Jacob Rubel of KU Leuven and colleagues from KU Leuven, China and the Czech Republic has published a new article entitled Modified porous carbon from waste printed circuit boards for enhanced adsorption of carbon dioxide in abandoned mines. The article is published in the Journal of Environmental Chemical Engineering Volume 13, Issue 2, April 2025.
Waste printed circuit boards (PCBs) present significant environmental challenges due to their toxic and varied composition. Current recycling methods focus on metal recovery, leaving nonmetals underutilised. This study converts such nonmetals into nitrogen-doped porous carbons with high carbon dioxide adsorption capacity. Waste PCB and pure epoxy samples were processed through milling, sieving, mixing with KOH and urea, and activation in a tubular furnace. Scanning electron microscope images confirm the presence of glass fibres in PCB-derived carbon, resulting in smaller pore development than in the epoxy-derived activated carbon. Nitrogen adsorption analyses reveal that PCBs activated at 700 °C exhibit lower surface area (180 m2/g) and micropore volume (0.07 cm3/g) compared to pure epoxy (1381 m2/g and 0.58 cm3/g, respectively). CO2 adsorption capacity (20 °C, 1 bar) is highest for epoxy-derived carbon (2.30 mmol/g), decreasing for PCB-derived carbons from 1.62 mmol/g to 0.06 mmol/g with increasing activation temperature (600–800 °C). PCB-derived porous carbon does show greater affinity for CO2 than the epoxy derived carbon through a higher isosteric heat of adsorption (approx. 24 kJ/mol vs approx. 16 kJ/mol) and higher amount of CO2 adsorbed per surface area surface area (3.3 µmol/m2 vs 1.7 µmol/m2). These carbons offer potential for enhanced CO2 storage in abandoned mines, providing a sustainable solution for PCB waste management and CO2 emission mitigation.
Reference
Jacob Rubel, Xinyu Guo, Dharmjeet Madhav, Sammy Verslype, Junjian Zhang, Yukun Ji, Pavla Eliášová, Veerle Vandeginste, Modified porous carbon from waste printed circuit boards for enhanced adsorption of carbon dioxide in abandoned mines, Journal of Environmental Chemical Engineering, Volume 13, Issue 2, 2025, 115790, ISSN 2213-3437, https://doi.org/10.1016/j.jece.2025.115790.
Acknowledgement
This research was supported by KU Leuven Internal Funds Bijzonder Onderzoeksfonds 2020 (grant number STG/20/013), the National Natural Science Foundation of China 542307202), the Natural Science Foundation of Jiangsu Province (BK20221135) and Xuzhou Science and Technology Plan Project (KC23427). We are grateful to Jan Poelaert (KU Leuven, Campus Brugge) who advised and contributed printed circuit board waste materials for this study.
