NetNews Usenet Archive 1992 #26/NN_1992_26.iso/spool/sci/misc/1799

Text File | 1992-11-09 | 1.9 KB | 39 lines

Newsgroups: sci.misc
Path: sparky!uunet!utcsri!helios.physics.utoronto.ca!alchemy.chem.utoronto.ca!mroussel
From: [e-mail] (Marc Roussel)
Subject: Re: Collection of Gasses
Message-ID: <[e-mail]>
Organization: Department of Chemistry, University of Toronto
References: <[e-mail]>
Date: Mon, 9 Nov 1992 17:44:15 GMT
Lines: 28

In article <[e-mail]> [e-mail]
writes:
>I have a question that has been bothering me for a while now.
>You can buy canisters the nobel gasses from supply houses.
>I am wondering how they find, isolate, and collect these
>gasses.

     I can give a partial answer to this question.  Most of the noble
gases (note the spelling) are collected as byproducts from various
mining processes.  Helium for instance is collected from natural gas
deposits.  (If the rocks are sufficiently impermeable to trap natural
gas, they are usually sufficiently impermeable to trap helium.  The
helium was just part of the initial mixture of gases which formed the
planet.  Any He in the atmosphere has escaped by now but some of it
became trapped during the solidification of the outer crust.)  Argon is
present in sufficient quantities in the crust (and is heavy enough not
to escape readily) that it tends to accumulate in people's basements;
I presume that the other noble gases can be found in similar ways.
     The purification process should be fairly simple.  One can first
use some set of chemical reactions to get rid of all the non-noble
gases.  (After all, we can fairly well count on the noble gases not
reacting except under unusually extreme conditions.)  Once that is done,
the noble gases should easily be separable from one another by gaseous
effusion since the mass ratios between successive members of the group
are reasonable.

                Marc R. Roussel
                                [e-mail]