Agricultural residues are increasingly viewed as valuable renewable resources rather than waste, yet producing high-quality dissolving pulp from non-wood biomass remains technically challenging. Conventional pulping methods often rely on harsh chemicals that not only degrade cellulose but also generate significant environmental burdens.
A study recently accepted by the Journal of Bioresources and Bioproducts proposes a greener alternative using sugarcane bagasse as the raw material. The researchers developed an integrated process that combines carbonate-based oxygen-alkali pulping with enzymatic totally chlorine-free bleaching, aiming to maximize cellulose preservation while improving delignification efficiency.
The process begins with hydrothermal pretreatment, which selectively removed 83.7% of hemicellulose while retaining nearly 90% of the cellulose. During the subsequent pulping stage, partial replacement of sodium hydroxide with sodium carbonate regulated the balance of active oxygen species, promoting selective lignin oxidation instead of indiscriminate cellulose degradation. Response surface optimization identified the optimal pulping conditions at a 50% sodium carbonate substitution ratio, 105.8 °C, and a cooking time of three hours. Under these conditions, the process produced pulp with 36.5% yield, 47.6% ISO brightness, and 89.1% α-cellulose content.
The bleaching stage further enhanced pulp quality through the synergistic action of xylanase, laccase, and hydrogen peroxide. Rather than relying on chlorine-containing chemicals, the enzyme cascade selectively disrupted lignin-carbohydrate complexes and residual chromophoric structures, allowing the hydrogen peroxide dosage to remain low while achieving effective bleaching. The optimized sequence ultimately produced dissolving pulp with 81.2% ISO brightness, 91.02% α-cellulose content, 248 mL/g viscosity, and an overall yield of 30.8%, meeting industrial requirements for dissolving pulp.
Beyond reporting process performance, the study explains the mechanisms responsible for selective lignin removal. The authors demonstrate how sodium carbonate regulates reactive oxygen species during pulping, while enzyme pretreatment improves accessibility to residual lignin before peroxide bleaching. Compared with conventional sulfur-containing pulping and chlorine-based bleaching processes, the proposed route operates at a lower cooking temperature and reduces chemical consumption, providing both environmental and energy-saving advantages. The work offers a practical strategy for upgrading abundant sugarcane bagasse into high-value cellulose feedstock and highlights the potential of agricultural biomass in sustainable biorefinery applications.
See the article:
DOI
https://doi.org/10.1016/j.jobab.2026.100281
Original Source URL
https://www.sciencedirect.com/science/article/pii/S2369969826000538
Journal
Journal of Bioresources and Bioproducts
Experimental study
Not applicable
Green Production of Dissolving Pulp from Sugarcane Bagasse via Carbonate-Based Oxygen-Alkali Pulping and Enzymatic Totally Chlorine-Free Bleaching
30-Jun-2026