Impregnation of granular activated carbon with nickel or copper improves performance of microbial electrosynthesis

Igor Vassilev; Hui Yao; Sadaf Shakeel; Markus Tuominen; Anne Heponiemi; Davide Bergna; Ulla Lassi; Marika Kokko

doi:10.1016/j.biortech.2024.131914

Impregnation of granular activated carbon with nickel or copper improves performance of microbial electrosynthesis

Bioresour Technol. 2024 Nov 29:418:131914. doi: 10.1016/j.biortech.2024.131914. Online ahead of print.

Authors

Igor Vassilev¹, Hui Yao¹, Sadaf Shakeel¹, Markus Tuominen¹, Anne Heponiemi², Davide Bergna³, Ulla Lassi³, Marika Kokko⁴

Affiliations

¹ Faculty of Engineering and Natural Sciences, Tampere University, P.O. Box 541, FI-33104, Finland.
² Research Unit of Sustainable Chemistry, P.O. Box 4300, FI-90014, University of Oulu, Finland.
³ Research Unit of Sustainable Chemistry, P.O. Box 4300, FI-90014, University of Oulu, Finland; University of Jyvaskyla, Kokkola University Consortium Chydenius, P.O. Box 567, 67701 Kokkola, Finland.
⁴ Faculty of Engineering and Natural Sciences, Tampere University, P.O. Box 541, FI-33104, Finland. Electronic address: marika.kokko@tuni.fi.

PMID: 39617349
DOI: 10.1016/j.biortech.2024.131914

Abstract

Microbial electrosynthesis (MES) utilizes renewable electricity to power microbial conversion of carbon dioxide into multi-carbon products. As the cathode electrodes serve both as source of reducing equivalents and provide surface area for biofilm growth, the electrode material plays a crucial role in MES. In this study, granular activated carbon (GAC) was impregnated with copper or nickel (5 wt%) and used as MES cathode. In abiotic runs, metal impregnated GAC resulted in higher current densities, on average up to 5.6 mA cm^-3, compared to GAC without metal impregnation, up to 1.1 mA cm^-3. In MES, metal impregnated GAC enhanced acetate production rates compared to control GAC, up to 241 mg/L d^-1. The differences were mostly affected by the mass percentage of the metal catalyst on GAC, while the oxidation state of the metal had no considerable effect. Overall, impregnating GAC with metals shows high potential for improving the MES performance.

Keywords: Carboxylate production; Hydrogen evolution; Metal catalysts; Oxidation state.