Improvements in and connected with the Recovery of Zinc from Galvanised Iron and Steel.
Year: 1890

page_text: Date of Application, 21st Jan., 1890
Complete Specification Left, 25th Oct., 1890-Accepted, 29th Nov.. 1890
PROVISIONAL SPECIFICATION.
Improvements in and connected with the Recovery of Zinc from
Galvanised Iron and Steel.
I, HARRY GRIMSHAW, of the Canal Chemical Works Clayton Manchester in the
County of Lancaster, Chemical Manufacturer, do hereby declare the nature of this
invention to be as follows:-
This invention relates to the recovery of zinc from galvanised iron and steel and it
has for its object to recover the zinc without materially acting upon or injuring the
iron or steel. It has further for its object to enable the process of recovery to be
carried out either in the galvanising works or elsewhere without the erection of special
plant except of the simplest description.
According to these improvements I dissolve the zinc from the surface of the iron
or steel by means of a solution of the chloride, of the nitrite, or of the sulphate of
zine, or of a mixture of these solutions by the aid of heat and with or without the
addition of sulphuric, hydrochloric or nitric acid.
In
The process may be originated by employing a dilute solution of hydrochloric, nitric,
or sulphuric acid, when the acid of the bath will combine with the zinc to form the
salt in solution; or, the salt may be dissolved in water to form the bath.
either case in continuing the process, fresh portions of acid and fresh quantities of the
galvanised metal are added from time to time as may be required and the saturated
liquor may be drawn off, and the cleansed metal be removed as they respectively
accumulate so that the process may be continuous. If the head developed by the
reaction is insufficient to maintain the bath at a temperature of about 200 deg. F.
artificial heat may be applied.
Dated this 19th day of January A D 1890.
WILLIAM E. HEYS,
Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in and connected with the Recovery of Zinc from
Galvanised Iron and Steel.
I, HARRY GRIMSHAW of the Canal Chemical Works Clayton, Manchester 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 recovery of zinc from galvanised iron and steel and it
has for its object to recover the zinc without materially acting upon or injuring the
iron or steel. It has further for its object to enable the process of recovery to be
carried out either in the galvanising works or elsewhere without the erection of
special plant except of such as is of the simplest description.
According to these improvements 1 dissolve the zinc from the surface of the iron
by means of a solution of the chloride, of the nitrate, or of the sulphate of zinc, or of
a mixture of these solutions, and by the aid of heat.
There may be added to the solution hydrochloric, nitric, or sulphuric acid for the
production of the chloride, nitrate ar sulphate by the combination of the acid with the
zinc, the removal of the zinc from the iron being sought to be effected by its solution
in the solution of the salt of zinc assisted only by the presence of a small amount of
acid, an excess of acid being prejudicial both to the iron or steel and to the resulting
solution of the zinc salt.

page_text: The process may be originated by employing a dilute solution of one of the acids
hereinbefore named, when the acid of the solution will act upon the zinc and com-
bining with it will form the salt in solution; or, the zinc salt may be dissolved in
water to form the bath, or the bath may be otherwise separately prepared. In either
case, in continuing the process, fresh portions of acid and fresh quantities of the
galvanised metal are added from time to time as may be required, and the saturated
liquor and the cleansed metal may be removed as they respectively accumulate so that
the process may be continuous.
If the heat developed by the re-action is insufficient to maintain the bath at a
temperature of about 200 degrees F. artificial heat should be applied to bring the
bath to about that temperature.
The zinc salts contained in the solution may be separated therefrom by any of the
known means.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is―
The hereinbefore described process for the recovery of zinc from galvanised iron
and steel, which process consists in dissolving the zinc in a hot solution of the
chloride sulphate or nitrate of zinc either neutral or acidulated with hydrochloric
sulphuric or nitric acids, substantially as set forth.
Dated this 22nd day of October A.D. 1890.
WILLIAM E. HEYS,
Agent for the Applicant.