IMPROVEMENTS IN THE PREPARATION AND IN THE USE OF POROUS SILICEOUS MATERIALS FOR FILTERING ACID AND OTHER LIQUIDS FILLING ACID CONDENSERS AND FOR SIMILAR PURPOSES
Year: 1882

page_text: LETTERS PATENT to Carl Friedrich Claus, of Mark Lane, in the City of
London, Chemist for an Invention of "IMPROVEMENTS IN THE PREPARATION
AND IN THE USE OF POROUS SILICEOUS MATERIALS FOR FILTERING ACID AND
OTHER LIQUIDS FILLING ACID CONDENSERS AND FOR SIMILAR PURPOSES."
"
PROVISIONAL SPECIFICATION left by the said Carl Friedrich Claus at the
Office of the Commissioners of Patents on the 28th August 1882.
CARL FRIEDRICH CLAUS, of Mark Lane, in the City of London, Chemist,
"IMPROVEMENTS IN THE PREPARATION AND IN THE USE OF POROUS SILICEOUS
MATERIALS FOR FILTERING ACID AND OTHER LIQUIDS, FILLING ACID CONDENSERS,
AND FOR SIMILAR PURPOSES
"
.
This invention relates to the preparation and use of siliceous materials for
various purposes and is carried into practice as follows:-
I use for the purposes herein enumerated the material known as Ganister and
Dinas rock prepared and treated in the same manner as is customary for the
manufacture of Ganister and Dinas bricks. For acids that are not very strong I
sometimes use, in fact, the Ganister brick. For filtering purposes, for instance,
I construct a false bottom of these bricks or slabs bound together by acid-resisting
cement such as sulphur and sand, or the like. For the filling of acid condensing
towers I break up the bricks into pieces of convenient size and fill the towers with
the same as is now done with coke or I mould the material of which the Ganister
and Dinas bricks are made and form the same into prisms, balls, or other shapes,
dry and burn the same as is now done with bricks, and fill the acid towers,
gaylussac apparatus, glovers towers, and the like, with the same.
The extraordinary spongy and porous character of this material makes it a most
efficient substance for condensing purposes. The said material is also applicable as
a porous material in the apparatus used for the manufacture of anhydrous sulphuric
acid either impregnated with platinum sponge or for another operation in the same

