New applications for gold to fuel growth
Ciaran Ryan
Posted: Wed, 11 Apr 2007
miningmx.com
[miningmx.com] -- RESEARCH by Mintek's AuTEK project – set up to develop new applications for gold – suggests the yellow metal is far more versatile than was originally thought. Researchers have come up with some astonishing new uses for gold in healthcare, auto-catalysts and nano-technology.
Gold producers have long eyed platinum’s strong industrial demand with envy. Nearly 70% of the 3 361 tons of gold produced worldwide in 2006 went into jewellery and less than 14% to industrial applications.
Jewellery accounts for just a quarter of the global annual platinum demand, as against 60% for auto-catalysts. The strength of industrial demand for platinum goes some way to explaining the resilience of the platinum price, up 180% since 2002, compared to 120% for gold.
Gold’s dependence on jewellery demand is its Achilles heel. Jewellery demand is more sensitive to fluctuating economic conditions and this has an effect on the price of the metal itself. Jewellery demand for both platinum and gold fell in 2006 in response to higher metal prices. Despite near record prices for platinum, demand from auto-catalyst manufacturers increased 14% last year as European and global vehicle emission standards become ever stricter.
Exciting possibilities in the field of nano-technology
In 2000, Mintek and AngloGold Ashanti set out to develop more industrial uses for gold, culminating in the creation of the AuTEK Project. Gold Fields and Harmony have subsequently joined the project. Gold has many unique physical and technical attributes, such as catalytic properties that, unlike platinum, continue to function at low temperatures.
Its malleability and distinctive electronic structure have opened exciting new possibilities in the field of nano-technology and in the use of advanced materials. Some of the most encouraging research is taking place in the biomedical field, due to gold’s excellent biocompatibility and lack of toxicity to the body. New treatments for malaria, AIDS, rheumatoid arthritis and even cancer are now developed, due largely to the work of Project AuTEK, which acts as the co-ordinator of gold biomedical research in SA.
“Twenty to 40 years from now, the industrial uses for gold could match the current demand for jewellery,” says Dr Gary Pattrick, chief scientist for precious metals at Mintek. This suggests the gold market will be less prone to the volatile swings of jewellery and speculative demand.
Project AuTEK’s biomedical programme, a collaborative effort between Mintek and various local universities, has tested and screened more than 200 novel metal-based compounds against various tumour cell-lines, resulting in the identification of a number of highly potent classes of compounds.
“Drugs used in the treatment of cancer traditionally used platinum, but now a number of gold-based compounds have been found to exhibit complimentary therapeutic value, justifying further research in the area, ” says Dr Judy Caddy, head of Project AuTEK Biomed.
Structural modification of key compounds identified has resulted in higher tumour selectivity and efficacy, and preclinical preperations are now underway. Gold-based compounds have also been screened as anti-HIV and anti-malaria agents, where more detailed pharmacological studies are now underway.
Research on gold catalysts has likewise come up with some encouraging findings. Gold was previously considered too inert and noble to provide active surfaces for catalysing chemical reactions. However, it has recently been shown that if the metal is sufficiently dispersed, it has potent catalytic properties, easily converting carbon monoxide into carbon dioxide, even at temperatures as low as -70 degrees Centigrade.
This makes gold the most active known compound in the removal of this toxic pollutant from the atmosphere. Gold’s catalytic properties at low temperatures and in the presence of water further enhance its use as a catalyst in humid conditions. Mintek is upgrading its gold catalyst pilot plant to handle 65kg of material per batch and is now searching for partners to further develop its AuroPureH2 catalyst, which has the advantage of being able to catalyse the removal of carbon monoxide from slightly dirty hydrogen that would otherwise deactivate a platinum-based catalyst. This opens the potentially huge fuel-cell market to gold producers.
Pattrick says this catalyst will complement rather than replace platinum catalysts in PEM (proton exchange membrane) fuel cell systems.
Yet another area of focus is nano-technology, which deals with miniscule amounts of matter. The properties of matter on the nano-scale differ considerably from those of the bulk material, and gold has been found to have some extraordinary applications in fields such as bio-labelling, where it’s used for medical diagnostics and electro-chemistry. The number of potential applications flowing from this research is vast, particularly in the field of medical diagnostics, testing and treatment, says Dr David Crompton, a senior engineer at Project AuTEK.
A bilateral agreement for general nano-scale R&D collaboration is being finalised with Japan's National Institute for Materials Science. |
