Year: 2026
Type: article
Abstract: Cotton textile waste is challenging to digest and convert to biogas during anaerobic digestion (AD) due to high crystallinity of cellulose. This study investigated thermal hydrolysis pretreatment (THP) at 120–200 °C for 30 and 60 min to enhance cotton biodegradability prior 21 days of mesophilic AD at a substrate-to-inoculum ratio of 0.5 volatile solids (VS) basis. THP increased cotton solubilisation up to 98% VS removal, at the most sever condition (200 °C, 60 min), crystallinity decreased by 11.84% and COD solubilisation reached 51. However, the highest methane yield was achieved under moderate conditions (140 °C, 60 min), producing 17.92 mL CH 4 /g VS, representing a 123% increase over untreated cotton, indicating an optimal balance between solubilisation and process inhibition. Gompertz modelling showed excellent agreement ( R 2 ≥ 0.99), with a reduced lag phase (2.3 days) and ~2-fold higher biodegradability than untreated cotton. Digestate pH, ammonia nitrogen, and volatile fatty acid (VFA) remained within non-inhibitory ranges under the optimal THP condition, supporting stable and efficient methane production. These results identify cotton-specific THP operating conditions and demonstrate THP-AD as a pathway for valorising cotton textile waste.
Authors: N. Tharmarajah, K. Shahbaz, S. Baroutian
Institutions: University of Auckland, James Cook University
Language: English
Subfield: Building and Construction
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,490
Funder: University of Auckland
OpenAlex ID: W7154481490