From: knapp@spot.Colorado.EDU (David Knapp)
Subject: Re: Gold - future Auto Catalyst
Organization: University of Colorado, Boulder
Date: Tue, 17 Nov 1992 15:20:54 GMT

In article <1992Nov17.045858.20410@cs.rochester.edu> dietz@cs.rochester.edu (Paul Dietz) writes:
>In article <1992Nov17.011919.14080@ucsu.Colorado.EDU> knapp@spot.Colorado.EDU (David Knapp) writes:
>
>> It isn't difficult to get the gold out of the converter, it is hard to 
>> collect all those converters from dumps, junk yards, ditches and
>> quarries from around the world that is so hard. It is simply not profitable
>> to run around digging converters out of the junk yard to extract a couple
>> milligrams of gold from it.
>
>On the contrary:  convertors are already being collected, to recover
>platinum group elements.


And palladium, no doubt. Can you email me with a reference so I can find the
extent and efficiency of the recovery?  While I know that some are recovered,
I had *not* heard that it was enough to make note of, and if they are being
recycled to a significant degree, I should know that. Where would I go in
my city to recycle my catalytic converter?


> > resources come from Alcoa.  The world does *not* have an infinite supply 
> > of *any* metal that is able to be gotten by man. Think about it, while 
> > there is certainly a *lot* of metal out there, *very* little of it is 
> > accesible to use because it is either too deep or too dispersed. The amount
> > of energy that goes into refining metals is *phenomenal*.
>
>There are metals that are widely dispersed.

Yes, that's what I said. And the ones that are *too* dispersed, are, by 
definition, too disperesed to make recovery cost effective.

>There are metals on which we expend large amounts of energy
>to refine.

Yes, that's what I said.

>These two classes are largely disjoint!

Which is irrelevant. They are both the largest factors in determining 
availability of the metal.

>*Almost all* the metal we use is aluminum or iron.  Almost all the
>energy expended on refining metals is on these two elements.  

Again, I agree, but which metals use most energy has nothing to do with
what I said.


>There
>are effectively infinite supplies of both metals at concentrations
      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

>only a few times less than current ores.  


Can you expound on what you mean by "effectively infinite"? I mean, is it 
infinite or isn't it?  Can something be 'effectively limited' and still be
unlimited? 

Correct me if I'm wrong, but the planet is finite, all the metals contained
are finite and some number. Since we cannot access anything but a tiny
fraction of the planet, the amount of anything we can get out of that is
then smaller. And since much of *that* contains only highly dispersed
(low concentrations) of the metal we wish to retrieve, we cannot cost
effectively mine all of *that*.  So we've just gone from finite to even 
smaller than finite and my original statment was simply that the supplies
which we can access and which are cost effective, are not infinite. If
that is not correct, again, please email me with references which refute that
so I can look into it.


>In dollar volume as well,
>most of the metal consumed is the low value stuff.  Even if the energy
>and dollar cost of the exotic elements like gold were to skyrocket,
>the total cost of metals would not increase by much.

But this has nothing to do with what I said. I did not address relative costs
of metals or even cost of *any* metal.

You've commented on mny things I didn't even mention so you might be 
thinking of a different post.



-- 
David Knapp                                      University of Colorado, Boulder
Perpetual Student                                   knapp@spot.colorado.edu
Newsgroups: sci.chem