IMPROVEMENTS IN THE MANUFACTURE OF SODIUM
Year: 1884

page_text: I, SIDNEY GILCHRIST THOMAS of 9 Palace Chambera, Westminster Bridge,
London but temporarily residing at El Biar in the French Colony of Algeria
Metallurgist, do hereby declare the nature of my invention for IMPROVEMENTS IN
THE MANUFACTURE OF SODIUM to be as follows:-
The reduction of Sodium from Carbonate of Soda is at present effected by
heating the latter with Carbon in small wrought iron retorts heated externally.
These retorts are very rapidly destroyed and their renewal is very costly-Instead
of these externally heated retorts, I place the mixture of Carbonate of Soda and
carbon in a retort or tube which may be of wrought or cast iron and is lined with
a thick lining of magnesia or lime or fritted dolomite or other refractory material
unacted upon by sodium such as carbon or graphite. Instead of firing these retorts
externally I heat the mixture by passing into the interior of the tube reducing
gases as free as possible from Oxygen and Carbonic acid; these gases having been
first heated to a very high temperature by passing through regenerative stoves
which have been intensely heated by burning in them producer or other gases. In
this way the reduction of the sodium is more completely effected and the cost of
the retorts very greatly reduced. The operation may be rendered almost continuous
by constantly introducing fresh quantities of sodic carbonate and carbon into the
retort by means of a closed hopper.
The reducing gases which may consist chiefly of Hydrogen or carbonic oxide are
subjected, after passing through the retorts, to rapid cooling by passing through an
artificially cooled condensing chamber which may be cooled by the circulation of
water in pipes or otherwise and the sodium-vapor which is carried over is here
condensed.
The gases must be either forced through the retorts by a pressure blower or by
an exhaust.

page_text: I SIDNEY GILCHRIST THOMAS of 9 Palace Chambers Westminster Bridge
London, but temporarily residing at El Biar in the French Colony of Algeria
Metallurgist do hereby declare the nature of my Invention for IMPROVEMENTS
IN THE MANUFACTURE OF SODIUM and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
The reduction of Sodium from Carbonate of soda is at present effected by heating
the latter with carbon in small wrought iron retorts heated externally, These
retorts are very rapidly destroyed and their renewal is very costly while the heating
of the mixture is inefficient. Instead of these externally heated retorts I place the
mixture of carbonate of soda and carbon in a retort or tube which may be of
wrought or even cast iron and is lined with a thick lining of highly fired magnesin
or lime or fritted dolomite or other refractory material unacted upon by Sodium
such as carbon or graphite. Instead of firing these retorts externally I heat the
mixture-by-passing-into-the-interior of the tube reducing gases free or as free as
possible from Oxygen and Carbonic acid, I prefer to uso water gas prepared from
Coke, these gases having been first heated to a very high temperature by passing
through regenerative stoves preferably of firebrick such as those of Siemens or
Cowper, but on a small scale, which have been intensely heated by burning in
then water gas or other gases. A sufficient number and area of regenerative
chambers is provided to enable a steady temperature to be maintained by their
alternate use. In this way the reduction of the sodium is more completely effected
and the cost of the retorts very greatly reduced. The operation may be rendered
alinost continuous by constantly introducing fresh quantities of sodic carbonate
and carbon into the retort by means of a closed hopper. The tubes or retorts are
of course of much larger diameter than those now cmployed. The reducing gases
which will consist chiefly of Hydrogen or Carbonic oxide are subjected after passing
through the retorts to rapid cooling by passing through an artificially cooled
condensing chamber which may be cooled by the circulation of water in pipes or
otherwise and the sodium-vapor which is carried over is here condensed. The gases
must be either forced through the retorts by pressure or by an exhaust. Potassium
may obviously be manufactured in a similar way. I do not claim the heating of
gases by passing them through heated regenerative chambers.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is
The improvement in the manufacture of sodium consisting in heating the
mixture of sodium salt and carbon by immediate contact with highly heated
reducing or neutral gases in a retort lined with a refractory material unacted on
by sodium.
Dated this eighth day of January 1885.