IMPROVEMENTS IN SEPARATING SULPHUR PROM SODA WASTE
Year: 1866

page_text: LETTERS PATENT to George Tomlinson Bousfield, of Loughborough Park,
Brixton, in the County of Surrey, for the Invention of "IMPROVEMENTS
IN SEPARATING SULPHUR PROM SODA WASTE."-A communication from
abroad by Panajota Wilhelm Hofmann, residing at Dieuze, in the Empire
of France, Ph. D. Chemist.
Sealed the 15th March 1867, and dated the 8th October 1866.
PROVISIONAL SPECIFICATION left by the said George Tömlinson Bousfield
at the Office of the Commissioners of Patents, with his Petition, on the
8th October 1866.
I, GEORGE TOMLINSON BOUSFIELD, of Loughborough Park, Brixton, in the
County of Surrey, do hereby declare the nature of the said Invention for.
"IMPROVEMENTS IN SEPARATING SULPHUR FROM SODA WASTE," to be as follows:-
The soda waste taken from the lixiviating apparatus is spread on a floor in
a layer about 1 foot deep, and sprinkled over with a solution of chloride of
manganese or chloride of iron, or a mixture of the two; the quantity employed
may vary very much, but the most convenient proportion is for 100 lbs. of:
soda waste, 5-lbs. of the solution of 120 sp. gr. (water=100). The reaction
which takes place is the formation of sulphide of manganese or iron, both of:
which are by the contact of air soon transformed into free sulphur, and a
higher oxide of manganese or iron, which oxidizes-the sulphide of calcium,
[Price d

page_text: forming a body or several bodies, giving when lixiviated with water, on the
addition of an acid, a precipitate of sulphur without disengaging a sensible
amount of sulphuretted hydrogen. If now a fresh quantity of air is brought into
contact with the so-treated soda waste (and for this purpose it must be turned
over once or twice) the reduced oxide of manganese or iron is again oxidized,
and again reacts as before, and this goes on until the whole amount of sulphide
of calcium contained in the soda waste is oxidized; this transformation requires
several weeks, but for my purpose it is not necessary to get the mixture
completely oxidized, on the contrary, it is preferable to lixiviate the so-treated
soda waste after the lapse of 7 or 8 days; the water is most advantageously
employed at 50° centigrade, or hotter. When the lixiviation is carried out
properly a yellow ley is obtained of 110 sp. gr., yielding on the addition of
an acid free sulphur, which settles without difficulty to the bottom of the
vessel, and which may be melted either in a steam boiler under pressure or
in a solution of a salt which has no influence on the sulphur, and which can
be heated to at least 110° centigrade. The sulphur is melted in order to get
it purer and in a state more fit to be burnt. If the small amount of sul-
phuretted hydrogen disengaged by the treatment of the yellow ley by an acid
cases any inconvenience this operation may be executed in a close vessel,
the sulphuretted hydrogen evolved may be passed either into a solution of
perchloride of iron, when sulphur is precipitated, or it may be burnt in such a
way that water and sulphur is formed, or it may be transformed entirely into
water and sulphurous acid, which can be passed into another quantity of the
yellow ley in order to form hyposulphite of lime, or the sulphurous acid can
be used directly for the manufacture of sulphite and hyposulphite of soda and
sulphuric acid. The soda waste which has been left for years in contact with
air does not under these circumstances give the same amount of the yellow ley,
but it can be treated nevertheless most advantageously in the following
manner: Some holes several feet deep are made in the heap of soda waste,
into which during several days a large quantity of a solution of chloride of man-
ganese or of iron is poured; it soon filters into the soda waste, in this state the
mixture is left for a week or two to the contact of the air, and afterwards
lixiviated with water by pouring a large quantity of water into the same holes,
the yellow ley thus obtained is allowed to drain into a ditch at the bottom of the
heap. Instead of precipitating the yellow ley by an acid (hydrochloric acid),
it may be treated with an excess of an acid solution of chloride of manganese
so as to render the liquid acid; or it may be treated with an acid solution
of chloride of manganese until all the manganese is precipitated, thus a
mixture of sulphur and sulphide of manganese is obtained; or it may be

page_text: treated with an excess of a neutral solution of chloride of manganese when
sulphide of manganese is precipitated. The sulphide of manganese obtained
may be burnt to obtain sulphurous acid, and the manganese left be used again
for the manufacture of chlorine, or in case that it contains too little of binoxide
of manganese it may be heated in closed vessels with nitrate of soda, the
nitrous fumes given off being passed directly into sulphuric acid chambers, or
being condensed into nitric acid by means of water and air.
SPECIFICATION
in pursuance of the conditions of the Letters Patent, filed
by the said George Tomlinson Bousfield in the Great Seal Patent Office
on the 2nd April 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
TOMLINSON BOUSFIELD, of Loughborough Park, Brixton, in the County of
Surrey, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighth day of October, in the year of our Lord One
thousand eight hundred and sixty-six, in the thirtieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
George Tomlinson Bousfield, Her special licence that I, the said George
Tomlinson Bousfield, my executors, administrators, and assigns, or such others
as I, the said George Tomlinson Bousfield, 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 "IMPROVEMENTS IN SEPARATING SULPHUR FROM SODA WASTE," a
communication to him from abroad by the Inventor Panajota Wilhelm Hofmann,
a person resident at Dieuze, in the Empire of France, Ph. D. Chemist, upon
the condition (amongst others) that I, the said George Tomlinson Bousfield, 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 George Tomlinson Bousfield, do hereby._
declare the nature of the said Invention, and in what manner the same is

