IMPROVEMENTS IN THE UTILIZATION CF WASTE PRODUCTS OF AMMONIACAL LIQUOR
Year: 1873

page_text: LETTERS PATENT to Arthur William Ellis, of Madeira Villas, Wood-
ford, in the County of Essex, Manufacturing Chemist, for the
Invention of "IMPROVEMENTS IN THE UTILIZATION CF WASTE PRODUCTS
OF AMMONIACAL LIQUOR."
Sealed the 20th June 1873, and dated the 8th April 1873.
PROVISIONAL SPECIFICATION left by the said Arthur William Ellis
at the Office of the Commissioners of Patents, with his Petition, on
the 8th April 1873.
I, ARTHUR WILLIAM ELLIS, of Madeira Villas, Woodford, in the
County of Essex, Manufacturing Chemist, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN THE UTILIZATION OF WASTE
PRODUCTS OF AMMONIACAL LIQUOR," to be as follows, that is to say :-
By the distillation of ammoniacal liquor, for instance in the manu-
facture of sulphate of ammonia, the volatile ammonia and other vapors
and gases are driven off; the remaining liquor is then treated with a

page_text: fixed alkali (for instance lime) by which the fixed ammonia is liberated,
and is then again submitted to the action of heat, and the remaining
ammonia thus driven off. The liquor which is thus (or in great part)
deprived of its ammonia has not hitherto been commercially utilized,
is herein-after called " the spent liquor.
"
According to my Invention I utilize the spent liquor as follows:-
I. In cases in which the spent liquor is neutral and contains sufficient
iron to combine with and precipitate the cyanogen substances I simply
allow the precipitate thus naturally formed to subside and then decant
the supernatant liquor. This precipitate usually of a grey color can
then be treated as herein-after described.
II. In cases in which the spent liquor is neutral but only contains
sufficient iron to convert the cyanogen substances into a ferrocyanide,
then I add an acidulated solution of a ferric or ferrous salt, which forms
a precipitate of a bluish green or grey color, but greatly varying.
III. In cases in which the spent liquor is neutral but does not con-
tain sufficient iron to convert the cyanogen substances into a ferro-
cyanide I add so much of a solution of sulphate of iron as will effect
that purpose with agitation, and then proceed in the manner secondly
herein-before described.
In cases in which the spent liquor shows an alkaline reaction I
neutralize the excess of alkali in the spent liquor with some suitable
acid.
The precipitates having been obtained in the cases herein-before
mentioned they may be digested or dissolved in a caustic alkali, such as
potash or soda, and the solution thus obtained filtered or decanted, and
neutralized, and again filtered or decanted and added to an acidulated
solution of a ferric or ferrous salt. The products thus obtained may be
treated in the methods ordinarily adopted in the manufacture of Prussian
blue. For instance if the precipitate is formed by the addition of a
ferric salt it will be of a rich blue color, if precipitated by a ferrous salt
it will be more or less of a grey or bluish grey color, in which case it
will be necessary to treat it with some suitable oxydizing agent.
The precipitates resulting as herein-before described can be separated
by any of the known methods, such as decantation, filtration, or a
combination of the two.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Arthur William Ellis in the Great Seal Patent
Office on the 4th October 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ARTHUR
WILLIAM ELLIS, of Madeira Villas, Woodford, in the County of Essex,
Manufacturing Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighth day of April, in the year of
our Lord One thousand eight hundred and seventy-three, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Arthur William Ellis, Her special
licence that I, the said Arthur William Ellis, my executors, adminis-
trators, and assigns, or such others as I, the said Arthur William Ellis,
my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for " IM-
PROVEMENTS IN THE UTILIZATION OF WASTE PRODUCTS OF AMMONIACAL LIQUOR,"
upon the condition (amongst others) that I, the said Arthur William
Ellis, my executors or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, should particularly describe
and ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Arthur William Ellis, 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 thereof, that is to say :—
By the distillation of ammoniacal liquor, for instance in the manu-
facture of sulphate of ammonia, the volatile ammonia and other vapors
and gases are driven off; the remaining liquor is then treated with a
fixed alkali, for instance lime, by which the fixed ammonia is liberated,
and the remaining liquor is then again submitted to the action of heat,

page_text: and the remaining ammonia thus driven off, or the lime may at once be
mixed with the ammoniacal liquor, in which case one operation only is
necessary to drive off both the free and fixed ammonia from the liquor.
The liquor which is thus (or in great part) deprived of its ammonia
has not hitherto been commercially utilized, and is herein-after called 5
"the spent liquor," and contains cyanogen.
According to my Invention I utilize" the spent liquor" as follows:-
In order to facilitate operations on large quantities I take a small
sample of "the spent liquor" to be operated on and ascertain whether
that liquor is neutral or alkaline; if alkaline I neutralize the excess of 1
alkali in the spent liquor with sulphuric acid, and then treat the spent
liquor thus neutralized in the manner herein-after set forth for neutral
liquor.
A. If the spent liquor is neutral and contains sufficient iron to
combine with and precipitate the cyanogen substances I simply allow 1
the precipitate thus naturally formed to subside. This precipitate is
generally of a grey color, but greatly varying.
B. If the spent liquor is neutral, but only contains sufficient iron to
convert the cyanogen substances into a ferrocyanide I add sufficient of
an acidulated solution of a ferric or ferrous salt to precipitate the 2
cyanogen substances.
This precipitate is of a bluish green or grey
color, but greatly varying.
C. If the spent liquor is neutral, but does not contain sufficient iron
to convert the cyanogen substances into a ferrocyanide I add to the
spent liquor with agitation so much of a solution of sulphate of iron as 2
will effect that purpose, and then proceed in the manner herein-before
described in case "B" as for a ferrocyanide.
In order to ensure the complete precipitation of the cyanogen
substances sought to be retained, it is necessary there should be a slight
excess of iron, and to ascertain whether this excess exists I proceed as 3
follows: I take a sample of the supernatant liquor under operation,
carefully filter it, and then add to it a solution of ferrocyanide of
potassium, which, if it produces in the event of a ferric salt being
used a blue precipitate or color, and in the event of a ferrous salt being
used a greyish precipitate or cloudiness, sufficient iron is present, and 3

