Projects / Programmes
Study of novel environmentally friendly noble metals recycling process based on reactive gas or liquid induced surface electrochemical potentials.
| Code |
Science |
Field |
Subfield |
| 2.02.04 |
Engineering sciences and technologies |
Chemical engineering |
Catalysis and reaction engineering |
| Code |
Science |
Field |
| P401 |
Natural sciences and mathematics |
Electrochemistry |
| Code |
Science |
Field |
| 2.04 |
Engineering and Technology |
Chemical engineering
|
Recycling, corrosion, electrocatalysis, precious metals, electrochemistry, reaction engineering
Researchers (1)
| no. |
Code |
Name and surname |
Research area |
Role |
Period |
No. of publicationsNo. of publications |
| 1. |
30470 |
PhD Nejc Hodnik |
Materials science and technology |
Head |
2017 - 2019 |
383 |
Organisations (1)
| no. |
Code |
Research organisation |
City |
Registration number |
No. of publicationsNo. of publications |
| 1. |
0104 |
National Institute of Chemistry |
Ljubljana |
5051592000 |
21,007 |
Abstract
In the proposed project lead researcher dr. Hodnik will on the fundamental and applied level deepen the knowledge about the new way of precious metal dissolution that was recently published in a prestigious journal Nature Communications (also patent pending) where dr. Hodnik used his knowledge on platinum as electrocatalyst degradation for completely new way of dissolution (Nat. Commun. 7, 13164 doi: 10.1038/ncomms13164 (2016)). This breakthrough has opened up a whole new perspective in the field of corrosion electro-chemistry, which can be used for recycling purposes (hydrometallurgy) and also for the understanding and improvement of catalysts and other products containing precious metals. Also new non-gradient measuring reactor, which will allow accurate monitoring of the dynamics of dissolution of the precious metals (on-line UV-VIS detector) and consumption of gaseous reagents (on-line FTIR detector).
For this purpose the lead scientist will use the equipment at the National institute of chemistry that will be for example used to monitor the dissolution of precious metals with extreme precision together with electrochemical potential measurement (electrochemical flow cell coupled with ICP-MS) and visually monitor the changes of precious metal morphology, structure and composition at the atomic scale (identical location and in situ liquid electron microscopy). Conditions of the measurements in non-gradient reactor will be adapted so that transport phenomena will be minimized (the reaction rate will be independent of the stirring speed enabling the measurements of the dissolution kinetics). With these techniques and methods and others (XRD, XPS, BET. ..) Dr. Hodnik will gain new insights into the dissolution of precious metals together with the knowhow about the operating conditions of potential commercial recycling reactors.
The project is not only important for the development of science or a scientific field however has a direct application in the circular management of precious metals, which already represents a pressing global problem. Europe for example exports 75% of its end of life electrical and electronic equipment (7.5 million tons annually) that also contains precious metals to the third world countries. The increasing demand for high-tech, advanced, green and IT products containing precious metals will lead to the depletion of the precious metals resources in the future. Since the current recycling technologies are based on extremely aggressive and "dirty" chemistry that is environmentally unfriendly and harmful to health the need for a new, clean and sustainable process is of high importance.
The overall scientific goal of this project is to gain an improved understanding of the reactive gases or liquids induced new nnon-thermodynamic kinetically controlled electrochemical dissolution of precious metals (PMs) with further aim of employing the collected knowledge in the design of a recycling reactor.
Significance for science
Since leaching and general corrosion is electrochemical in nature it would be only natural that electrochemical approach of finding new dissolution strategies would be utilized. This was unfortunately however not the case in the most of the studies till now. Electrocatalysis is recently gaining in popularity as more and more scientists are recognising its potentials. Aqua regia, as state-of-the-art process, was known already in 14th century and uused by alchemists. Therefore project leader sees great opportunity in combining the knowledge of corrosion and electrocatalysis, especially in stability of NM electrocatalysts, which is his expertise, where the basic approach would be reversed from increasing corrosion resistance to decreasing it. This is perfectly exemplified in his recent publication in the prestigious journal of Nature Communications titled "Platinum recycling going green via induced surface potential alteration enabling fast and efficient dissolution" (Vol. 7, 2016, 13164).
Since also other precious metlas exhibit transient dissolution [ChemCatChem 2014 6, 2219], there is a urgent need to, firstly, show that the principle efectively works also for other metals, secondly, explore and sturdy dissolution mechanisms and reaction kinetics and, thirdly, to perform reactor demonstration pilot project that will enable complete dissolution of precious metals from real samples. Thus, the contribution on the fundamental level is expected since the mechanism of transient dissolution is still far from beeing resolved and understood. This demands developement of a new characterisation techniques and methods. which is the core of the proposed project.
This will be important not only for the purposes of the dissolution (recycling), but also for purposes of understanding the stability of the precious metal catalysts. This is the expertise that Dr. Hodnik together with the Department of Chemistry material (Head prof. Miran Gaberšček) and the Department of Analytical Chemistry is investigating now for several years. On this subject he has published mostly as a corresponding author more than 15 articles in A1 journals among which two in 2016 were published in the journal of ACS Catalysis (impact factor 9). Understanding why a particular catalyst dissolves will be helpful in the planning of new materials, or to understand the conditions that are potentially harmful for a particular precious metal catalyst.
Significance for the country
Recycling of NBs is a multi-billion-euro business. According to United Nations Environment Program (UNEP) gold, silver and palladium are rarely recycled in Europe. Every year around €5 billion are lost in this way. The massive growth in the manufacture of electronic products means that this waste of resources threatens to grow even greater, the UNEP report continues. Future technology involving fuel cells or photovoltaic cells and other electrical and electronics equipment will further increase the need for these metals. Sales of mobile telephones reached a billion in 2007. Other important NMs containing product is catalytic converter, which is used with every internal combustion engine. Automotive industry is one of the world's most important economic sectors by revenue. With exhaust emissions standards getting stricter catalytic converter are gaining in importance. It was just recently announced that China will introduce higher environmental standards for vehicle exhaust by an average of 50% a year. Now, even if in the future combustion engine vehicles will get replaced by electric cars it is high probable that some of them will be powered by fuel cells that also contains platinum. Here only few examples were mentioned, however already these show the enormous socio-economic and culturally relevance of the near future recycling technology. Thus has the proposed project with a new sustainable way of recycling a great potential to significantly impact the economy and society in the future.
The unavoidable transition from linear to circular economy will force all the countries of the European Union and thus also of Slovenia to start deal with their waste more efficiently. With this we will go towards the "zero waste" concept where all the waste will be treated as a raw material used for the manufacture of new products. For example value chain of recycling of precious metals in Europe and Slovenia from waste collection, processing and to production of products is incomplete. It is broken at the point of refining; this is the final processing of precious metals of higher purity. It is interesting that Slovenia already has a very good coverage and a large number of collectors of waste containing precious metals (Snaga javno podjetje, Blok, Dinos, Gorenje surovina družba za predelavo odpadkov, Zeos, etc.). At the same time Slovenia also has s also relatively large production of products containing precious metals (Hidria Keko, Iskra, Gorenje, Kolektor, Zlatarna Celje, many galvanizing plants, etc.). Therefore, the process proposed in the project presents a direct opportunity for Slovenia to invest in the new knowledge that would completes the chain of added value of waste recycling to precious metals. This could on a long run create new jobs, keep precious metals within the country, which would make it independent from the imports, and also help to reduce pollution and exploitation of third world countries where a lot of waste is beeing currently exported.
Most important scientific results
Interim report,
final report
Most important socioeconomically and culturally relevant results
Interim report,
final report
