Posted: 05 Jul 2011 02:28 PM PDT
I just want to celebrate, yeah, yeah! A Japanese expedition has discovered a wealth – literally – of rare earth minerals in mud samples taken from the floor of the Pacific Ocean. Should the discovery pan out, the rewards could be richer than gold. Even better, refining the bounty involves much more environmentally friendly processes compared to those used in highly toxic traditional mining.
Trash to Treasure
A stunning discovery by a Japanese research team could ripple the waters of science, technology and geopolitics for years to come… “ripple” being the key word as the report concerns samples of seafloor mud dredged from thousands of feet beneath the surface of the Pacific Ocean.
Mud, you say? Indeed, the gooey gloop that’s been accumulating for millions of years harbors an unseen but much desired treasure: rare earth minerals, said by some to be “21st-century gold” based on their rarity and value. These attributes are a function of demand, which has been on the rise due to the explosion of new, high-tech products and applications requiring these formerly uncommon elements.
Now just to clarify, “uncommon” refers to concentrated deposits of rare earth minerals suitable for commercial mining. The elements themselves (the metals Scandium and Yttrium, plus 17 minerals in the Lanthanide series of the Periodic Table) are relatively common components of the earth’s crust – Cerium, for example, is about as common as Copper.
The three rare earth elements mentioned above are joined by Lanthanum, Praseodymium, Neodymium, Promethium, Samarium, Europium, Gadolinium, Terbium, Dysprosium, Holmium, Erbium, Thulium, Ytterbium and Lutetium. Their atomic numbers range from 57 through 71 inclusive, plus 21 for Scandium and 39 for Yttrium. Besides sharing similar properties, many of the rare earths have similar names derived from the Swedish village of Ytterby, where rare earths were first identified in the early 19th century.
Rare Earths, Abundant Uses
(image via: Allvoices)
Before we delve into the particulars of the Japanese ocean discovery, let’s take a look at the many uses of rare earths and why they’re so important today, as opposed to 100, 50 or even 10 years ago. Can you imagine living without your cellphone, MP3 player or other portable electronic devices? What would the modern world be like without hybrid vehicles, flat-screen TVs, night vision goggles, superconducting magnets or anything made by Apple?
Pretty grim, huh? What’s even grimmer is knowing that 97 percent of the current supply of rare earth minerals is controlled by a single nation, China, and boy oh boy do they know it! Annoy China and you just might see your rare earth imports cut to the bone… and by “you”, we mean Japan.
In November of 2010, an incident occurred in the East China Sea near the disputed Senkaku Islands (Japanese) or Diaoyu Islands (Chinese). While attempting to stop and arrest the captain of a Chinese fishing boat deemed to be trespassing, a Japanese Coast Guard vessel was rammed by the Chinese ship. Check out this video captured by a Japanese crewman and leaked without authorization:
Amid the diplomatic fallout caused by Japan’s taking the Chinese trawler captain into custody, rare earth exports from China to Japan dropped precipitously and remained at lower than normal levels for months. As Japan is a major manufacturer of leading edge electronics and hybrid vehicles, shortages of rare earth elements would be expected to seriously affect these industries while those in China enjoyed unrestricted access to these crucial raw materials. Japanese companies have accelerated rare earth recycling programs but these worthwhile efforts are stopgaps at best. How did we arrive at such a situation?
When one considers mining for rare earths, the NIMBY factor comes into play in a big way. Put plainly, a rare earth mineral mine is about the last thing you’d want in your backyard. Separating the minerals from the waste products involves the use of toxic chemicals and produces particulate pollution on a massive scale. The waste itself is toxic – rare earths are often found in conjunction with radioactive elements such as Uranium and Thorium.
Voters in the United States and Australia – two nations with large reserves of rare earth minerals – simply won’t tolerate rare earth mining. China, on the other hand, has a totalitarian form of government that puts the needs of China as a whole before those of the “voters”. Even so, there have been rumblings from farmers and agricultural cooperatives in China’s rare earth mining and smelting regions whose crop yields have plummeted as a result of extensive pollution.
One of the stated reasons China has reduced its exports of rare earth minerals is due to these environmental concerns, though many China-watchers dismiss this as green-washing to hide the real issues: Chinese strategic control over rare earth minerals and the prices charged for them.
Some might say that rare earth importers have only themselves to blame for the current supply imbalance, and that may indeed be true. There’s the moral issue to consider as well: while we enjoy our iPhones and Prius’s (Prii?), millions of poor Chinese farmers suffer from ill health and reduced quality of life. Wouldn’t it be nice if somebody could find an abundant source of these essential minerals and a cheap, easy and non-polluting method of refining them?
Bounty From the Sea
(image via: CBC)
A recent announcement published in Nature Geoscience would seem too good to be true, which is perhaps why the researchers behind the story ensured that their testing was both vigorous and voluminous in scope before revealing their discovery. According to the researchers, led by Yasuhiro Kato of the University of Tokyo’s department of systems innovation, “Just one square kilometer (0.4 square mile) of (oceanic rare earth) deposits will be able to provide one-fifth of the current global annual consumption.”
Professor Kato and his team tested over 2,000 sediment samples retrieved from the seafloor at 78 different sites in the central Pacific Ocean – in international waters, one might add. It gets even better: the oceanic rare earth deposits are nearly twice as concentrated as underground deposits in China and they boast a higher ratio of heavier to lighter rare earth elements. Serendipitously, heavier rare earths are more important than lighter minerals in manufacturing technology products.
Since the oceanic rare earths are suspended in viscous mud and not locked into solid rock, refining them would be a simpler process. No need for blast furnaces or the strong acids that have wreaked so much environmental havoc around land-based mines. Radioactivity from associated trace elements is not a concern as the Japanese researchers measured their occurrence at just 1/5 that of typical underground ores. What’s more, these rare earths are anything BUT rare. According to professor Kato, rare earths contained in the seafloor deposits could amount to 80 to 100 billion metric tons. Estimated global reserves confirmed by the USGS for all land-based sources including China only total 110 million tonnes. Investors may not be happy to hear this news but just about everyone else should be!
The only fly in the ointment is bringing the rare earth-infused sea mud to the surface in quantity. The researchers’ samples were extracted from cores ranging from 11,500-20,000 ft (3,500 to 6,000 meters) below the ocean surface. Where there’s a will there’s a way, however, and necessity is the mother of invention after all. “Sea mud can be brought up to ships and we can extract rare earths right there using simple acid leaching,”stated professor Kato. “Within a few hours we can extract 80–90 percent of rare earths from the mud.” Sounds like a plan!
The possibility of cheap, abundant, pollution-free rare earth minerals is as exciting as the prospects of low-cost, sustainable and renewable solar power… though the latter still lurks somewhere in the future. At least there’s hope, both for consumers and for China’s long-suffering farmers and rural villagers. The day may come when, like the 1970s funk-rock band Rare Earth, we all can celebrate another day of living, another day of…LIFE!