As demand for cellulose-based textile fibres continues to rise, researchers are exploring sustainable alternatives to traditional wood-derived pulp. A recent study published in RSC Sustainability demonstrates the potential of agricultural residues—specifically oat husks and wheat straw—as feedstocks for producing high-purity dissolving pulp, a precursor for fibres such as viscose and lyocell.

Addressing the “Cellulose Gap”

The global textile industry is facing a so-called “cellulose gap”, caused by limited cotton production and over-reliance on wood pulp. While wood remains the dominant source for dissolving pulp, it competes with other industries (such as construction and paper) and raises concerns about biodiversity loss and deforestation. Agricultural side streams offer a circular and non-food-competing alternative, with significant environmental advantages.

Agricultural Waste as Feedstock

The research evaluated several residues common in Sweden—wheat straw, oat husks, sugar beet pulp, and potato pulp—for their cellulose content, fibre structure, and ease of processing. While sugar beet and potato pulp were excluded due to poor processability, wheat straw and oat husks proved promising, containing high cellulose concentrations and favourable fibre morphology.

Soda Pulping and Bleaching Process

Using a soda pulping process, followed by acid pre-treatment and peroxide bleaching, the researchers succeeded in producing dissolving pulp with high cellulose purity (over 96%) and low hemicellulose and ash content. Importantly, these pulps showed properties comparable to commercial wood-based pulps, making them suitable for fibre production in sustainable textile applications.

Environmental and Process Viability

The study included life cycle assessments (LCA) and industrial-scale process simulations. While wheat straw required more energy and chemicals to process, it yielded more pulp and had a lower overall environmental impact than oat husks. Nevertheless, both materials outperformed conventional feedstocks in terms of resource circularity and waste reduction.

Implications for Designers and Manufacturers

For textile designers, fashion brands, and product developers focused on circular material innovation, these findings open up viable new pathways for sourcing regenerated cellulosic fibres from agricultural waste. By utilising existing side streams like oat husks and wheat straw, the industry can reduce pressure on forests, lower water consumption, and cut carbon emissions—all while supporting the transition to a circular bioeconomy.

Source: RSC Sustainability
Photo: olga Volkovitskaia