Year: 1898

page_text: this invention to be as follows:-
I first take dolomite (magnesium limestone) (either raw or calcined) and decom-
pose with hydrochloric acid (HCI), thus forming a solution of the two chlorides of
calcium and magnesium. I then proceed by boiling preferably in an open vessel
with steam and slaked lime or slaked dolomite (paste) until the whole of the
mixture or composition is decomposed into calcium chloride (solution) and mag-
nesium hydrate in suspension or as a precipitate
CaCl,+MgCl2 + CaHo₂ = 2 CaC₁₂+MgHo₂.
The magnesium hydrate is separated by filtration and remains on the filter the
liquid calcium chloride passing through.
If necessary or convenient I take a
solution of magnesium chloride already made and treat in like manner with calcium
hydrate (or slaked dolomite) and obtain like results.
Having obtained magnesium hydrate in this manner I find it is possessed of
peculiar and valuable active properties and I now introduce it into an iron still
together with a solution of sulphate of ammonia which when (agitated and) heated
(with steam or fire) decomposes, thus forming ammonia which distils over and
passes through condensers and collected in the usual way. The liquid which
remains in the still consists of a solution of magnesium sulphate which I (purify
if necessary and) crystallize as Epsom salts.
The calcium chloride solution previously obtained can be utilized as follows or
in any other way:-I mix with it a solution of zinc chloride and treat the mixed
chloride with a solution of sulphate of ammonia thus forming a precipitate of
calcium sulphate and a double chloride of zinc and ammonia.
I separate the
The double
precipitate by filtration and purify, wash etcetera ready for sale.
chloride (after purification) I now evaporate and crystallize for sale. Or I take
calcium chloride previously mentioned and treat with a solution of sulphate of
ammonia thus forming calcium sulphate and ammonia chloride which is previously
stated. I separate by filtration and prepare the calcium sulphate for sale (as
usual) and evaporate and crystallize the ammonia chloride for sale.
Dated this 25th day of June 1898.
WM. P. THOMPSON & Co.,
6, Bank Street, Manchester, Patent Agents.

page_text: Improvements in the Manufacture of Ammonia and Ammonium
Chloride and certain Bye-products.
I, THOMAS CRYER, trading as Deanhead Chemical Company, Littleborough, in
the County of Lancaster, Chemical Manufacturer, do hereby declare the nature of
this invention, and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
This invention relates to the manufacture of ammonia and ammonium chloride,
and, as intermediate and bye-products, of magnesium hydrate, magnesium sul-
phate, calcium sulphate, and calcium chloride.
In proceeding according to my present invention, I decompose normal or
calcined dolomite (magnesian limestone), with hydrochloric acid. The product is
a solution of the chlorides of calcium and magnesium. This solution is heated
in suitable vessels with a paste of slaked lime or of slaked magnesian lime or of
a mixture of them. The result of this treatment is that the lime is substituted
for the magnesium in the original solution, and that the magnesium is separated
as insoluble magnesium hydrate. Thus:-
-
CaCl2 + MgCl2 + Ca(OH), = 2 CaCl₂ + Mg(OH)2.
Instead of treating a solution of the mixed chlorides of calcium and magnesium,
I may, when local conditions permit, treat a solution of magnesium chloride with
the paste of slaked lime under heat. The product in this case is the same.
In either case, the magnesium hydrate is separated by the usual means such as
filtration or sedimentation and decantation.
It will be understood that the proportion of hydrate of lime added to the
solution of mixed chlorides is that indicated by the equation herein before given.
The separated magnesium hydrate, which possesses peculiarly active properties,
is then introduced into an iron still with an equimolecular mixture of ammonium
sulphate, where the mixture is agitated and heated. Free ammonia distils over
and may be condensed and collected by the usual known means.
There remains in the still, a solution of magnesium sulphate which is run off,
purified if necessary, and evaporated so as to crystallise out the magnesium
sulphate (Epsom salts.)
The solution of calcium chloride left after the separation of the magnesium
hydrate as hereinbefore described, may also be treated with a solution of ammonium
sulphate containing an equimolecular proportion. The products of this reaction
are ammonium chloride in solution and a precipitate of calcium sulphate. These
are separated by filtration or otherwise as is well understood, and the calcium
sulphate may be dried for sale, and the ammonium chloride solution evaporated
for the crystallisation of the chloride.
Instead of treating the calcium chloride solution alone with ammonium sulphate
as last herein before described, I may previously mix with it any convenient pro-
portion of another suitable chloride such as zinc chloride. The products of the
subsequent treatment with ammonium sulphate are calcium sulphate, and a mixed
chloride instead of the single chloride of ammonium.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is: : _
1. The manufacture or production of ammonium chloride by treating a solution
of or containing magnesium chloride with slaked lime, separating the resulting

page_text: magnesium hydrate from the calcium chloride solution, mixing the solution with
a solution of ammonium sulphate, separating the precipitated calcium sulphate
and evaporating the resulting solution of ammonium chloride, substantially as
described.
2. The manufacture or production of ammonia by treating a solution of or con-
taining magnesium chloride with slaked lime, separating the precipitated mag-
nesium hydrate and mixing it with a solution of ammonium sulphate and finally
distilling off condensing and collecting the ammonia, substantially as herein before
described.
3. The manufacture or production of Epsom salts as a bye-product in the
manufacture of ammonia, by treating a solution of or containing magnesium
chloride with slaked lime, separating the precipitated magnesium hydrate and
mixing it with a solution of ammonium sulphate, distilling off the ammonia, and
evaporating the remaining solution, substantially as described.
W. E. HEYS & SON,
Agents for the Applicant.