AW: [ RadSafe ] Article on Wired on Thorium reactors

[George Stanford]

Maury:
         Thanks very much -- it's a very interesting and useful paper,
and I'm pleased to have it.  However, a rather cursory scan through
it does not reveal any reference to chemical separation of Pa-233.
Is it there and I missed it?
         Best regards,
                 George
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At 12:19 AM 7/8/2005, Maury Siskel wrote:
Hi George,
Is this the paper you seek?

<http://home.earthlink.net/~bhoglund/multiMissionMSR.html>http://home.earthlink.net/~bhoglund/multiMissionMSR.html

Cheers,
Maury&Dog  <mailto:maurysis at ev1.net>maurysis at ev1.net

=======================
George Stanford wrote:

(1)  FRANZ:  You say

      "the uranium supply is limited first of all by the cost
      of mining. Even the use of weapons uranium and
      downblending will give only a few years or decades
      of postponement of serious problems. . . . At this
      time of history the use of breeder technology seems
      to be politically impossible to choose."

         Let's all hope that that political attitude will soon change.
The current thermal reactors extract less than one percent
of the energy in the mined uranium.  MOX recycle cannot
improve that efficiency by more than 15% or so.

         Fast reactors, however can extract the other 99%, or
close to it.  Back in 1983, B. L. Cohen showed that, with fast
breeders, uranium can supply the world's energy until the sun
engulfs the earth -- in other words, uranium is just as inexhaustible as
the other "renewables"  -- and it's much more available for bulk use.
Given that efficiency, the cost of mining is virtually irrelevant; even
extracting uranium from seawater becomes economically practical.

Reference: B.L. Cohen, Breeder reactors: A renewable energy
source, American Journal of Physics, vol. 51, (1), Jan. 1983.
I have a PDF version, available on request.

(2)  RADSAFERS:  U-233 is indeed a splendid material for bombs,
provided it is not contaminated with U-232, which is extremely
radioactive.  In a thorium reactor, Th-232 becomes Pa-233, which
decays to U-233 with a 27-day half-life.  Thus it is possible in
principle to get isotopically pure U-233 by chemical separation of
Pa-233 before it decays.  I seem to recall that a practical method
of doing that has been devised, but I can't find the reference.
REQUEST : Does anyone out there know of such a paper?

         Thanks.

                 George Stanford
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