Volume: 4, 2025
4th International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland:
ENVIRONMENT – PLANT – ANIMAL – PRODUCT
Abstract number: E002
DOI: https://doi.org/10.24326/ICDSUPL4.E002
Published online: 9 April 2025
ICDSUPL, 4, E002 (2025)
Efficient removal of potentially toxic elements from digested sewage sludges using protic ionic liquids
Wiktoria Błaszczyk1*, Karolina Fila1, Monika Raczkiewicz2, Tadeusz Paszko1, Patryk Oleszczuk2, Anna Siatecka1
1 Department of Chemistry, Faculty of Food Science and Biotechnology, University of Life Sciences, Akademicka 15, 20-950 Lublin, Poland
2 Department of Radiochemistry and Environmental Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University, Marii Skłodowskiej-Curie 3, 20-031 Lublin, Poland
* Corresponding author: wiktoria.blaszczyk@up.lublin.pl
Abstract
The agricultural use of sewage sludges (SSLs) aligns with the principles of sustainable development and the circular economy, providing an effective waste management solution. However, SSLs, especially after advanced stabilization processes such as anaerobic digestion, often contain higher levels of potentially toxic elements (PTEs) than before stabilization, which may limit their environmental applications. The aim of this study was to apply protic ionic liquids (PILs) with diverse properties (1-methylimidazolium chloride ([H1Cim]Cl), triethylammonium hydrogen sulfate ([TEA][HSO4]), and 1-methylimidazolium hydrogen sulfate ([H1Cim][HSO4])) for the removal of PTEs from digested SSLs. The focus was on the extraction of Zn, Cu, Cd, Pb, Ni, and Cr, whose contents in SSLs used in agriculture are subject to legal regulations. In addition to determining the removal efficiency, the study investigated the mechanism of action of individual PILs. Under optimal conditions, [H1Cim]Cl exhibited the highest metal extraction efficiency, removing between 11% and 82% of PTEs depending on the metal type. The results indicated that extraction parameters (temperature, SSL:PIL ratio, number of ethanol washing cycles), as well as the type of SSL and the chemical forms of PTEs in SSL, significantly influenced process efficiency. The efficiency of [TEA][HSO4] was lower than that of the most effective [H1Cim]Cl and ranged from 5% to 70% for the same PTEs. [H1Cim][HSO4] was found to be impractical due to difficulties in separation from the treated SSL. The obtained results confirm the effectiveness of PTE removal from SSLs using selected PILs, which may represent an interesting approach to SSL management in line with circular economy principles.
This research was funded in whole by National Science Centre, Poland under Grant number 2021/43/D/NZ9/02718.
Keywords: protic ionic liquids, 1-methylimidazolium chloride, triethylammonium hydrogen sulfate, potentially toxic elements
How to cite
W. Błaszczyk, K. Fila, M. Raczkiewicz, T. Paszko, P. Oleszczuk, A. Siatecka, 2025. Efficient removal of potentially toxic elements from digested sewage sludges using protic ionic liquids. In: 4th International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland: Environment – Plant – Animal – Product. https://doi.org/10.24326/ICDSUPL4.E002