page_text: process without platinum sponge. Ganister is a native siliceous material, which is
chilled in water and ground; the ground material is mixed with a small quantity
of lime, and moulded into bricks, which are dried and burnt as in the ordinary
manufacture of bricks. The burning is conducted at a very bigh temperature by
which the lime is converted into an acid silicate of lime which is insoluble in most
acids.
When I desire to produce a spongy material which possesses to an increased
degree the property of resisting the action of acids I prefer to use, instead of lime,
as a binding material for the ground or crushed Ganister, soluble silica (dialised
silica), soluble silicates, or precipitated silicates of baryta, of strontia, lead, or of
zinc, or I use the fluosilicate of the above bases as binding materials, a mixture of
two or more bases being preferred.
Of these binding materials I add a small quantity (say from two to five per
cent) to the crushed Ganister, mould the mass into the required shape and dry, and
burn the same at white heat. I also manufacture a similar material to that
described above by substituting for the crushed Ganister, crushed flint or the
material called infusorial earth which is almost pure silica and is of an exceedingly
spongy nature, or I make mixtures of two or of all these materials. Instead of the
precipitated silicates I may also use very finely ground glass and silicate of soda, or
instead of the fluosilicates I may use finely ground fluor spar.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Carl Friedrich Claus in the Great Seal Patent Office on the
28th February 1883.
CARL FRIEDRICH CLAUS, of Mark Lane, in the City of London, Chemist,
"IMPROVEMENTS IN THE PREPARATION AND IN THE USE OF POROUS SILICEOUS
MATERIALS FOR FILTERING ACID AND OTHER LIQUIDS, FILLING ACID CONDENSERS,
AND FOR SIMILAR PURPOSES"
This Invention relates to the preparation and use of silicious materials for
various purposes, that is to say, I use for the purposes herein enumerated the
material known as Ganister or Dinas rock. Ganister is a native silicious material,
which for the purpose of manufacturing bricks therefrom is calcined and chilled in
water and ground; the ground material is mixed with a small quantity of lime
and moulded into bricks, which are dried and burnt as in the ordinary manufacture
of bricks. The burning is conducted at a very high temperature, by which the
lime is converted into an acid silicate of lime, which is insoluble in most acids.
According to my Invention this material is prepared and treated as in the
ordinary manufacture of Ganister and Dinas bricks. For acids that are not very
strong I sometimes use the Ganister bricks themselves, for filtering purposes, for
instance I construct a false bottom of these bricks or slabs bound together by acid-
resisting cement such as sulphur and sand or the like. For the filling of acid-
condensing towers I break up the bricks into pieces of convenient size and fill the
towers with the same instead of filling them with coke; or I mould the material of
which the Ganister and Dinas bricks are made and form the same into prisms, balls,
or other shapes dry and burn them as in the manufacture of bricks, and use them
for filling acid towers "Gay Lussac "apparatus "Glovers towers" and the like.
The extraordinary spongy and porous character of this material makes it a most
efficient substance for acid condensing purposes. It is also applicable as a porous
material in apparatus used for the manufacture of anhydrous sulphuric acid, that is
to say it may be used in such manufacture in one operation, impregnated with
platinum sponge, and in another operation without platinum sponge.
When I desire to produce a spongy material which shall possess to a very high
degree the property of resistance to the action of acids, I use, instead of lime as a
binding material for the crushed Ganister, a silicate of more than one base and I
find the silicates of lead, baryta, strontia, alumina, zinc and lime are very
advantageous for this purpose.
A combination of any two or more of these silicates may be employed and such
silicates may be formed or obtained in any convenient manner. They may be
formed for instance, by fusing silica together with the above named bases and
grinding the fused mass into fine powder, or they may be produced by mixing
solutions of silicate of soda or of potash with the bases or their carbonates or
sulphates.
The finer the state of division in which the silicates are used the smaller will be
the quantity required and the more porous and acid-proof will be the product.
I prefer for this reason the silicates obtained by precipitation from solutions of
their oxides by means of solutions of silicate of soda or of potash. Alumina may be
employed in the form of China-clay.
I take either of the above named bases or oxides or their carbonates, sulphates,
or silicates (but preferably a precipitated silicate) and mix the same with a solution
of silicate of soda or of potash to form a thin paste. This mixture is added to
Ganister (ground as for the manufacture of bricks) and forms, after fusion, the

page_text: binding material which holds together the particles of the Ganister. The pro-
portions vary according to the fineness of the grain of the crushed Ganister from
say two to five per cent in weight of the Ganister used.
Instead of proceeding as above specified it is practicable to mix the oxide of
lead, of zinc, of strontia, of baryta, or of lime, or the sulphates or carbonates
thereof, either alone or mixed with silicate of alumina, ground fluorspar, or the like
directly with the Ganister, but this method is not so advantageous as that herein-
before described.
These masses or mixtures of materials are moulded into the required shape viz,
into bricks, slabs, prisms, balls or the like, they are then air or kiln dried and
ultimately burnt in a heat equal to that of a porcelain kiln, at which heat the
silicates form with the silica of the Ganister, compounds containing a large per
centage of silica, and capable to a very high degree of resisting the action of acids.
I also manufacture a similar porous material to that above described by sub-
stituting for the whole or a portion of the crushed Ganister, crushed flint or the
substance called infusorial earth which is almost pure silica and is of an exceedingly
spongy nature, or I make mixtures of any or all of these materials.
Having thus fully described my said Invention and the manner of performing
the same, I wish it understood that I claim.
First. The manufacture of a spongy or porous acid-resisting material by
combining or mixing Ganister (or infusorial earth) with a silicate of more than one
base (either with or without alumina), substantially as set forth.
Second. The utilization in the construction of filters, acid towers, and similar
apparatus, of Ganister made spongy or porous, or other above named silicious
material rendered coherent, and worked into pieces or masses of suitable shape so
as to be capable of resisting acid, substantially as set forth.
In witness whereof I the said Carl Friedrich Claus have hereunto set my
hand and seal this Twenty seventh day of February in the year of our Lord
One thousand eight hundred and eighty three.
CARL FRIEDRICH CLAUS. (L.S.)