New scam in the making?

[kazamir]

I read this on Google news which for the most part has good credentials.
http://www.thehindu.com/sci-tech/science/scientists-find-simple-method-to-extract-gold-from-old-phones/article9056485.ece

 

[anachronism]

There's really nowhere near enough information to make any judgement calls but I would say that the University of Edinburgh isn't known for developing scams.

It could be as simple as dissolving the product and using a resin strip formula to take out the PMs. They seem to be trying to develop a process that doesn't involve a furnace on a commercial scale but they would have to look long and hard about the waste levels and the treatment of it in order to compete.

Again the information is purposely vague but personally I don't think it's a scam in any way. It's research.

 

[Topher_osAUrus]

Sounds like they are dissolving everything, then using bdg to remove the auric chloride.

"Printed circuit boards are first placed in a mild acid, which dissolves all of their metal parts. An oily liquid containing the chemical compound is then added, which extracts gold selectively from the complex mixture of other metals."

Edit to add quote

 

[g_axelsson]

Another scientist that thinks the state of the art of refining is by dunking everything in a vat full of acid and that all gold is visible. If scientists get it this wrong, how could we ever blame a newbie to think that AR the lot and then just get the gold out is the way to do it.

I often wonder if the lack of knowledge is with the scientist or the reporter that has to relay the information and somewhere it is dumbed down to suite the recipient.

Göran

 

[rickbb]

I didn't think mild acid would dissolve gold without a strong oxidizer.

Putting a complete CB in mild acid would dissolve the tin solder and not the copper. At least that's what happens when I do it, which is for the purpose of dissolving the tin solder before I put it in AP to dissolve the copper.

Perhaps that is what they are "inventing" a new one step process and then adding something to suck up the foils to eliminate filtering the foils. :?:

 

[nickvc]

Like many scientific studies they ignore the basics and just look for a way to make things happen, it may well work but in the commercial world it probably will never happen, there may well be parts that can be adapted to commercial use or for the home refiner but the whole process wil never be used by the trade unless it can compete with present processes.

 

[Lou]

We need a face palm emoticon.

 

[patnor1011]

There you go.

 

[g_axelsson]

We need a face palm emoticon.

:thumbsup: :lol:

Göran

 

[Eamonn]

This gives some info on the chemistry. No idea if it stacks up.
http://phys.org/news/2016-08-recovery-gold-secondary-resources-simple.html

 

[Topher_osAUrus]

This gives some info on the chemistry. No idea if it stacks up.
http://phys.org/news/2016-08-recovery-gold-secondary-resources-simple.html

They are still using acids.

"To extract the gold species from the hydrochloric acid leaching solution, they added the primary amide to an aromatic hydrocarbon solvent. This extraction proceeded far more efficiently than the extraction with commercial reagents..."

Seems like a new bdg or something of the like.
Its kind of funny that they say:
"Addressing the issue that the chemistry of solvent extraction of gold is still poorly understood"

If they are still dissolving everything in AR,-or whatever concoction with HCl, whats wrong with traditional methods.. Seems like they are over complicating it.

I wonder if they've read Hoke.. :shock:

 

[g_axelsson]

This gives some info on the chemistry. No idea if it stacks up.
http://phys.org/news/2016-08-recovery-gold-secondary-resources-simple.html

The full article can be found at http://sci-hub.ac/, use "DOI: 10.1002/anie.201606113"

Abstract :

Waste electrical and electronic equipment (WEEE)
such as mobile phones contains a plethora of metals of which
gold is by far the most valuable. Herein a simple primary amide
is described that achieves the selective separation of gold from
a mixture of metals typically found in mobile phones by
extraction into toluene from an aqueous HCl solution; unlike
current processes, reverse phase transfer is achieved simply
using water. Phase transfer occurs by dynamic assembly of
protonated and neutral amides with (AuCl4)^- ions through
hydrogen bonding in the organic phase, as shown by EXAFS,
mass spectrometry measurements, and computational calculations,
and supported by distribution coefficient analysis. The
fundamental chemical understanding gained herein should be
integral to the development of metal-recovery processes, in
particular through the use of dynamic assembly processes to
build complexity from simplicity.

I have to apologize to the authors, they seem more knowing of current refining practices than the impression the popular articles gives.

The recovery of metals using solvent extraction can offer
significant environmental advantages over energy- and capital-
intensive pyrometallurgical routes, especially if a single
metal is targeted.[7] Selectivity of extraction is achieved by
designing a reagent that favors the phase transfer of one metal
from a mixed-metal aqueous leach solution to an organic
phase.[8] Currently, 25% of global Cu recovery is carried out
by hydrometallurgy using phenolic oxime reagents,[8] the
development of which relied on an understanding of the
coordination and supramolecular chemistry of copper.
In contrast, the chemistry that underpins the recovery of
gold by solvent extraction is poorly understood. Commercial
reagents such as MIBK (isobutyl methyl ketone), DBC
(diethylene glycol butyl ether), and 2-EH (2-ethylhexanol)
recover gold as its metalate (AuCl4)^- from aqueous HCl by
solvent extraction (Eq. (1)), but exhibit selectivity, safety, and
mass-balance issues.[9] Recent work has shown that dilute HCl
acts as a lixiviant for the metals in printed-circuit boards,[6d]
but due to a lack of selectivity the commercial reagents are
likely to recover significant quantities of unwanted materials.

This is not a finished procedure, it is a step on the way to understand liquid-liquid extraction in dept.

Göran