a goldmine in the city

8/14/2019 A Goldmine in the City

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A Goldmine in the City

http://web-japan.org/nipponia/nipponia45/en/feature/feature12.html

There is a treasure trove of gold and rare metals in discarded cell

phones and computers. Japan has few mineral resources, so just think

if all that treasure could be recycled. The attempt is now being made.

Written by Takahashi Koki Photos by Sakai Nobuhiko

With collaboration from the National Institute for Materials Science (NIMS), Tanaka

Kikinzoku Kogyo K.K., and Dowa Holdings Co., Ltd.

Discarded cell phone parts—a mound of “urban ore.”




Japan, the Land of Gold.” How True Is the

Old Legend?http://web-japan.org/nipponia/nipponia45/en/feature/feature13.html

Left: IC chips from discarded electronic goods. The chips will be soaked in

nitrohydrochloric acid to dissolve the gold. The solution is electrolyzed to obtain a




gold that is 99.5% pure (center photo). This is electrolyzed again, then heated to

melt it (right). The final product is 99.99% pure.

The big sacks lined up in one corner of the facility are full of cell

phones, computer motherboards, IC chips and other items taken fromdiscarded consumer electronic goods. At first glance they look like they

are ready for the dump, but no—they are actually a potential gold

mine, yielding several hundred grams of almost 100% pure gold per

ton.

Most gold is kept as bars or jewelry, but things are changing. Sometime ago, electric and electronic industries began using gold to plate

certain components. Before long, they were using gold on IC chip

electrode surfaces and connecting the electrodes with gold wires. A

more recent innovation is golden vapor-deposited film on recording

media surfaces. So today, industries use a surprising amount of gold.

How much gold is stored away in such forms? Dr. Harada Komei of the

National Institute for Materials Science (NIMS) says, “We’re assuming

6,800 tons, in Japan alone.” That would represent 16% of the

mineable gold deposits worldwide, and more than the deposits in

South Africa, the biggest gold-producing country on the planet.

If the world keeps using rare and precious metals, or iron or copper for

that matter, at the same pace as before, they will all be used up one

day, just as oil will be. This is why attention is turning to “urbanmining,” which means collecting valuable components from no-longer-

used products all over Japan, and recycling their metals, especially the

rare and precious ones.




Today’s cell phones would not function well without gold parts. Above: Crystal oscillator covers. They come in different shapes and sizes.

Left: Wire used to connect IC chip electrodes.

“Urban mining” is being pioneered by metal refining companies. They

have started collecting and recycling components that contain gold,

silver, and rare and precious metals like platinum and palladium. Thefacility mentioned at the beginning of this article is retrieving gold that

is 99.99% pure, using chemical and electrolytic processes on the“ore.” They get more than 500 grams of gold for every ton of

components.

But it certainly is not easy to start up an “urban mine.” For one thing,

although tens of millions of cell phones are taken out of service everyyear in Japan, only about one-third are collected for recycling. Dr.

Harada and his fellow researchers studying resources and material

recycling say the recycling industry really needs to find ways to collect

unwanted electronic goods from homes, companies and factories, so

that their circuit boards, IC chips and other valuable components can

be recovered.




Electronic Scrap Refining

Within our Electronic Scrap Refining Division, we process largeamounts of electronic scrap from both the private and public sector in

a highly efficient and environmentally safe way.

All of our practices fall within the standard guidelines

set forth by the EPA. In addition, we provide our clientswith Certificates of Destruction / Recycling,

certifying that the reclamation and destruction /

recycling employed by our properly licensed facilities isin accordance with applicable federal regulation 40 CFR.

At CJ Environmental, our efficiency in refining allows our clients to getmore for their Electronic Scrap. We refine and recycle the following

materials:

Printed Circuit Boards

Processors

Computer Chips

Semiconductors

Gold Finger Scrap

Gold Plated Circuit Board Scrap

Populated Circuit Board

SIM Scrap / Smart Card Scrap

Mixed Scrap Integrated Circuits (IC chips)

Sorted Integrated Circuit (IC chips)

a goldmine in the city

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