No. 709: Reducing the cost to recover rare metals to less than half of the current level (April 30, 2013)

Technology:

Dr. Yasuhiro Konishi of Osaka Prefecture University developed a technology to recover platinum and vanadium efficiently from catalysts of vehicle gas emission equipment using bacteria in alliance with Hidaka Fine Technologies. The new technology can reduce the recovery cost to less than half of the current level. They crumbled catalysts and dissolved them using chemical, and add special bacteria that bring in metals. In an experiment, they successfully recovered 99% of rare metals including platinum from a 50 ml solution in three hours. Traditionally, it was necessary to heat the solution up to 1,300 degrees centigrade using electric furnace. The new technology eliminates the necessity of heating and reduces the recovery cost to less than half of the current level. They wish to put it into practical use in three years.

He also developed a technology to recover lithium and manganese from lithium-ion batteries in alliance with Toray Engineering. They added bacteria into the solution that contain manganate lithium. Iron ions given electrons by the bacteria dissolved almost all lithium and 85% of manganese and aluminum. Dissolved metals can be recovered by resin. The new technology can reduce the recovery cost considerably.

Dr. Junji Shibata of Kansai University developed a technology to recover rare metals in alliance with Nippon Recycle Center. They added methanol to the solution that contains lithium ions to recover lithium. Although about 20% of lithium deposits, they added methanol and sodium hydrate to the solution to reduce the solubility. And they successfully made 95% of lithium deposit.

Reusable metals contained in waste home electronics and mobile phones are called urban mine. National Institute for Meal Science reckons that Japanese urban mine has about 6,800 tons of gold, 60,000 tons of silver, and various kinds of rare metals. In particular, the amount of indium and tantalum is estimated to exceed 10% of world resources. Because of the high recovery cost, the recycling rates of gold, palladium, platinum, and rhodium were 40%, 38%, 19%, and 7% respectively in 2008. The race to develop a technology for efficient recovery of rare metals will grow fiercer.

Major methods to recover rare metals

Research laboratory	Approach
Osaka Prefecture University	Recover platinum and palladium in a solution using bacteria
Osaka Prefecture University	Dissolve lithium, manganese, aluminum in a solution using bacteria
Kansai University	Deposit lithium using methanol
Morishita Jintan	Recover rare metals from plant effluent using fine capsules
Iwate University	Recover samarium using boric oxide

Recovering rare metals from home electronics 

and mobile phones grows widespread.