IMPROVEMENTS IN TREATING WASTE LIQUORS CONTAINING ARSENICAL OR PHOSPHATIC COMPOUNDS, AND IN OBTAINING AND APPLYING USEFUL PRODUCTS THEREFROM.
Year: 1872

page_text: LETTERS PATENT to James Higgin, of Manchester, in the County
of Lancaster, and John Stenhouse, of Pentonville, in the County
of Middlesex, for the Invention of "IMPROVEMENTS IN TREATING WASTE
LIQUORS CONTAINING ARSENICAL OR PHOSPHATIC COMPOUNDS, AND IN OBTAINING
AND APPLYING USEFUL PRODUCTS THEREFROM.
"
PROVISIONAL SPECIFICATION left by the said James Higgin and
John Stenhouse at the Office of the Commissioners of Patents, with
their Petition, on the 30th December 1872.
We, JAMES HIGGIN, of Manchester, in the County of Lancaster, and
JOHN STENHOUSE, of Pentonville, in the County of Middlesex, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN TREATING
WASTE LIQUORS CONTAINING ARSENICAL OR PHOSPHATIC COMPOUNDS, AND IN
OBTAINING AND APPLYING USEFUL PRODUCTS THEREFROM," to be as follows :-
Our Invention consists in recovering useful products from the waste
liquors resulting from the fixation of mordants upon textile fabrics and
yarns by solutions of salts of arsenic, arsenious, or phosphoric acids in
what is technically called the "dunging process," and in applying such

page_text: recovered products in the fixation of other mordanted fabrics and yarns.
We run the waste liquors into a vat or pit, and add thereto a solution
of muriate of lime or of other earthy or metallic salt which has the
property of forming an insoluble precipitate with the arseniates, arsenites,
or phosphates in solution in the waste "dunging" liquors. The
arseniates, arsenites, or phosphate of alumina or iron resulting from the
precipitation of the superfluous mordant detached from the fabrics or
yarns by the soluble arseniates, arsenites, or phosphates, and which are
in suspension in the waste "dunging" liquors, are precipitated at the
same time. We collect the resulting precipitate on a filter, and treat it
with a solution of a carbonate of an alkali, or with any other alkaline
salt which has the property of decomposing the precipitate, assisting the
action where necessary by heat, until the required double decomposition
has taken place, an alkaline arseniate, arsenite, or phosphate remaining
in solution, and the earthy or metallic base on bases previously combined
with the arsenic, arsenious, or phosphoric acids being separated in an
insuluble form. After separation by decantation or filtration of the
insoluble matter, we use the crude arseniato, arsenite, or phosphate of
alkali for the purpose of fixing or "dunging" mordanted textile fabrics
or yarns, neutralizing for some purposes with any suitable acid; or we
evaporate to dryness the liquid, or evaporate to such a point that
crystallization may take place, and we use the direct salt or crystals
dissolved in water for the purpose of fixing mordants upon textile fabrics
or yarns.
In some cases it is more convenient to collect the waste "dunging "
liquors in the same pit or vat in which the waste soap liquors are
collected, and precipitated by an earthy or metallic salt in the known
process of collecting such soap waste, and in that case the same agent
will precipitate both the fatty and arsenical or phosphatic matters. Wo
collect the mixed precipitates and dissolve out by a suitable acid the
arsenical or phosphatic salts, and after addition of lime or alkali to the
solution to precipitate the arsenical or phosphatic salts we treat the
precipitate as above described by double decomposition.
The remaining fatty matter can be treated according to the Specification
of Letters Patent granted to John Thom and John Stenhouse, dated
July the 22nd. A.D. 1872. No. 2186.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Higgin and John Stenhouse in the Great
Scal Patent Office on the 30th June 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, James
HIGGIN, of Manchester, in the County of Lancaster, and JOHN
STENHOUSE, of Pentonville, in the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirtieth day of December, in the year of our
Lord One thousand eight hundred and seventy-two, in the thirty-sixth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto us, the said James Higgin and John Stenhouse, Her special
license that we, the said James Higgin and John Stenhouse, our
executors, administrators, and assigns, or such others as we, the said
James Higgin and John Stenhouse, our 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 "IMPROVEMENTS IN TREATING WASTE
LIQUORS CONTAINING ARSENICAL OR PHOSPHATIC COMPOUNDS, AND IN OBTAINING AND
APPLYING USEFUL PRODUCTS THEREFROM," upon the condition (amongst others)
that we, the said James Higgin and John Stenhouse, by an instrument
in writing under our, or one of our 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 James Higgin on behalf of myself
and the said John Stenhouse, do hereby declare the nature of the said
Invention, and in what manner the same is to be performed, to be
particularly described in and by the following statement (that is to
say):-
Our Invention consists in a method of recovering useful products
from the waste liquors resulting from the fixation of mordants upon
textile fabrics and yarns by solutions of salts of arsenious, arsenic, or

