Mining platinum and platinum group metals such as nickel, copper, and
iridium is a difficult process. Mining for these ores alone is difficult
as they only exist in small quantities around the world. Most of the
platinum exists in trace amounts around the world and is very difficult
to extract since it doesn’t exist in dense concentrations and mining for
it would result in a loss of money. A new technique is being developed
by researchers that utilize plant’s absorption of minerals in the
ground. The plants would absorb the platinum and platinum group metals
into their cells which would then be processed and the metals would be
extracted. This method of extraction is very efficient compared to
mining extraction processes. The yield is not as large but the yield
percentage is much higher. Professor James Clark, the Director of the
Green Chemistry Centre of Excellence at York, says "The trick is to
control the decomposition of the plant in a way which keeps the metal in
its nano-particulate or catalytically active form. Catalysis is being
used more and more in industrial processes and particularly for emission
control because of the demand for cleaners cars, so 'phyto-mining'
could provide a sustainable supply of catalytically active metals."
Specific species of plants such as willow, corn and mustard have adapted
over enough time to develop a resistance to being affected by these
platinum group metals and are able to absorb relatively large quantities
of these metals.
This is connected to Advanced Chemistry because the process the plants use to recover platinum and
redeposit the minerals as nanoparticles in plant cells is also helping
researchers and chemists to observe mechanisms involved in processes
such as this. Using these mechanisms, the scientists will have better ideas on extracting metals from mine tailings that are currently uneconomical to recover. Thus, once again the mechanism of a process (not exactly just one reaction) is important.
