JOHANNESBURG (miningweekly.com) – New Year reports of Japanese scientists achieving a synthetic palladium breakthrough have been greeted with scepticism.
Researchers at Kyoto University say that the new palladium-like alloy has been created by fusing ultramicroscopic spray particles of rhodium and silver.
Although each particle is a tiny ten nanometres in diameter, lead research Professor Hiroshi Kitagawa has told the Yomiuri Shimbun newspaper that the alloy has palladium properties.
Johnson Matthey GM market research Peter Duncan tells Mining Weekly Online that Johnson Matthey’s research centre has seen the Japanese patent application, which has been filed only in Japan.
“It does look like they have managed to create ‘nanoparticles’ – an often abused phrase – of rhodium and silver, which would not normally be achievable using traditional melting techniques,” Duncan says.
Impala Platinum group marketing executive Derek Engelbrecht tells Mining Weekly Online that he has asked Implats’ Japanese office to check out the report – “but using rhodium to make synthetic palladium sounds a little daft to me”, Engelbrecht adds.
Anglo Platinum marketing executive Sandy Wood also queries the logic of relying on rhodium to obtain palladium, as palladium is available in considerably larger quantities than rhodium is.
Potential applications remain rather vague. While the Japanese scientists do cite hydrogen storage as one potential use, the new alloy is unlikely to be commercially viable any time soon, given that it has only one half of palladium's hydrogen storage capacity.
“Nor indeed is palladium widely used yet anyway in hydrogen storage,” says Duncan.
The Japanese researchers also claim the alloy can serve as a catalyst, but again there is nothing to substantiate that it may be a commercially viable alternative to existing technologies.
“Without wishing in any way to dismiss the work, it is very common for Japanese academics to patent anything vaguely new, regardless of its potential in the commercial world,” Duncan adds.
The researchers used nanoprocessing technology to heat water solutions containing equal parts of rhodium and silver, turned the solution into a mist, and slowly mixed it with heated alcohol to produce particles of the new alloy.
Rhodium, palladium and silver have close atomic numbers that determine their chemical characterisations – 45, 46 and 47 respectively.
"The orbits of the electrons in the rhodium and silver atoms probably got jumbled up and formed the same orbits as those of palladium,” Kitagwa has been quoted as saying.
Soft, ductile, white and tarnish-resistant palladium, which occurs naturally with platinum, especially in gold, nickel, and copper ores, is able to absorb significant quantities of hydrogen.
Japanese researchers concede that the new alloy will be difficult to produce commercially, but envisage using the same production method to develop synthetic rare earths, which are currently in great demand.
China produces 97% of the global supply of rare earths, which are used in computers, wind turbines and electric cars.
But China has announced that it will be cutting the export of its rare earths by 35%, which has forced the world to scramble for alternative sources of rare earths.
The Japanese response has not only been to attempt to create the metals they need artificially, but also to find alternative global sources.
US-based Molycorp is restarting the Mountain Pass mine with the help of Japanese investment, the ASX-listed producer Lynas has signed a long-term rare-earths supply agreement with a Japanese consumer, and the South Korean government says that it will cooperate with Japan in establishing new sources of rare earths in Vietnam, Australia, Kyrgyzstan and South Africa.
In South Africa’s Western Cape, a bankable feasibility study is at an advanced stage at Steenkampskraal, where monazite deposits are expected to give rise to one of the first new rare-earths mines outside China.
Great Western Minerals is developing Steenkampskraal, which is a former high-grade producer with a known process for recovering rare earths.
The World Trade Organisation (WTO) will not publish a ruling in a dispute brought against China until April, which is more than the usual six months stipulated.
The WTO says, however, that all the parties in the dispute have agreed to the extended time period.
Japan's Trade Minister Akihiro Ohata wants to visit China soon to talk to officials about securing ongoing supplies of rare earths.
"I'd like to make sure future supply of rare earths in volume terms will not affect the industry here," Ohata says.
Japan imported 20 000 t of rare earths from China last year.