Improvements in the Manufacture of Mediums for Igniting Gas by its Own Action.
Year: 1895

page_text: Date of Application, 15th Jan., 1895
Complete Specification Left, 21st May, 1895-Accepted, 22nd June, 1895
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Mediums for Igniting Gas by
its Own Action.
I, JOHN FREDERICK DUKE of 3 Union Square, Newington in the County of
London, Chemist, do hereby declare the nature of this invention to be as
follows:-
This invention has reference to mediums whereby ordinary coal gas (alone or
mixed with air) or other gas containing hydrogen can be ignited by its own
action.
It is well known that platinum black or spongy platinum will occlude a large
quantity of oxygen from the air and that if a stream of hydrogen be directed upon
the platinum the chemical combination of the two gases takes place with sufficient
energy to raise the temperature of the platinum. Attempts have already been
made to take advantage of this property of platinum by applying it to the automatic
ignition of lighting coal gas. In these attempts the gas issuing from an ordinary
burner has been caused to blow upon the platinum contained in a receptacle so as
to warm this platinum sufficiently to render incandescent a fine wire of platinum
carried from the platinum in the receptacle to a position where it comes into
contact with the gas as it issues from the burner. This wire on becoming
incandescent ignites the gas.
None of these attempts has proved a practical success.
I have found by experiment that metallic platinum in the very finely divided
form known as platinum black or platinum mohr is the only form of platinum that
will cause the combination of the coal gas with its occluded oxygen at the ordinary
temperature with sufficient energy to produce a red heat or heat sufficient to render
incandescent a length of platinum wire when a current of cold carburetted
hydrogen or ordinary illuminating gas plays upon it. I have also found that after
a time the particles or atoms of the platinum black coalesce because the heat
communicated to them by the flame and by their own act of occlusion, combined
with the free access of the oxygen in the air tend to decarbonize or fuse the
platinum black.
When the particles have more or less coalesced they are not in a finely enough
divided condition to bring about the combination of the coal gas with the oxygen
of the air, at the ordinary temperature, with sufficient rapidity to render the wire
incandescent when a stream of cold carburetted hydrogen is passed over or
along it.
Now this invention consists in the employment for the purpose of automatically
igniting gas in the manner above referred to, of a block of porous material in the
pores of which platinum black is contained so that the particles or atoms of
platinum black are effectually prevented from coalescing with each other. The
invention also comprises the method or process of getting particles or atoms of
platinum black into the pores of the block.
For the purpose of my invention 1 take a solution of a platinum salt that is
soluble in water and I immerse therein a block or piece of a suitable porous
material so that the block may absorb some of the solution. I find meerschaum
which has been rendered anhydrous by being heated to a white heat eminently
adapted for the purpose. I then subject the meerschaum or other material

page_text: containing the platinum salt in its pores to the action of a substance which by
causing a chemical reaction will convert, the platinum salt to the metallic state
without having any chemical action on the material of which the block is composed,
the metallic platinum remaining in the pores in so finely divided a form as to
constitute platinum black.
In carrying out my invention I preferably use a solution of bi-chloride of
platinum, and after the meerschaum has absorbed into its pores as much of it as it
can take up, I subject the meerschaum to the action of carburetted hydrogen,
without the presence of atmospheric air, the carburetted hydrogen being heated to
a sufficient temperature to cause its hydrogen to combine with the chlorine of the
platinum bi-chloride and form hydrochloric acid gas; the platinum is thus reduced
to the metallic state. The action of the carburetted hydrogen should be continued
until hydrochloric acid gas ceases to be evolved.
Dated this 15th day of January 1895.
J. C. MEWBURN & ELLIS,
55 and 56 Chancery Lane, London, Patent Agents.
Improvements in the Manufacture of Mediums for Igniting Gas by
its Own Action.
I, JOHN FREDERICK DUKE of 3 Union Square, Newington in the County of
London, Chemist do hereby declare the nature of the said invention and in what
manner the same is to be performed to be particularly described and ascertained
in and by the following statement :-
This invention has reference to mediums whereby ordinary coal gas (alone or
mixed with air) or other gas containing hydrogen, can be ignited by its own
action.
It is well known that platinum black or spongy platinum will occlude a large
quantity of oxygen from the air and that if a stream of hydrogen be directed upon
the platinum the chemical combination of the two gases takes place with sufficient
energy to raise the temperature of the platinum. Attempts have already been
made to take advantage of this property of platinum by applying it to the
automatic ignition of lighting coal gas. In these attempts the gas issuing from
an ordinary burner has been caused to blow upon the platinum contained in a
receptacle so as to warm this platinum sufficiently to render incandescent a fiue
wire of platinum carried from the platinum in the receptacle to a position where it
comes into contact with the gas as it issues from the burner. This wire on
becoming incandescent ignites the gas.
None of these attempts has proved a practical success.
I have found by experiment that metallic platinum in the very finely divided
form known as platinum black or platinum mohr is the only form of platinum that
will cause the combination of the coal gas with its occluded oxygen at the ordinary
temperature with sufficient energy to produce a red heat or heat sufficient to render
incandescent a length of platinum wire when a current of cold carburetted
hydrogen or ordinary illuminating gas plays upon it. I have also found that after
a time the particles or atoms of the platinum black coalesce, because the heat
communicated to them by the flame and by their own act of occlusion combined
with the free access of the oxygen in the air tend to decarbonize or fuse the
platinum black.
When the particles have more or less coalesced they are not in a finely enough
divided condition to bring about the combination of the coal gas with the oxygen
of the air, at the ordinary temperature, with sufficient rapidity to render the wire

