Experimental study on the high-temperature co-pyrolysis of Elm and waste textiles

Abstract

To address the dual challenges of rising energy demand and solid waste valorization, this study conducted high-temperature co-pyrolysis experiments of Elm with Waste Textiles (PET, Cotton) in a vertical furnace and thermogravimetric analyzer. The experiments revealed that co-pyrolysis significantly altered the product distribution and composition, manifested by an increase in gas yield and a decrease in liquid yield. Co-pyrolysis of Elm with both textiles consistently promoted the generation of H₂ and CO while simultaneously suppressing CH₄ production. Notably, co-pyrolysis with Cotton yielded significantly higher amounts of H₂ (31.02 mmol) and CO (43.59 mmol) than co-pyrolysis with PET. Regarding the liquid products, the addition of PET substantially increased the aromatic hydrocarbon content (reaching a maximum of 81.20 %) and significantly inhibited the formation of phenols. Although the addition of Cotton also increased the aromatic content, the extent of this increase was lower than that observed with PET. Thermogravimetric-mass spectrometric (TG-MS) analysis further elucidated that: The Elm-PET mixture exhibited an inhibitory effect during the low-temperature co-pyrolysis stage, characterized by delayed thermal weight loss peaks and increased residual mass, while promoting H₂ generation and inhibiting CH₄ release; Conversely, the Elm-Cotton mixture, due to overlapping pyrolysis temperature ranges, demonstrated a significant synergistic effect (evidenced by an increased DTG peak height), while also promoting CO release.