Lignocellulosic pruning waste adsorbents to remove emerging contaminants from tyre wear and pharmaceuticals present in wastewater in circular economy scenario

The following work explores a sustainable approach to repurpose organic waste from poplar pruning into lignocellulosic waste-based activated carbons (LPWACs) through environmentally friendly thermochemical processes and in line with circular economy principles. The developed LPWACs, activated by potassium hydroxide (KOH) at two different temperatures and weight ratios, exhibited promising textural properties with BET surface area (SBET) and total pore volume (VTOT) reaching up to 1336 m2·g-1 and 0.588 cm3·g-1, respectively. In addition, they displayed a developed microporous structure with a significant oxygen content (up to 11 %). These activated carbons were used to remove five emerging organic pollutants from the leaching of tyre wear particles (TWPs) and pharmaceuticals present in water. The increase in oxygen groups had a negative effect on the adsorption capacity of 1H-benzotriazole (BZTL), while electrostatic influences hindered diatrizoic acid (DZT) adsorption. LPWACs effectively remove pharmaceutical and tyre contaminants, supporting the circular economy in water treatment.

This work was financially supported by the Ministry of Science, Innovation and Universities of Spain (Proyectos de I + D + I «retos investigación», CICLIC, RTI2018-097158-B-C33) and Universitat Politècnica de Catalunya project ALECTORS-2023 (R-02393). The authors gratefully acknowledge financial support from the Principado of Asturias (FICYT, grants for research groups, AYUD/2021/51379) and the Ministry of Science and Innovation of Spain (“Proyectos Transición Ecológica y Transición Digital, 2021”, TED2021-131713B-I00).

Peer reviewed