Abstract Summary
Lithium-ion batteries have conquered a central role in today’s economy and way of living due to the need for reliable portable devices and the growing electric vehicle industry. This brings along serious ecological issues related to the disposal of these batteries and the prospection of chemical elements, such as lithium, nickel and cobalt used in their production, which calls for the need to recover and repurpose these chemical elements from used batteries. However, the recycling processes for lithium-ion batteries employed nowadays are not environmental-friendly. [1] Aluminosilicates have been known for their excellent adsorption capacity for several metals and may effectively be used as wide scale adsorbents to recover metals used in lithium-ion batteries with a minimal ecological impact. [2] Nonetheless, this feature can be improved through tuning of their textural and chemical properties. This research aims to enhance the adsorption capacity of aluminosilicates derived from lithium prospection, namely bentonite, by employing various chemical functionalization processes to optimize the recovery of elements such as nickel and cobalt. The prepared materials were tested on the adsorption of cobalt and nickel under different experimental conditions. The kinetic time for the experiments was determined to be 24 hours. The presence of nitrogen groups has improved the adsorption behaviour of the aluminosilicate materials at pH 3, and these materials have shown some selectivity, presenting higher affinity for the element nickel. The untreated aluminosilicates presented a maximum adsorption capacity for nickel of 29 mg g-1. When nitrogen groups were introduced to the surface of the materials, the maximum adsorption capacity increased to 44 mg g-1. As expected, the materials present the best adsorption behaviour at the highest pH values. Desorption studies were performed, resulting in a high recovery rate of the desired elements. This research proves the ability of surface-modified bentonite in metal recovery from liquid battery waste. Acknowledgments The authors acknowledge the financial support of the project NGS, with the reference n.º C644936001-00000045, co-funded by Component C5 – Capitalisation and Business Innovation under the Portuguese Resilience and Recovery Plan, through the NextGenerationEU Fund. References [1] Zeng, X. el al. (2014) “Recycling of Spent Lithium-Ion Battery: A Critical Review”, Critical Reviews in Environmental Science and Technology, 44:10, 1129-1165, DOI: https://doi.org/10.1080/10643389.2013.763578 [2] Urbanska, V. (2020) “Recovery of Co, Li, and Ni from Spent Li-Ion Batteries by the Inorganic and/or Organic Reducer Assisted Leaching Method”, Minerals, vol. 10, no. 555, DOI: https://doi.org/10.3390/min10060555
