New technology dramatically increases the recovery rate of precious metals from waste
Manufacturing process and the physical / chemical structures of the gold recovery material. Source: Korea Institute of Science and Technology (KIST)
In South Korea, which relies on imports for 99.3% of its metal resources, per capita consumption of metal resources is the highest in the Organization for Economic Co-operation and Development, and consumption of expensive metals in industries such as renewable energy, Healthcare and semiconductors are on the rise. Gold is demanded for applications such as batteries, electric vehicles and renewable energy in the electrical and electronics industries, but is a large industry variable due to limited availability and high cost. Therefore, research on urban mining, which extracts precious metals from waste, is actively conducted around the world. However, most technologies for extracting high purity gold from waste resources require many chemicals and high operating temperatures; therefore, it has regulatory and efficiency problems.
A Korean research team has developed technology that can significantly increase the recovery rate of precious metals from waste. The research team, comprised of Drs. Jae Woo Choi and Dr. Kyung-Won Jung from the Center for Water Cycle Research at the Korea Institute of Science and Technology (KIST), reported that they have developed a gold recovery process with the highest recovery efficiency in the world. at 99.9%. The technology is a capsule type material in which a polymeric shell surrounds a multi-layered internal structure.
The developed material has the advantage of high healing efficiency compared to conventional adsorption materials because the material traps gold ions inside the capsule for healing. The material also has the advantage of preventing clogging of the internal porous structure because the polymeric shell allows gold ions to penetrate while not penetrating the suspended solids containing gold. By introducing functional groups that react only with gold ions in the multi-layered internal structure, gold that has passed through the polymeric shell can be firmly recovered despite the coexistence of 14 types of ions and 3 types. types of suspended solids. Capsule-type material can be produced through a continuous process based on the solvent exchange method, and its efficiency and strength are demonstrated by maintaining a recovery performance of 99.9% or more even when the material reused 10 times.
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The concept of gold recovery in the material (left) and its performance (right). Source: Korea Institute of Science and Technology (KIST)
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(From left) containing liquid gold, a capsule-type material wrapped in a round polymeric shell (white) made by KIST researchers to recover gold in an eco-friendly method, gold extracted through the recovery process, and extracted gold is pure high-purity gold. Credit: KIST
The authors write, “The material developed through this research solves the problems of conventional materials developed for the recovery of precious metals. In addition, it can be used immediately in relevant industrial processes because it can be easily synthesized in large quantities. Through this study, it is clear that the chemical properties and morphology of the recovered material may also play an important role in the recovery of metal resources from water. ”
The lead author, Dr. Youngkyun Jung of KIST, said, “The results of this research are expected to serve as a basis for developing Korea’s first eco-friendly process that can selectively recover and refine metal resources from waste and valuable. Metal scrap. created in a variety of industries, such as automobiles and petrochemicals. “
The research results are published in the latest issue of Journal of Chemical Engineering.
Improvement of high durability single-atomic catalyst using industrial humidifier
Youngkyun Jung et al, Cage-like amine-rich polymeric capsule with internal 3D center-radial channels for efficient and selective gold recovery, Journal of Chemical Engineering (2022). DOI: 10.1016 / j.cej.2022.135618
Provided by the National Research Council of Science & Technology
Citation: New technology dramatically raises recovery rate of precious metals from waste (2022, May 17) retrieved 17 May 2022 from https://phys.org/news/2022-05-technology-recovery-precious -metals.html
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