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- From: whitbeck@equinox.unr.edu (Michael Whitbeck)
- Newsgroups: sci.chem
- Subject: Re: Gold - future Auto Catalyst
- Message-ID: <4863@equinox.unr.edu>
- Date: 18 Nov 92 02:18:16 GMT
- References: <1992Nov14.173858.2562@ucsu.Colorado.EDU> <1992Nov16.193403.16355@news.clarkson.edu> <1992Nov16.223502.27207@alchemy.chem.utoronto.ca>
- Organization: University of Nevada, Reno
- Lines: 80
-
- In article <1992Nov16.223502.27207@alchemy.chem.utoronto.ca> mroussel@alchemy.chem.utoronto.ca (Marc Roussel) writes:
- :In article <1992Nov16.193403.16355@news.clarkson.edu>
- :rajat@sunny3.che.clarkson.edu (Rajat Kapoor,P303,2124) writes:
- :>One of the unfortunate fallouts, IMHO, of the above reaction is that the
- :>Japanese plan to use Au as one of the active materials for catalytic
- :>convertors.
- :[...]
- :>Gold has a charm like no other metal.
- :>Putting this in ceramic monoliths would make it practically irrecoverable.
- :>
- :>By the same count, I don't like the idea of Gold being used as a
- :>filler material for teeth. Unless it is removed after death, that gold
- :>would be taken off "circulation".
- :>
- :>In either of the above cases the quantity is substantial if numbers
- :>are taken into account.
- :>
- :>Next on the list : Gold as conductor for IC's.
- :
- : At least in this last application, the gold is recoverable. In
- :fact, there are companies in operation today whose sole purpose is to
- :recover gold from circuit boards. I will certainly agree that, due to
- :human superstition, it's not likely we'll be recovering gold from
- :graveyards anytime soon. However, you shouldn't underestimate our
-
- oh yeah? this is a well established profession dating back at
- least to the days of the pharohs!
-
- :ability to get around difficult extractive problems when necessary: If
- :ever we needed it again, we would find a way to get it out of catalytic
- :converters.
-
- I'd almost bet that it would be easier to get the gold out of
- the converters than from an IC chip --- those cross-linked
- polymers are stuborn. How many posts show up starting with
- "is there a solvent for the plastic encapsulation of an IC?"
-
- The catalysis is, I believe, from Au METAL on exposed surfaces-
- make sure the Au is reduced (a little hot H2 or CO) then leach
- in aqueous NaCN....The hard part (expensive part?) is in
- separating similar metals. Like Au and Pd or Rh....(should I
- mention that Au use in electronics is mainly as an alloy with
- another 'noble' metal (Pd or Rh) as a hardener? and that it is
- difficult to economically separate the metals from the spent
- plating solutions? or that said solutions get dumped, legally
- and otherwise?.....Naaaaah, better not).
-
- : These observations are however not the reason I am posting. I would
- :like to know if anyone else thinks that Rajat's posting is silly. (I
-
- of course it is ... but so are most of the postings on any given
- day
-
- :tried to find a more tactful term, but I couldn't.) First of all, I
- :haven't heard that there is anything even remotely resembling a gold
- :supply crisis. Secondly, gold makes pretty jewelry, but so what? I
-
- You are right gold, is not really all that rare.
- Pt may be more rare; it is used in converters and in jewelery
- too. So the more Au used for converters the more beautiful Pt
- for jewelery... about time too!
-
- I read somewhere (Basin and Range?) that only 10% of the Au in
- the Sierra Nevadas (all of Nevada?) has been recovered -- beats
- me how any one arrives at such a figure.
- [Although I one saw a report, late '60s, that said we would run
- out of oil by the '80s and nearly did too!]
-
- :would rather have it play a useful technological role than see it wind
- :up as a useless ornament. Am I the only one with this sort of opinion?
-
- Well, I agree. But let the marketplace prevail! I rather like
- having a watch band that doesn't rust :-)
-
- :
- : Marc R. Roussel
- : mroussel@alchemy.chem.utoronto.ca
-
-
- Mike
-