Utilizing Flax Straw for Sustainable Paper Production: Delignification Methods, Structural Analysis, and Fiber Size Distribution Effects

Abstract

This research explores the potential of agricultural waste, specifically flax straw, as a sustainable raw material for eco-friendly packaging materials. This study investigates a three-stage delignification process involving nitric acid, alkaline treatment, and organosolvent solutions. This method effectively removes lignin from the straw, resulting in high-quality technical pulp with 67.7% α-cellulose and a significantly reduced ash content (8.5%). X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were employed to characterize the treated flax straw. XRD analysis revealed changes in the cellulose structure, while TGA indicated enhanced thermal stability compared to untreated straw. Microscopic analysis of the pulp fibers shows a parallel and aligned arrangement, suggesting a high fiber content and a strong paper lattice. The particle size distribution of the ground pulp, influenced by fiber size, has implications for the packing density and mechanical properties of the final product. This study demonstrates the potential of agricultural waste as a sustainable source for packaging materials, contributing to the circular economy and waste reduction.