hydro-distillation wastes from Rosa centifolia as renewable bio-resources for the extraction of cellulosic microfibers. The cellulosic microfibers were extracted from these wastes using combined chemical treatments (dewaxing step, hot water treatment, alkaline treatment, and bleaching step). The chemical analysis of the raw material showed that it is composed of 32.38 ± 0.52% wt. α-cellulose, 26.49 ± 0.45% wt. hemicelluloses, and 22.39 ± 1.17% wt. lignin, among other components. The yield, α-cellulose content, and average diameter of the extracted cellulosic microfibers were 31.65 ± 0.584%, 78.21 ± 0.285%, and 12.52 ± 0.421 µm, respectively. The effectiveness of the performed treatments for the elimination of lignin and hemicelluloses from the surface of the studied fibers was verified by different techniques: colorimetry, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The results of the characterization of the isolated cellulose indicated a good whiteness index (75.65) and a moderate crystallinity (56%). The findings are promising to take advantage of these bio-resources for the extraction of cellulosic microfibers and their potential application in the fields of chemicals, bio-based materials, and energy recovery.