Researchers at Graz University of Technology are investigating the use of discarded cotton clothing to produce stronger recycled paper, potentially transforming waste into valuable resources.
A recent initiative at Graz University of Technology (TU Graz) is exploring the potential of discarded cotton clothing as a significant resource for producing recycled paper, particularly for packaging materials. This innovative approach could enhance the tensile strength of paper products, which is vital for their functionality and durability.
The research is being conducted at the Institute for Biobased Products and Paper Technology, where the focus has shifted back to the use of old cotton textiles—a material historically utilized in papermaking before wood became the primary source. The process of converting wood into paper, which originated in the mid-19th century, supplanted the earlier reliance on rags, primarily linen, for creating durable paper products. Today, however, the growing problem of textile waste, particularly in Austria, is prompting scientists to seek new uses for discarded clothing.
Each year, Austria generates approximately 220,000 tons of textile waste, with around 30 to 40 percent consisting of cotton. Reporting to APA, Graz process engineer Thomas Harter noted that much of this material is currently incinerated, resulting in the loss of valuable resources. “That should be the last resort,” he stated, emphasizing the necessity to find alternative methods for utilizing these materials. Harter and his team are working to reintegrate textile waste into paper production processes.
Initial experimental results have been promising. The researchers have made significant strides in optimizing the method of extracting cellulose fibers from old clothing, enabling the production of cartons and other packaging materials. During their studies, they focused on identifying the right mill for processing the water-textile mix, determining optimal grinding times, and the ideal ratio of water to textiles. “At the end of our experiments, we obtained a suspension that is very similar to a normal paper suspension and that we can process into paper using established methods,” Harter explained.
The findings indicate that the incorporation of textile fibers can significantly enhance the tensile strength of recycled paper. Alexander Weissensteiner, a member of Harter’s team, reported that “even with a textile-based content of 30 percent, the paper is significantly stronger while the processability remains the same.” The superior strength is attributed to the longer length of the textile fibers, which average 1.7 millimeters, as compared to typical fibers found in conventional recycled paper.
As the team moves forward, they plan to scale the production process to an industrial level, which is essential for wider application and acceptance of the new material. The current recycling rate for packaging papers and cartons has already surpassed 80 percent, signaling a robust infrastructure into which these added textile fibers can be integrated. “By introducing textile fibers into this cycle, they remain usable for a long time,” Harter noted.
In addition to advancing the recycling of textile waste, the team is investigating ways to reduce energy consumption in the fiber extraction and grinding process. This includes testing various additives and enzymatic pre-treatments designed to facilitate better breakdown of the fibers. These developments mark a significant step toward not only repurposing textile waste but also enhancing the sustainability of paper production.
Source: Noah Wire Services
