Follow Slashdot stories on Twitter

 


Forgot your password?
Close
typodupeerror
×
Technology

The Royal Mint To Extract Gold From Old Phones (bbc.com) 39

Posted by msmash from the how-about-that dept.
Gold and precious metals are to be extracted from old phones and laptops by Britain's coin-maker. From a report: The Royal Mint plans to introduce a world-first technology to the UK to recycle gold from electronic waste. Fewer than one fifth of electronic waste ends up being recycled, estimates show. The mint's chief executive Anne Jessopp said the technology would help to "make a genuine impact on one of the world's greatest environmental challenges." The Royal Mint has signed an agreement with Canadian start-up Excir to recover 99% and more of gold from devices' circuit boards. It said the chemistry selectively targets and extracts precious metals from circuit boards in seconds.
This discussion has been archived. No new comments can be posted.

The Royal Mint To Extract Gold From Old Phones More

The Royal Mint To Extract Gold From Old Phones

Comments Filter:

  • Gold on circuit boards is nothing more than a thin coating (like atoms thin) and much of anything else is also just plated

    Theres actually very little metal in modern electronics most of the waste is plastic

    • Yes, it should be reuse, reduce, recycle. Lots of e-waste is still functional and reusable. It is a very toxic process to extract the small amounts of precious metals. This should be the very last stop once the electronics are dead and done.

    • Re:But theres hardly any gold in there (Score:5, Informative)

      by bobstreo ( 1320787 ) on Wednesday October 20, 2021 @10:56AM (#61910051)

      Gold on circuit boards is nothing more than a thin coating (like atoms thin) and much of anything else is also just plated

      Theres actually very little metal in modern electronics most of the waste is plastic

      There seem to be a lot of companies who accept "older" processor chips and are willing to pay for them.

      I got this from:
      https://www.chipsetc.com/gold-... [chipsetc.com]

      "Older computer chips, transistors & electronics components from the 1960's & 70's contain the highest gold content in general as they were often designed for military and aerospace applications which required them to have heavier gold-plated caps (lids) and leads / pins / connectors, which offered the component increased longevity, heat, radiation and corrosion resistance.

      During the 1990's some early ceramic versions of the Intel 386, Intel 486, Intel Pentium Processor, Intel Pentium Pro Processor, Motorla 68000 series, and many DEC Alpha (and similar RISC CPU's) had large gold-plated caps, connector pins, and internally had solid gold wiring making them good candidates for gold recovery.

      Up to around 1998, very fine solid gold wiring was used in wire bonding the computer chip (die) to the substrate packaging. Gold wire used in Integrated circuit packaging were typically 99.9% pure gold. All other components (caps, lids, pins & pads) were only gold-plated. Some manufactures have also used aluminum or copper wiring in the past in place of solid gold wiring to cut material costs.

      The Intel 386 and 486 ceramic CPU's currently are the highest price paid (per pound) for CPU's by the gold recycling companies. This is due to them having gold plated heat spreaders, and the amount of gold plated pins found on the underside of these CPU's, and smaller package size (less ceramic material used in the CPU's packaging per pound).

      Also, the Intel Pentium Pro Processor remains a top CPU desired by gold recyclers. It's gold contents are one of the highest of any mainstream CPU package from the 1990's to date, mostly due to it's much larger package size which contributes to a an increased number of gold plated pins, and much larger gold plated heat spreader cap. The Pentium Pro also had two separate chips inside so this doubled the amount of solid gold wire bonding that is usually found in a single chip CPU like the Intel 386 and 486 chips. Gold refining yields of the Pentium Pro have been reported to be as high as around .33 grams per CPU.

      Note: The larger package size of the Pentium Pro CPU also means there is more ceramic material per pound, which is why the Intel 386 and 486 CPU's command a higher value than the Pentium Pro."

      "List of Ceramic CPU's that have the Highest Gold Content

      gold pentium pro

      Intel Pentium Pro Processor

              Intel 186 / 286 / 386 / 486 / Pentium / Pentium Pro / i860 / i960

              Cyrix 486 / 586 / MII

              IBM 486 / 586 / 686

              Motorola 68000 / 88000 series

              NEC & Toshiba MIPS series: R4000 / R8000 / R10000 / R12000

              AMD 286 / 386 / 486 / K5 / 29000 series

              IDT Winchip C6 / 2A

              DEC Alpha

              HP PA-7000 & PA-8000 RISC series

              SUN SPARC / UltraSPARC / SuperSPARC RISC series"

    • Re: (Score:3)

      by e3m4n ( 947977 )
      Its substantial enough that Intel had a gold reclamation plant in their FABs. $60/g is still something. When my friend worked in that plant outside Phoenix, he told me they used hydrofluoric acid for the gold reclamation, and that you had to be extremely careful because it was a bone seeker and you didnt want that shit anywhere near your body. It just doesnt work as fast as Breaking Bad tried to make it look.