page_text: phosphoric acid in what is technically called the "dunging process," and
in applying such recovered products in the fixation or "dunging" of
other mordanted fabrics or yarns. We run the liquor remaining in the
"dunging beck" after the operation of "dunging" has been performed,
and which is herein-after termed the "spent dunging bath,” into a vat or
pit and add thereto a solution of a salt of an alkaline earth, or of a salt|
of a metallic oxide which has the property of forming an insoluble
precipitate with the arsenites, arseinates, or phosphates in solution in
the spent "dunging bath." The arseintes, arseniates, or phosphates of
iron and alumina, or of both these bases resulting from the precipitation
by the arsenical or phosphatic salts of superfluous mordant detached
from the goods during the immersion in the "dunging bath," and which
are in suspension in the "spent dunging bath" are thrown down along
with the insoluble precipitato formed by the addition of the salt of
· alkaline earth or of metallic oxide, herein-after called the "precipitant.”
The precipitants we prefer are salts of lime, barytes, iron and
manganese, and generally cither as chlorides or sulphates. To ensure
the precipitation of the largest possible quantity of arsenical or
phosphatic compounds, we make the "spent dunging bath" alkaline
by means of alkali or soluble alkaline earth, preferring to use lime in
the state of cream or milk of lime added after the precipitant has been
mixed in. The precipitate thus obtained is allowed to settle, and the
supernatant liquor drawn off and run away. The precipitate, which
consists of the arsenical or phosphatic compounds of iron or alumina,
or of both formed in the "dunging bath," and the arsenical or phosphatic
compounds formed by the use of the precipitant, is transferred to a filter
preferably of woollen cloth, and drained to a stiff paste, a quantity of
which is then weighed and tested for the amount of bases contained in
it, and put in a pan or other vessel which can be heated either by steam
or fire. Where a salt of iron or of manganese has been used as the
precipitant, we now add a solution of mono-sulphide of sodium or
potassium in such quantity that there is one equivalent of such mono-
sulphide for every equivalent of iron, manganese, or alumina ascertained
to be present in the portion of paste under treatment, that is to say, we
add thirty-nine pounds of mono-sulphide of sodium, or fifty-five pounds
of monosulphide of potassium in solution in water for every thirty-six
pounds of protoxide of iron, or for every thirty-five and a half pounds of

page_text: protoxide of mangauesc, or for every. fifty-one and a half pounds of
alumina present in the paste sufficient water is now added to make the
mixture fluid enough for boiling, and it is now boiled for about two hours,
allowed to settle, and the supernatant liquor drawn off into another
vessel. The liquor now contains arsenite, arseniate, or phosphate of
soda or potash. Should it contain a little alkaline sulphido also, some
solution of hypochlorite of soda is added until the sulphide is oxidized
and rendered innocuous.
For the "dunging" of some styles of printed or dyed goods, tho
liquor can be used at once, for other styles it is too alkaline, and we then
ncutralize it with sulphuric, hydrochloric, or arsenic acid.
If a dry white salt is required, we evaporate the neutralized liquor to
dryness, adding some nitrate of soda when the liquor appears to contain
organic or vegetable matter, or when it contains arsenite of soda or
potash, a preliminary trial being made with a small quantity of the
liquor to ascertain the proportion of nitrate to be added. We then heat
the salt in a reverberatory or other furnace to a heat under redness until
sufficiently white. The salt thus produced can be used for all the
purposes for which the "dunging salts" of commerce are used.
The sulphide of iron or manganese, or of both resulting from the above
double decomposition is washed with water, and the washings reserved
for the next operations to be used in place of water. The sulphide
sediment may be transferred to a closed vessel, in the top of which thero
is a pipe. Dilute sulphuric or hydrochloric acid is now added, and
the sulphides are dissolved with evolution of sulphuretted hydrogen gas,
which is taken away by the pipe to some boiler or furnace ash-pit near
and allowed to mix with the air feeding the fire and thus become
destroyed.
In localities where the spent liquor of chlorine stills can be cheaply
obtained, the utilizing of the sulphide sediment need not be carried out,
as the mixed chlorides of iron and manganese in the still liquor will
answer perfectly well as a "precipitant." Where a salt of lime or
barytos has been used as a "precipitant," a portion of the paste is
weighed and tested for bases as before, put in a pan and an addition
made of carbonate of soda, potash, or ammonia in such quantity that
there is one equivalent of such carbonate for every equivalent of lime or
burytes present in the paste, and mono-sulphide of sodium or potassium

