Work

Chemical recycling of post-consumer textile waste via continuous hydrothermal liquefaction and hydrotreatment for simultaneous monomer and hydrocarbons production

Year: 2025

Type: article

Abstract: • Continuous hydrothermal liquefaction was applied to recycle mixed textile waste. • The water recycling process significantly increases oil yield, from 6% to 39%. • Simultaneous recovery of terephthalic acid was achieved with a yield of 48 wt%. • Oil from mixed textile waste was hydrotreated into hydrocarbons for the first time. • Complete hydrogenation remains challenging due to resistant compounds in the oil. Textile waste streams pose a significant sustainability challenge for industry, particularly due to the complex, mixed composition and the presence of various chemical additives, such as colorants, dyes and other finishing chemical additives. This study utilizes hydrothermal liquefaction (HTL) with aqueous phase (AP) recirculation to chemically recycle real mixed textile waste, resulting in an increase from an initial 5 wt% to 27 wt% oil in batch reactors due to water saturation and the partitioning of less polar compounds from the aqueous phase into the oil phase. Continuous processing with AP recirculation further enhances the HTL oil yields to 39 wt% and enables the recovery of 48 wt% of terephthalic acid (TPA) from the original polyesters. The chemical recycling of TPA via HTL has a similar range of energy intensity as its direct synthesis from crude sources. The resulting oil was hydrotreated, producing a fully deoxygenated hydrocarbon mixture rich in a nitrogen free naphtha fraction. However, the full denitrogenation was not achieved in the kerosene, gas oil and bottom residue fractions. This study demonstrates the technical feasibility and energy efficiency of chemical recycling of mixed textile waste using HTL.

Source: Chemical Engineering Journal

DOI: 10.1016/j.cej.2025.161108

Authors: Aisha Matayeva, Juliano Souza dos Passos, Petr Straka, Sofie Klara Gissel Skibsted, Patrick Biller

Institutions: Aarhus University, University of Chemistry and Technology, Prague

Language: English

Topic: Thermochemical Biomass Conversion Processes

Subfield: Biomedical Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Responsible consumption and production

Open Access status: hybrid

Estimated APC paid: $4,830