      • Re: (Score:3)

        by tragedy ( 27079 )

        It can dissolve your bones through your skin, but it's worse than that. It messes up calcium ion transport, which means that exposure can lead to heart failure.

  • It said the chemistry selectively targets and extracts precious metals from circuit boards in seconds.

    Selectively targets and extracts? Is there a standard bonding agent used to attach these metals? Because gold in particular is resistant to many things, and everything it reacts with seems to be harmful — and more relevantly, to react with lots of other stuff as well.

    How do they actually remove the gold?

    • Re: (Score:3)

      by pjt33 ( 739471 )

      Their US patent 2018/0112289 A1 is about as illegible as any modern patent, but it's an acid, an oxidising agent, and an organic solvent, and a whole smorgasbord of organic solvents is mentioned.

    • The standard as far as I know is Aqua Regia which dissolves gold, then the gold compounds are extracted from the solution and converted back to elemental gold.

    • Re:How? (Score:5, Informative)

      by EvilSS ( 557649 ) on Wednesday October 20, 2021 @10:38AM (#61909993)
      Just a guess, but considering the location of the research and the location of this company doing the extraction, as well as the description of it being very fast, I'd guess this is what they are going to use: https://www.jhunewsletter.com/... [jhunewsletter.com]

      https://www.jhunewsletter.com/article/2016/02/new-process-extracts-gold-from-electronics

      This is not the most recent advance in gold extraction, however. Recently, a research team discovered an efficient method of stripping gold from electronic wastes. Modern electronics contain very small parts that are powered by low currents. As a result, a reliable, corrosion-resistant metal is necessary for the devices to work. Therefore, most electronics contain trace amounts of gold that are bound to their internal components.

      However, extracting gold from electronics is difficult, and the amount of recovered gold from a single device is very low. Gold is a very non-reactive metal, which forces companies to use chemicals such as sodium cyanide to dissolve and extract gold. However, sodium cyanide is both environmentally damaging and expensive, making it unsuitable for stripping small amounts of gold from electronics.

      To avoid using sodium cyanide, the research team, led by Stephen Foley, an associate professor at the University of Saskatchewan, developed a method that relies on a combination of acids and oxidants. This solution consists of acetic acid mixed with an oxidant which, in the presence of another acid, dissolves gold at a record rate.

      In their experiments, gold from electronic circuit boards were dissolved in around 10 seconds. In a large scale study, 100 liters of the solution was capable of dissolving one kilogram of gold. Additionally, the fluid is cheap and more environmentally-friendly than sodium cyanide; a liter of this solution costs 50 cents and can be reused in subsequent extractions.

      This novel solvent resembles a more commonly known liquid called aqua regia. Known for being very corrosive, aqua regia consists of a mixture of nitric acid and hydrochloric acid that, in the correct ratio, can dissolve nonreactive elements such as gold and platinum.

      Although it can be used to extract gold, there are several disadvantages to using aqua regia. First, the components of the solution react with one another, speeding up the decomposition of the liquid and reducing its effectiveness. Furthermore, only one kilogram of gold can be extracted with 5,000 liters of aqua regia, none of which can be recycled.

      As a result, the solution developed by Foley is currently considered one of the best options for commercial extraction of gold from electronic wastes.

      • Re: (Score:2)

        by EvilSS ( 557649 )
        Just googled and yes, it's this research being used: https://news.usask.ca/articles... [usask.ca]

        A start-up company formed by University of Saskatchewan (U of S) researcher Stephen Foley, with two of his former students and a business partner, struck gold Thursday night on CBC’s Dragons’ Den. The panel on the reality TV show offered to chip in a total $1 million for a stake in the venture, Excir Works.

      • Once upon a time, I bought a car and decided to take a long drive in pursuit of an impressive cumulonimbus. This eventually brought me to a region that was nearly surreal: cyanide leach heaps at a gold mine, complete with skull and crossbones signs, and creepy sprinkler systems. I am glad if a better way has been discovered.

    • The plastics and light elements burn away then whatever is left just dissolve it in stong acid and you'll have the gold left over.

    • Re: (Score:2)

      by lazarus ( 2879 )

      Indeed. Excir's web site is just a big business card and doesn't say how it is done. However, this sort of amalgamation is typically done with Mercury which is a big red flag.

