FROM CITRUS AURANTIUM PRUNING WASTE TO HIGH VALUE BIOMATERIAL: ISOLATION AND CHARACTERIZATION OF CELLULOSE FIBERS

Abstract

Valorizing agricultural pruning residue is a sustainable way to produce in-demand, bio-based materials and reduce environmental issues related to the disposal and incineration of agricultural waste. In this context, our work focuses on the valorization of Citrus aurantium pruning waste through cellulose isolation. First, the chemical composition of the biomass was evaluated according to TAPPI standards, revealing a high content of holocellulose and α-cellulose (60.7 ± 3.06, 37.2 ± 1.76, respectively), promoting its suitability as a cellulose feedstock. The isolation process consisted of alkaline delignification, followed by sodium chlorite and acetate buffer bleaching treatment. The resulting material was characterized by evaluating its crystallinity, thermal stability and morphology. The XRD analysis revealed a crystallinity index of 68%, indicating a well preserved crystalline cellulose structure. The TGA demonstrated a major degradation peak at 350 °C and low residual mass consistent with the measured ash content. Morphological study revealed well individualized fibers with average length of 0.926 mm and width of 22 µm, and a moderate fine elements fraction. These results confirm that Citrus aurantium pruning waste is promising as alternative lignocellulosic feedstock for cellulose production, highlighting its potential for applications in biobased material fields.