* User Info

Welcome, Guest. Please login or register.
Did you miss your activation email?

* Who's Online


Dot Guests: 90 | Dot Users
Dot Hidden: 0

* Board Stats

  • stats Total Members: 12650
  • stats Total Posts: 125205
  • stats Total Topics: 17430
  • stats Total Categories: 5
  • stats Total Boards: 48
  • stats Most Online: 814

* Advertisers

Author Topic: New way to recover gold. Using....CORNSTARCH!!!!  (Read 5503 times)

0 Members and 1 Guest are viewing this topic.

Offline cwalker

  • PPT Invited
  • *****
  • Posts: 39
  • Kudos: 0
New way to recover gold. Using....CORNSTARCH!!!!
« on: May 14, 2013, 05:24:57 PM »
Havent posted here in a while but I found this on some unrelated website and thought you lot would find it interesting.

Cornstarch Replaces Cyanide In Clean New Gold Extraction Method | Popular Science

3-4 links on the page that will take you to more of the "sciencey" type stuff.

Very interesting stuff!!!

EDIT: This, looks like some kind of lab video showing something......

Offline ebuyc

  • Weekend Prospector
  • PPT Invited
  • *****
  • Posts: 2016
  • Province/State: Spokane Valley, WA ; USA
  • Kudos: 53
  • 12 yrs of union-demolition, show me the bedrock!
    • My YouTube Channel
Re: New way to recover gold. Using....CORNSTARCH!!!!
« Reply #1 on: May 14, 2013, 05:31:36 PM »
Very cool - a buddy of mine repairs radios, computer, anything really and called me the other day asking if I wanted a shed full of motherboards from all kinds of things. I thought to myself "there are precious metals in that half a pick up load..." But told him to put the lot of Craigslist and have someone else come get it.

Now if I could leach the gold out chemically with a green enviro friendly process... very interesting indeed!

Did someone say       

Offline rexhavoc

  • Full Member
  • ****
  • Posts: 125
  • Kudos: 8
  • Somewhere in deepest, darkest Cariboo...
Re: New way to recover gold. Using....CORNSTARCH!!!!
« Reply #2 on: May 15, 2013, 11:45:31 AM »
Too bad that the chlorine compound (potassium tetrachloroaurate) did not work; as chlorine solutions are cheap and readily available; bulk bromine compounds may be more expensive to procure vs say bleach and hydrochloric acid. On the other hand, gold might have gotten a lot cheaper  :o

I'm also not clear on what practical (and environmentally friendly?) steps would be necessary to convert ore into potassium tetrabromoaurate before the cyclodextrin precipitation step - the author used nitric acid and hydrogen bromide gas - two distinctly difficult materials to work with (the former which will may you noticed by the authorities if accumulated in bulk).

But this breakthrough might cause quite a bang in the gold from scrap electronics biz where large quantities of relatively pure alloys are already at hand..?

Comments appreciated,

Offline coolshivers

  • PPT Invited
  • *****
  • Posts: 513
  • Kudos: 19
Re: New way to recover gold. Using....CORNSTARCH!!!!
« Reply #3 on: May 15, 2013, 12:09:49 PM »
until someone can put together a non lab version on GPEX that doens't take a rocket scienctist to implement. The cornstarch will stay in the pantry.

Offline overtheedge

  • PPT Invited
  • *****
  • Posts: 771
  • Kudos: 36
Re: New way to recover gold. Using....CORNSTARCH!!!!
« Reply #4 on: May 15, 2013, 05:17:23 PM »
Folks, read the headline and then think about the actual chemistry.
Then read the article and see ... bromine-gold salts.
The gold has already been leached out by a bromine compound, not all that much different from what NaCN does.
A bromine compound such as HBr  is not safer than NaCN. Both can cause bad things to happen to the body.

This article is typical of the low quality of reporters and editorial staff working for PopSci.
And this is the reason I let my sub lapse several decades ago.
Oo, did you read the comments? One bright lad was visualizing pumping the cornstarch over the leach heap.

Offline Geo Bill

  • Jr. Member
  • ***
  • Posts: 15
  • Kudos: 0
Re: New way to recover gold. Using....CORNSTARCH!!!!
« Reply #5 on: May 17, 2013, 02:20:23 PM »
  I read that article, seems a bit complicated for the home based gold leaching kit. I am aware of new nontoxic gold leach kits that use thiosulfate, bromine, chlorine, Iodine, and acids with catalysts. Ive heard that Iodine makes a stable compound with gold, albeit much more slowly than cyanide. I see these gold reclaiming kits on the web all the time, they're supposed to work, I also see nontoxic gold stripper for sale with plating chemicals in my jewelers catalogues. I would like to hear any feedback about what works and what doesnt. old 1970s circut boards have alot of gold on them, especially in the microchips, each little black plastic microchip has a tiny microprocessor inside soldered to a base with a droplet of gold, when you scan a large circut board there can be hundreds of these chips on them, not to mention the gold plated connector pins and "fingers" where it slides into the mother board. (or the motherboard for that matter), back in the early 90s I used to go dumpster diving and would find all kinds of electronic junk, I wasted most of it, sold the better stuff to some guys in california (like the ceramic chips). I salvaged some of the easier gold by electroplating the copper away from the pins and little copper foil fingers and  boiling the remainder in (the works) toilet bowl cleaner (it has an oxide remover called EDHA in it that removes the nickel underplating), after removing the nickel all thats left was stuff resembling shredded gold leaf which I melted by mixing it with borax on a piece of wood with a plumbers torch. a propane torch will melt gold just fine on a piece of wood with a pinch of borax (wet it so that the torch doesnt blow it all over) -- all in alll it was a total pain and probably not worth the time, a stripper that would just dissolve the gold would have been about a hundred times faster and gotten a much higher yield.