    • Re: (Score:2)

      by necro81 ( 917438 )
      Their technique uses an acetic acid solution, developed at University of Saskachewan. (The main researcher, Stephen Foley, is a professor of chemistry there, and now is the board director of this new company Excir.)

      phys.org [phys.org]
      youtube [youtube.com]

      The technique selectively dissolves the gold, which for PCBs is typically plated over nickel, which itself is typically plated over the outermost copper layers. Presumably, other techniques would be needed to remove the nickel. The copper (which is the majority of the m

      • Re: (Score:2)

        by EvilSS ( 557649 )
        I imagine they could run it through a heating process and remove the solder and components. I imagine it wouldn't be too hard to make machines to automate that. Or maybe there is a chemical process that can remove it in a step before it's run through to remove the gold.

    • Re: (Score:2)

      by e3m4n ( 947977 )
      hydroflouric acid. It desolves most mestals, but not nickel, gold, platinum, or silver. It also disolves glass and most plastics. So essentially you can pan that gold right back out of your soup you just made.

    • Re:How? (Score:4, Interesting)

      by h4x0t ( 1245872 ) on Wednesday October 20, 2021 @11:39AM (#61910187) Homepage
      The correct answer is cyanide leaching followed by carbon loading/ unloading and electrowinning. Just like the mines do. It's the most economic/ selective process for good extraction.

    • Do it the old fashioned way with mercury. Boil off the mercury and you're left with gold. Do this outdoors and stay upwind though...

  • Are they still gonna ship them (Score:3)

    by rsilvergun ( 571051 ) on Wednesday October 20, 2021 @10:25AM (#61909947)
    to 3rd world countries where they can use dangerous chemicals without worrying about worker safety and/or groundwater? Because that's how these schemes have traditionally been profitable. If you have to recycle electronics safely and cleanly it's a huge money sink. Places that want to do it have to put taxes on the devices to cover the cost and have local governments closely oversee everything. If they turn their backs for a moment the companies involved are dumping toxic sludge into the water supply (or the air, as burning is sometimes used).

    • Re: (Score:2, Informative)

      by Shane A Leslie ( 923938 )
      It's a company in Alberta form what I can find; so they will just pour their waste into old oil wells, open pit mines, or nearby rivers that flow through indigenous land.

      • Re: (Score:1)

        by Anonymous Coward
        I'm not seeing a downside here...

  • the greenest thing is to not use chemicals at all. and leave the gold where it is.

    • the greenest thing is to not use chemicals at all. and leave the gold where it is.

      Your title is absolutely true, but your point has a lot of asterisk's *(ZERO clue how to spell or punctuate that):

      Continuing to generate more products the same way isn't green which means doing nothing has a cost
      Investigating ways to separate any of the parts/chemicals in a low-impact way is time and money well spent

      The best solution in my rosey-glassed world would be to find replacements/alternatives for connecting material (solider, adhesives) that can be 'released' under specific industrial setting

      • I think worrying about what to do with 100 grams of plastic and ignoring the 20 milligrams of gold is pretty sound advice.

        • I think worrying about what to do with 100 grams of plastic and ignoring the 20 milligrams of gold is pretty sound advice.

          Exactly. On a long enough timeline, certain types of waste build up until someone sees a big payday due to free materials and innovation starts. We just got to keep it stored safely long enough (preferably having some company like Tesla or Apple secretly warehousing tons of it for later use).

          But you're right, it's like 'recycling' mechanical keyboards for their springs and chucking everything else . . .

          • If the gold can pay for the safe disposal or otherwise unprofitable recycling of the other stuff, that's good though.

            • Sadly economics is not the only dimension and being environmentally responsible is more complicated than an accounting register. The reagents you use to extract gold have an environmental risk and energy cost to them that aren't reflected in a businesses bottom line, especially for wealthy nations that seem to subsidize nearly every industry.

  • Where? (Score:4, Informative)

    by necro81 ( 917438 ) on Wednesday October 20, 2021 @11:01AM (#61910063) Journal

    The plans would see precious metals recovered at room temperature at the mint's site in Llantrisant, in Rhondda Cynon Taf, instead of electronic waste leaving UK shores to be processed at high temperatures in smelters.

    From the overabundance of consonants, that'd be in Wales somewhere?

    Ah yes, wikipedia provides [wikipedia.org]. That is the location where the UK Mint produces all its coinage.

  • Apple and others have been doing this for years. This is far from a first.
  • Some manufactures have also used aluminum or copper wiring in the past in place of solid gold wiring to cut material costs. https://www.thelvbags.co/louis... [thelvbags.co]

Slashdot Top Deals

Without life, Biology itself would be impossible.

Close