Cellulose Nanocrystals from Postconsumer Cotton and Blended Fabrics: A Study on Their Properties, Chemical Composition, and Process Efficiency

Abstract

From manufacturing to disposal, the textile industry faces multiple challenges to achieve sustainability and reduce its environmental impact. This work investigates the properties and composition of cellulose nanocrystals (CNCs) extracted from clothing waste made of cotton fibers. We isolated CNCs from cotton, polyester/cotton, and acrylic/cotton waste fabrics through acid hydrolysis with sulfuric acid. A yield of 51−62 wt % (cotton basis) was obtained, and nearly all the polyester and acrylic fibers contained in the initial fabrics were recovered in a convenient shape that could allow easier recycling. CNCs extracted from the selected fabrics showed high purity, similar structural, physical, and chemical characteristics, and their properties were comparable to those extracted from virgin sources, although their surface chemistry and elemental composition slightly differed. The chemical components in the waste fabrics and the extracted CNCs were evaluated through a nontarget chromatographic-mass spectrometric screening strategy. Both the recycled textiles and the CNCs contained hundreds of compounds common in postconsumer textiles, including some with health and environmental concerns. However, our initial findings show that their concentrations in the CNCs are negligible. Our results provide insights into the challenges associated with the use of cotton waste textiles for the extraction of cellulose nanoparticles, and into the potential applications of the extracted nanomaterials.

Citrated cellulose nanocrystals from post-consumer cotton textiles

“…In this work we explore 1) the environmental impact of post-consumer cotton over wood pulp as raw material for CNC extraction and 2) the environmental impacts of lab-scale routes for CNC extraction. Three different CNC preparation scenarios were assessed: S1) CNC prepared from wood pulp by sulfuric acid hydrolysis 52,53 , S2) CNC prepared from post-consumer cotton by sulfuric acid hydrolysis 17 , and S3) CNC prepared from post-consumer cotton by citric acid functionalization and subsequent fibrillation (this work). For the post-consumer cotton, the cut-off allocation was applied meaning that recycled material can be used without burden (up to the recycling process) since the production (e.g., cultivation, harvesting, and processing) of the material is allocated to the first use of the material.…”

“…Packaging and material flow for the laboratory equipment was not considered at any point during this stage of the study. The main sources of data about the relevant preparation routes are from this and our previous works 17,53 . The other source of data is the Ecoinvent database (version 3.8), from which inventory data for upstream manufacturing data for pulp, chemicals, water, and electricity has been obtained using the inventory database provided within SimaPro Version 9.3.…”

“…Cellulose nanocrystals (CNCs) are rod-like nanomaterials with high crystallinity commonly extracted through acid hydrolysis 10 . In our previous work, we extracted CNCs from post-consumer cotton and blended fabrics through sulfuric acid hydrolysis 17 . Our results showed that while residual dyes remained attached to the nanocrystals, their properties were equivalent to CNCs extracted from virgin cotton 17 .…”

Chemical Recycling of a Textile Blend from Polyester and Viscose, Part I: Process Description, Characterization, and Utilization of the Recycled Cellulose

“…For regenerated fibers, the DP might be too low after separation, and, consequently, the cellulose fibers would not be suitable as raw material for conventional fiber-to-fiber recycling, but may be recovered as other products [17]. One option could be to produce cellulose nanocrystals from the cellulose fraction, which has been demonstrated using both cotton and cotton/PET blends as a raw material [18,19]. Furthermore, the complete depolymerization of cellulose into glucose allows for the production of specialty chemicals or biofuels [20].…”

A Critical Review on Modification Methods of Cement Composites with Nanocellulose and Reaction Conditions during Nanocellulose Production

“…Nanocellulose has gained a great deal of recognition among researchers thanks to its unique properties that combine the properties of cellulose and the unique characteristics of nanomaterials. In addition, it can be made from recycled materials such as cotton clothes or waste paper [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ], which fits perfectly with the idea of sustainable construction and waste management. Because it is a biomass material, it is biodegradable, renewable, and environmentally friendly.…”