A NEW OR IMPROVED PROCESS FOR THE MANUFACTURE OF GLAUBER'S-SALT FREE FROM IRON
Year: 1883

page_text: LETTERS PATENT to Herbert John Haddan, of Kensington, Middlesex, for an
•
Invention of A NEW OR IMPROVED PROCESS FOR THE MANUFACTURE OF
GLAUBER'S-SALT FREE FROM IRON communicated to him from abroad by
Doctor. B. Schmaltz, and C. A. Loewig, persons resident at Schoenebeck, on
the Elbe, in the German Empire.
PROVISIONAL SPECIFICATION left by the said Herbert John Haddan at the
Office of the Commissioners of Patents on the 20th January 1883.
"
HERBERT JOHN HADDAN, of Kensington, Middlesex, "A NEW OR IMPROVED
PROCESS FOR THE MANUFACTURE OF GLAUBER'S-SALT FREE FROM IRON a coin-
munication to me from abroad by Doctor. B. Schmaltz and C. A. Loewig, persons
resident at Schoenebeck on the Elbe, in the German Empire,
This invention has for its object to produce sodic sulphate, commonly called
Glauber's salt, free from iron.
For this purpose I dissolve common salt in a hot solution of kieserit of about
20 degrees Beaumé, and add to the resulting solution a liquid obtained by pouring
concentrated hydro-chloric acid over a certain quantity of ordinary Glauber's salt,
and filter the product over (ground) rock-salt in order to obtain by crystallisation
Glauber's salt free from iron.
The kieserit employed in this process, may either be that which occurs in
nature, or artificial kieserit obtained in the manufacture of potassic chloride or in
other ways.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Herbert John Haddan in the Great Seal Patent Office on the
20th July 1883.
HERBERT JOHN HADDAN, of Kensington, Middlesex "A NEW OR IMPROVED
PROCESS FOR THE MANUFACTURE OF GLAUBER'S-SALT FREE FROM IRON," a com-
munication to me from abroad by Doctor B. Schmaltz and C. A. Loowig, persons
resident at Schoenebeck on the Elbe, in the German Empire
With the usual process for producing sodic-sulphate, commonly called Glauber's-
salt, this substance cannot be obtained entirely free from iron which greatly injures
its quality and makes it unfit for many purposes. This invention relates to an
easy and cheap process enabling one to produce sodic sulphate perfectly free from
iron. This process consists chiefly of the following two operations.
. I, Concentrated muriatic acid is poured over crystals of ordinary sodic sulphate,
a certain quantity of the latter is thereby dissolved and an equivalent quantity of
sodic chloride formed. During this process the liquid will show a decrease of
temperature of 24° Centigrade. The said liquid is then decanted and used for the
second operation..
II Natural or artificial kieserit, the latter as obtained as a residue in the
manufacture of potassic chloride, or in other ways, is dissolved in water. A pure
solution of 20° Beaumé thus obtained is heated, and in this liquid a corresponding
quantity of dry ground rock salt is dissolved. Then the liquid obtained in the
first operation is added and the whole compound filtered through a layer of ground
rock salt.
This filtered product is left to cool slowly and stand for three days, whereby a
portion of the sodic sulphate forms crystals entirely free from iron. The crude
Glauber's salt thus obtained in the shape of crystals is relieved of the accompanying
water in the usual way.
By heating and partly evaporating the remaining lye, the Glauber's salt left in
it is obtained as a product containing little water, but mixed with sodic chloride
and is therefore used for saturating the kiescrit solution.
The heating of the lye is continued only as long as the latter yields. crystals
of Glauber's salt, during which period it retains approximately the same
concentration.
As soon as the concentration increases, the lye may be considered as exhausted of
Glauber's salt and the operation finished.
During the cooling of the lye, bitter-salt is morcover crystallized and may also
serve to strengthen the kicserit solution.
"
During the continued manufacture these proportions become more and more
favorable, so that the crystallized Glauber's salt represents approximately the whole
produce, and the lye which remains to be concentrated by evaporation is reduced to
a minimum.

page_text: concentrated bydrochloric acid over ordinary Glauber's salt, and subsequently
filtering the whole through rock salt, for the purpose of obtaining a pure product
by means of crystallisation, substantially as described.
In witness whereof I the said Herbert John Haddan have hereunto set my
5 hand and seal this 20th day of July A.D. 1883.
TT
TUTATDAN
Gal