page_text: incandescent when a stream of cold carburetted hydrogen is passed over or
along it.
Now this invention consists in the employment for the purpose of automatically
igniting gas in the manner above referred to, of a block of porous material in
the pores of which platinum black is contained so that the particles or atoms
of platinum black are effectually prevented from coalescing. The invention also
comprises the method or process of getting particles or atoms of platinum black
into the pores of the block.
For the purpose of my invention I take a solution of a platinum salt that is
soluble in water and I immerse therein a block or piece of a suitable porous
material so that the block may absorb some of the solution. I find meerschaum
eminently adapted for the purpose. I subject the meerschaum or other material
containing the platinum salt in its pores to the action of a substance which by
causing a chemical reaction will reduce the platinum salt to the metallic state
without having any chemical action on the material of which the block is com-
posed, the metallic platinum remaining in the pores in so finely divided a form
as to constitute platinum black.
In carrying out my invention I preferably use a solution of bi-chloride of
platinum, preferably of 5 cubic centimetres of water to one ounce of the platinum
bi-chloride, or a weaker solution may be used, with repeated immersions and
drying. After the meerschaum has absorbed into its pores as much of it as it
can take up 1 subject the meerschaum to the action of carburetted hydrogen,
taking care to exclude the atmospheric air, the carburetted hydrogen being heated
to a sufficient temperature (say about 150° Centigrade) to cause its hydrogen to
combine with the chlorine of the platinum bi-chloride and form hydrochloric
acid gas; the platinum is thus reduced within the pores of the meerschaum to
the metallic state known as platinum black or platinum mohr. The action of
the carburetted hydrogen should be continued until hydrochloric acid gas ceases
to be evolved.
The accompanying drawings show by way of exan.ple and on an enlarged scale
how a gas burner may be fitted with a porous block containing platinum black as
herein before described so that when the tap turned on the gas becomes ignited
by its own action in the manner set forth.
Figure 1 is an elevation of the burner and of the porous block and its holder
attached to the burner. Figure 2 is a similar view but with the block and its
holder in section, and Figure 3 is a plan.
a is the burner. b is the block of porous material. c is a tube attached to one
side of the burner a; the block rests upon the upper end of this tube and is
secured by the screw cap d, the tube c and cap d together constituting the block
holder. e is the platinum wire fixed at one end to the inside of the tube c; it
passes through the block b and its other end is carried above the burner to the
position seen in Figure 3, that is to say just where the gas and air mix. The
block 6 is shown as formed with external furrows; these are for the purpose of
offering more surface to the stream of gas. The shape of the block and the means
of holding it in position may obviously be considerably modified.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed declare that what I
claim is :-
1. A medium for igniting gas by its own action in the manner set forth,
consisting of a block of meerschaum or other suitable porous material in the pores
of which platinum black is contained as hereinbefore described.
2. The process or method hereinbefore described of manufacturing a medium for
igniting gas by its own action which process consists in causing meerschaum or
other suitable porous material to absorb a solution of bi-chloride of platinum or
other platinum salt and then subjecting the said material to the action of a
substance which will reduce the platinum salt to the metallic state within the

page_text: pores of the material in so finely divided a form as to constitute platinum black,
substantially as set forth.
Dated this 21st day of May 1895
J. C. MEWBURN & ELLIS,
55 and 56 Chancery Lane, London, Chartered Patent Agents.