page_text: in solution in water in such quantity that there is one equivalent of
such mono-sulphide for each equivalent of protoxide of iron, and one
equivalent of mono-sulphide for cach equivalent of alumina present in
the paste, that is to say, that for every twenty-eight pounds of lime, or
for every seventy-six and a half pounds of barytes we take fifty-three
pounds of dry carbonates of soda, or sixty-nine pounds of dry carbonate
of potash, or thirty-nine pounds of dry carbonate of ammonia, and for
every thirty-six pounds of protoxide of iron we take thirty-nine pounds
of mono-sulphide of sodium or fifty-five pounds of the mono-sulphide
of potassium, and for every fifty-one and a half pounds of alumina we
take thirty-nine pounds of mono-sulphide of sodium, or fifty-five pounds
of mono-sulphide of potassium. Water sufficient to make a fluid
mixture is now added, and where carbonate of ammonia has been
added the mixture is kept at a heat of about one hundred degrees of
Fahrenheit's thermometer for three or four hours, stirring occasionally.
Where carbonate of soda or of potash has been used the mixture is
boiled for about two hours. The mixture is now allowed to settle and
the supernatant liquor drawn off, the sediment at the bottom, which is
mainly carbonate of lime with some alumina or sulphide of iron, or both,
.is washed with water, the washings drawn off and reserved for the next
operation to be used in place of water and the sediment thrown away.
The liquor may now be used in "dunging" some styles of mordanted
fabrics or yarns, but for other styles we neutralize with sulphuric,
hydrochloric, or arsenic acid.
Where carbonate of soda or of potash has been used to effect the
decomposition of the paste, the liquor can be converted into a dry white
salt as described, when treating of the liquor resulting from precipitation
by an iron or mangancse salt.
It is obvious that the quantity of arsenite, arseniate, or phosphate of
alkali present in the "spent dunging bath" will depend primarily on
the amount of such substances used during the process of dunging, and
secondarily, on the amount of arsenious, arsenic, or phosphoric acids
removed from the "dunging" bath by combining with the bases of the
mordants and being precipitated in or upon the fibre. The amount thus
removed will vary according to the more or less perfect decomposition of
the mordant by the fibre during what is technically known as the
"ageing" process, which also give rise to a variable quantity of mordants

page_text: detached from the goods during immersion in the "dunging" bath, and
consequently to a variable quantity of arsenite, arseniate, or phosphate
of the bases of the mordants being formed as insoluble precipitates in
the "dunging" bath. The amount of soluble arsenite, arseniate, or
phosphate remaining in the spent dunging bath, and which requires the
"precipitant" is thus a variable one, and no absolutely definite quantities
of "precipitants" can here be given, but generally we have found the
following method of proceeding and proportions of materials to be used
to give satisfactory results:-We form two pits in the ground made
water-tight in any convenient manner, each capable of holding the whole
of the "spent dunging baths," and each provided with an opening at onc
side which can be closed by a sliding board adjustable to any height.
Having run off a day's production of spent dunging bath" into one of
these pits, and having kept a record of the quantity of "dunging" salt
or "dunging" liquor consumed during the day, we add to the pit for
every ninty-nine pounds of arsenious acid, or for every one hundred and
fifteen pounds of arsenic acid, or for every seventy-one pounds of
phosphoric acid contained in the "dunging" liquor or salt used during
the day three hundred and ninety-three pounds of crystallized proto-
sulphate of iron, or a quantity of proto-chloride of iron containing an
cquivalent quantity of iron or a solution of sulphate or chloride of
manganese containing one hundred and six pounds and a half of
protoxide of manganese, or a quantity of chloride of calcium or sulphate
of lime, containing or being equal to eighty-four pounds of lime, or a
quantity of solution of chloride of barium, containing three hundred and
twelve pounds of dry chloride of barium, and a further addition of milk
or cream of lime until no further precipitation takes place on adding
clear lime water to a filtered portion of the liquor in the pit. The liquor
in the pit now is alkaline to test paper. It is allowed to settle all night,
and next morning the supernatant liquor is run off and the sediment
removed to a filter. The second pit is used for the second day's work,
and thus cach pit is worked alternately.'
Another part of our Invention consists in collecting the "spent
dunging baths" in the same pits in which the waste soap is collected,
as described in the Patent of Thom and Stenhouse, dated July 22nd,
AD 1872 No 2186 The snent dunoing bothe" and the

page_text: by means of alkaline, carbonates, and alkaline sulphides, either alone or
mixed.
And thirdly. The use of the solutions resulting from the above double
decompositions, or of dry salts made therefrom in the "dunging" or
fixing of mordanted textile fabrics or yarns.
In witness whereof, I, the said James Higgin, on behalf of myself
and the said John Stenhouse, have hereunto set my hand and
scal, this Twenty-eighth day of June, in the year of our Lord One
thousand eight hundred and seventy-three.
Witnessed by
GEORGE DAVIES, C.E.,
Patent Agent,
Manchester.
JAMES HIGGIN. (L.S.)