page_text: the operation is finished; if, on the contrary, no precipitate takes place
I continue to add to the liquor under operation, of which the sample
was a part, a solution of a ferric or ferrous salt until a sample of the
filtered liquor produces with the above test the necessary reaction. As
a rough working guide, however, the presence of a brown or reddish
brown tint in the supernatant liquor is an indication of a sufficient
excess of iron. The presence of sufficient iron to convert the cyanogen
substances into a ferrocyanide can be ascertained by adding to the
sample of the liquor under operation a solution of a ferric salt, which if
a ferrocyanide is present produces a precipitate of a blue or bluish
grey color.
The precipitates having been obtained as described in the clauses
marked A, B, and C, or as described in A or B, or C and B, I allow to
subside, and then separate them from the supernatant liquor by de-
cantation, filtration, or a combination of the two, but by preference by
decantation. As the precipitate forms in very minute particles the filter
used must be very carefully constructed to prevent waste.
The vessels in which the liquors are to be mixed, and the precipitates
allowed to subside, should be made of wood and of as great a depth as
convenient, and supplied with an agitator. I obtain the precipitates in
the same vessels in which I add the reagent to the spent liquor.
The precipitates having been obtained as described in clauses A, B,
and C, are of great public utility, as by simple and well-known methods
many useful products largely used in the arts, such as ferrocyanide of
potassium, ferrocyanide of sodium, and Prussian blue can be developed
from them. For instance the precipitates can be dissolved in a caustic
alkali (potash or soda) and the solution thus obtained filtered or decanted,
then neutralized, and again filtered or decanted, an acidulated solution
of a ferric or ferrous salt is then to be added. The products thus
obtained, namely, ferrocyanide of potassium or sodium according to the
alkali used can then be treated in the methods ordinarily adopted in the
manufacture of Prussian blue. For instance if the precipitate is formed
by the addition of a ferric salt it will be of a rich blue color, if precipi-
tated by a ferrous salt it will be more or less of a grey or bluish grey
5 color, in which case it will be necessary to treat it with some suitable
oxydising agent such as ferric chloride or nitro-muriatic acid.

page_text: I precipitate the cyanogen substances in the spent liquor at a high
temperature, as I have found that by this means precipitation is facilitated,
but the precipitates may be obtained at the temperature of the
atmosphere. If the spent liquor is operated upon as before mentioned
in clauses A, B, and C, so soon as it leaves the distilling apparatus the
temperature is then sufficiently high.
2.
In order that the object of this Invention, and the method of carrying
it out may be the more fully understood, I give the following example
of how I treat the spent liquor when it possesses cyanogen substances in
the form of ferrocyanide, the one in which it is more likely to be found.
Suppose a vat, tank, or cistern of wood provided with an agitator, and
capable of holding, say, ten thousand five hundred gallons, and fitted
with a discharge cock for the supernatant liquor, and one for the pre-
cipitate, I introduce into this vat about fifty gallons of an acidulated
solution of ordinary commercial sulphate of iron, composed by weight
of one part of sulphate of iron to six of water; the agitator is then set
in motion, and, say, ten thousand gallons of the spent liquor is then
pumped or run into the vat. When the sulphate of iron and spent
liquor have been thoroughly mixed a sample is taken and tested in the
manner herein-before described to ascertain whether a sufficiency of iron
has been added. If sufficient has been added the agitator is stopped
and the mixture allowed to subside, the clear liquor is then run off and
the precipitate collected, and if required treated as herein described.
If, however, sufficient iron has not been added more is added until a
sample of the supernatant liquor taken (if necessary) from time to time
ceases to produce any further precipitate, and shews with the ferro-
cyanide test, as herein-before described, the necessary reaction, upon
which the whole mixture is allowed to subside, and the precipitate
collected as aforesaid. It must, however, be understood that as the
ammoniacal liquors vary considerably in the amount of cyanogen con-
tained the proportion of iron necessary to produce the best results can
only be determined by a preliminary experiment, and consequently the
above example is only given as a guide to the general working, as it is
possible that the proportion of iron therein mentioned may be in excess
of that required for some ammoniacal liquors.
Having thus described my Invention and the means I adopt in carry-

page_text: is, the utilization of waste products of ammoniacal liquor by the treat-
ment of the spent liquor, in the manner herein-before described in the
clauses hercof marked A, B, and C.
In witness whereof, I, the said Arthur William Ellis, have here-
unto set my hand and seal, this Fourth day of October, in the
year of our Lord One thousand eight hundred and seventy-three.
above-named Arthur William Ellis,
in the presence of,
JOHN GREENFIELD,
Clerk to Messrs. Bell & Crowder, Solrs.,
Victoria Buildings,
Queen Victoria St.,
London, E.C.
JOHN GREENFIELD,
Clerk to Messrs. Bell & Crowder, Solrs.,
Victoria Buildings,
Queen Victoria St.,
London, E.C.