IMPROVEMENTS IN THE MANUFACTURE OF CHLORINE
Year: 1846

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
WATSON PATTINSON, of Felling, in the County of Durham, Manufacturing
Chemist, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Scal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Fourteenth day of July,
One thousand eight hundred and forty-six, in the tenth year of Ier reign, did,
for Herself, Her heirs and successors, give and grant unto me, the said
William Watson Pattinson, my exois, adññors, and assigns, Her especial
licence, full power, sole privilege and authority, that I, the said William
Watson Pattinson, my exois, adûiors, and assigns, or such others as I, the
said William Watson Pattinson, my exors, adñiors, or assigns, should at any
time agree with, and no others, from time to time and at all times during
the term of years therein expressed, should and lawfully might make, use,
exercise, and vend, within England, Wales, and the Town of Berwick-upon-
Tweed, my Invention of "IMPROVEMENTS IN THE MANUFACTURE OF CHLORINE,"
in which said Letters Patent is contained a proviso, that I, the said William
Watson Pattinson, shall cause a particular description of the nature of my
said Invention, and in what manner the same is to be performed, by an
instrument in waiting under my hand and seal, to be inrolled in Her said
Majesty's High Court of Chancery within six calendar months next and
immediately after the late of thes said in part recited Letters Patent, as in

page_text: and by the same, reference being thereunto had, will more fully and at large
appear
NOW KNOW YE, that in compliance with the said proviso, I, the said
William Watson Pattinson, do hereby declare that the naturo of my said
Invention, and in what manner the same is to be performed, are fully described
and ascertained in and by the following description thereof, reference being had
to the Diawings her cunto annexed, and to the figures and letters marked
thereon (that is to say)
-
My Invention consists in a method of expelling from a mixture of munatic
acid and oxide of manganese a larger quantity of chlorme than that hitherto
usually obtained from the same by makers of chlorine and bleachung powder;
which method is attended with other advantages.
The manufacture of chlorine, as hitherto practised by me and other manu-
facturers, has been to take muriatic acid of specific gravity 1160 or about 32°
of Twaddle's hydiometer, and cause it to act upon powdered black oxide of
manganese in a still or vessel formed of stone, and set in an non steam case,
so as to be heated by steam applied externally.
Figure 1 is a section of one of these stills or vessels without its ion steam
case. a, a, a, a, is the stone vessel; b. b, its cover, c, an opening in the covei
for introducing or withdrawing the materials, d, an earthen pipe through
wluch the chlorine is conveyed away; i, 2, 2, 15 a shelf or false bottom formed
of stones laid across the still, and supported by upught pieces of stone at the
height at from five to ten inches above the true bottom of the still a vessel.
Figure 2 is a plan of this still or vossel a, a, of stone, b, b, the cover; c, the lid;
the exit pipe for the chloine; c, g, openings in the cover, one for running
in muriatic acid, and the other for guaging to ascertain when the proper
quantity is introduced. And the mode of working formerly practised was to
lay upon the false bottom or sholt a quantity of oxide of manganese (ground
to powder), and then to add the proper quantity of muriatic acid of the requisite
strength; steam was then introduced into the oater iron case, and suffered to
net for the space of thirty-six to forty-eight hours, during which time the
contents of the still became heated, and much chlorine was evolved, the
temperature of the materials in the still or vessel seldom using higher than
180° Fahrenheit, by which process much less than the equivalent quantity of
chlorine (which the materials used ought to produce) was given off, occasioning
great, waste of valuable matter
Now, my improvement consists of the application to apparatus, such as above
described (or similar apparatus for the production of chloinc), of steam amoug
the materials in the still or vessel at a contain stage of the process, for which