page_text: to be performed, to be particularly described and ascertained in and by the
following statement:―
The soda waste taken from the lixiviating apparatus is spread on the floor
and springled over and mixed with a solution of chloride of manganese, or
chloride of iron, or a mixture of both, which constitutes the liquid residue of
the preparation of chlorine. The quantity of solution employed can be varied
very much, yet I have found that 100 lbs. (one hundred pounds) of soda waste
and 5 lbs. (five pounds) of liquid residue of 12 specific gravity are a good
proportion. The reaction which takes place is the formation of sulphides of
manganese or of iron; for this reason the same effect would be produced in
mixing with the soda waste instead of solution of chloride of manganese and
iron newly precipitated sulphurets of manganese or of iron; both of these
sulphurets are by the contact of air soon transformed into free sulphur and
higher oxydes of manganese or iron; these oxydise the sulphide of calcium
and give rise to several compounds containing sulphur, calcium, and oxygen,
soluble in water, and whose solutions on the addition of an acid or an acid salt
give a precipitate of sulphur without disengaging a sensible amount of sul-
phuretted hydrogen. This transformation lasts several weeks; it goes on
quicker when the external temperature is high or when the soda waste is
several times turned over and well submitted to the action of the air. For our
purpose it is not necessary to get the soda waste completely oxydised; on the
contrary, it is more advantageous to lixiviate the prepared soda waste after
8-12 days (less in summer and more in winter time) with cold or hot water
in tanks methodically arranged. A yellow lye is obtained of about 110 specific
gravity, which on the addition of an acid liquor yields a large quantity of pul-
verulent sulphur settling without difficulty to the bottom. The liquor is
drained off, the sulphur can be pressed, or it can be melted in contact with a
weak alkaline solution (with weak yellow lye) in a closed boiler under pressure
so as to raise the temperature above 110 degrees centigrade. If the small
amount of sulphuretted hydrogen engaged by the treatment of the yellow lye
by an acid or by the liquid residue of chlorine preparation should cause any
trouble this treatment could be executed in a closed vessel and the sulphu-
retted hydrogen evolved either passed in a solution of perchloride of iron or
burnt in suitable burners in order to be transformed sometimes in sulphur and
water, according as the one or the other of these bodies may be most useful.
A very simple way and convenient apparatus for the evolution of sulphu-
retted hydrogen consists in a leaden conical vessel, the summit of the cone
being adapted to an iron or leaden pipe conducting the gas to the burner.
The yellow lye and the acid liquor are conducted separately by two lead pipes

page_text: to the bottom of the conical vessel; they meet there, neutralise each other,
disengage the sulphuretted hydrogen which rises to the top of the cone and
enters the abducting pipe, the neutralised liquor with the precipitated sulphur
flows out by one or two curved pipes bent downwards so as to prevent the
exit of any bubbles of gas. Instead of precipitating the yellow lye by an acid
it may also be treated, 2dly, by an excess of an acid solution of chloride of
manganese to render the liquid acid; in this case sulphur is precipitated;
3dly, by an acid solution of chloride of manganese until all the manganese is
precipitated a mixture of sulphide of manganese and sulphur is obtained;
4thly, by an excess of a neutral solution of chloride of manganese when
sulphide of manganese is precipitated. The sulphide of manganese obtained
in the process 3 and 4 may be burnt to obtain sulphurous acid, and the man-
ganese left may be used again for the manufacture of chlorine, or in case that
it contains too little of bi-oxyde of manganese it may be heated in closed
vessels with a certain amount of nitrate of soda, the nitrous fumes given off
may be passed directly into the sulphuric acid chambers or be condensed into
nitric acid by means of water and air. The residue constitutes a very pure
bi-oxyde of manganese mixed with sulphate of soda by lixiviation; the two
bodies are easily separated. A solution containing at the same time chloride
of iron and chloride of manganese being gradually mixed with a solution of sul-
phuret of calcium or with the yellow lye we have found out that all the iron
is first precipitated in the state of sulphuret of iron, so that a very pure solution
of chloride of manganese is easily obtained. This solution separated from the
precipitate of sulphuret of iron yields with the yellow lye a mixture of com-
pletely pure sulphuret of manganese and sulphur; this mixture being roasted
gives off sulphurous acid and a residue containing pure oxyde of manganese and
sulphate of manganese. This residue, as also the pure peroxyde of man-
ganese obtained by the calcination of the residue with nitrate of soda and
lixiviation, are used very advantageously in the fabrication of glass.
Having described as exactly as possible the nature of the said improvement,
and the manner of performing it, I claim as my Invention,-
1°, the peculiar treatment of soda waste in order to facilitate its oxydation
and the formation of soluble sulphurated calcium compounds.
20, the manner of obtaining with the prepared soda waste the most useful
yellow sulphurated liquors.
3°, the treatment of this yellow liquor with acids or solution of acid salts of
ron and manganese in order to obtain either sulphur or mixture of sulphur
and sulphides of iron and manganese,