Upcycling industrial peach waste to produce dissolving pulp

This study investigates the production of high-purity cellulose pulp from peach (Prunus persica) fruit wastes generated during the processing of a Greek compote and juice production industry. A three-step chemical process is used, including alkaline treatment with NaOH, organic acid (acetic and formic) treatment, and hydrogen peroxide treatment, with the goal of cellulose extraction and purification. A fractional factorial design optimized reagent levels, revealing the strong influence of NaOH concentration on α-cellulose content and degree of polymerization. The extraction yield ranged between 9.7 and 12.3%, and a yield of 11.6% was achieved under the optimal conditions (NaOH, 3%w/v; acid-to-solid ratio, 6 l/kg; H₂O₂, 0.5% v/v) of the factorial experiment. The resulting samples were further characterized by XRD, FTIR, SEM, and TGA techniques. The results of the XRD and FTIR spectra confirmed the presence of cellulose, with a crystallinity index of approximately 57%, balancing strength and reactivity. The SEM analysis demonstrated a strong morphological similarity between the extracted pulp and commercial dissolving-grade pulp (Södra Purple), while images of the raw material confirmed effective purification. Additional evaluations included color, lightness, and lignin content. These findings suggest that cellulose extracted from peach waste is suitable for textile applications, offering a sustainable alternative to conventional cellulose sources and supporting industrial resource efficiency.

Graphical Abstract