page_text: purpose I apply a tube of stone, as shown in Plan at 3, Figure 2, and in Section
at h, h, Figure 1, where it will be observed that the jet of steam on entering is
duected along the bottom of the still under the shelf, and causes the liquor to
be agitated. My mode of proceeding is as follows.-I charge the still with.
muriatic acid and oxide of manganese, as heretofore, with the exception that
the latter is usod in lumps; I then apply steam externally in the steam casc,
as heretofore, until the contents of the still or vessel have 1cached the maximum-
temperature capable of being given to them by this means, and which (as
before stated,) is about 180° Fahrenheit), which may require about eighteen-
hours at this poiiod; much chlorine having been given off, I introduce steam.
through the tube, which rises directly among the residual materials in the still
oi vessel, the steam used by me being about ten pounds per inch, or higher,
by which the temperature of the materials is after some time rased to fiom.
212° to 220°, and nearly the whole of the remaining chlorine will be expelled..
I do not blow in the steam continuously after its first introduction, otherwise
the chlorine might be given off too rapidly, but I allow it to pass in at intervals.
of about half an hour, on and off, till the temperature above mentioned is
obtamed to the materials, which will generally be found to be during a period
of six hours, or until the whole charge has been in operation twenty four hours,
at which time the whole, or nearly the whole of the chlorine being expelled, I
remove the door c, and 1 un off the muriate of manganese preparatory to a ficsh
change. The advantage of this introduction of steam is not only to increase
the production of chlorine from the same weight of materials and to expedite
the process, but it renders unnecessary the grinding of the manganese, or the
agitation of the contents of the still or vessel by mechanical means, as
fiequently practised, for the steam itself produces a commotion within the still
or vessel that frees the manganese, placed in lumps upon the false bottom, of
auy sediment that may have formed upon it, and thus continually renews the
surface to be acted on by the acid. It is prope and important that I should
state that the steam should not be introduced into the still or vessel until the
temperature of its contents has reached 180°, or thei cabouts; for if it were
introduced at the beginning of the process, or before the contents of the still
have been sufficiently heated, too much of the steam might be condensed
within the still, and the strength of the muriatic acid reduced, so as to occasion
great loss and also danger from the generation of explosive combinations of
chlorine and oxygen; on these accounts, also, it is better to use ten pound or
higher pressure stoam within the still or vessel, by which the requisite tempera-
ture is obtained with the least condensation, as the chlorine evolved at this
high temperature is more liable to be mixed with steam than when it is given

page_text: off at a lower temperature. It is necessary when making bleaching powder to
dry the chlorine carefully by any of the usual methods before it reaches the
chambers; I employ for this purpose sulphuric acid, and for such purpose I
cause the gas to pass through a pipe containing coke, amongst which, from
time to time, sulphuric acid is allowed to flow.
I have thus described a still or vessel for the manufacture of chlorine fiom.
muriatic acid and oxide of manganese, and also the application of my Inven-
tion thereto, in order that the same may be clearly understood; but the
methods of constructing and heating stills or vessels for this purpose vary, most
manufacturers having some peculiar plan of their own for heating such vessels;
but each manufacturer may readily adopt my improvements with advantago.
What I claim as my Invention is the use of steam within a still or vessel
containing muriatic acid and oxide of manganese for the production of
chlorine, after the same shall have been heated up to a high temperature by
the application of heat externally, either by steam, as I have fully described,
or otherwise.
In witness whereof, I, the said William Watson Pattinson, have here-
unto set my hand and soal, this Eleventh day of January, in the year
of our Loid One thousand eight hundred and forty-seven.
WILLIAM WATSON (L.S.) PATTINSON.
AND BE IT REMEMBERED, that on the Eleventh day of January, in
the year of our Loid 1847, the aforesaid William Watson Pattinson camo
before our said Lady the Queen in Her Chancery, and acknowledged the
Specification aforesaid, and all and every thing therein contained and specified,
in form above written. And also the Specification aforesaid was stamped
according to the tenor of the Statute made for that purpose.
Eniolled the Fourteenth day of January, in the year of our Loid One
thousand eight hundred and forty-seven.