Year: 1886

page_text: I, WILLIAM ROBERT LAKE of the firm of Haseltine Lake & Co, Patent Agents,
Southampton Buildings in the County of Middlesex do hereby declare the nature
of my 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 is a process for the extraction of pure metallic aluminium from
its chloride, or from the double chloride of aluminium and sodium. The distinctive
feature is the fusing of the chloride or the double chloride with lead oxide, a flux,
and charcoal; followed by the reduction of the mass with metallic magnesium.
Aluminium and lead in metallic state are produced, and may be mechanically
separated in various ways, such as by pouring the fused material into water, when
the metals separate by gravity.
The process is carried into effect, as follows;-
To one pound of chloride of aluminium is added one half pound of lead oxide,
two pounds of chloride of sodium and one half pound of charcoal. These ingredients,
after being intimately mixed, are fused in a suitable crucible. The resulting
compound after cooling is powdered. To the powder obtained are added one
sixteenth of an ounce of metallic magnesium also in pulverized condition, and a
flux, such as muriate of potassium. The whole is re-fused in a crucible for about
half an hour, until the mass melts, the contents of the crucible during fusion being
well stirred.
After cooling, the crucible may be broken and the mass removed in that way;
or, the contents of the crucible may be poured out, and allowed to cool in any
suitable receptacle. After cooling, the mass is pulverized.
It is well known that aluminium will not unite with melted lead and hence the
metallic aluminium exists throughout the mass in the form of small globules,
which may be separated out in various ways. It is preferable, however, to add to
the comminuted material another flux of muriate of potash with a trace of nitrate
of potash and fuse again. After this fusion the aluminium forms in much larger
globules. To separate these globules, the fused compound may be poured into

page_text: water, when the lead present being heavier sinks to the bottom of the vessel, and
the aluminium is found above.
In lieu of beginning the process above described with chloride of aluminium, the
double chloride of aluminium and sodium may be substituted; but, in order to
make this richer in aluminium, it is better to add to one pound of the double
chloride, one half pound of aluminium chloride. The remaining steps of the process
are the same as already described.
Any of the lead oxides may be employed. In place of chloride of sodium which
acts as a flux, chloride of potassium may be substituted. The metallic magnesium
acts as a reducing agent. Its employment is not absolutely essential to the
production of metallic aluminium; but it is of much value in facilitating the
process and is therefore preferably used. In place of pure metallic magnesium, a
magnesium alloy containing a suitable proportion of that metal may be employed.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated to
me by my foreign correspondent I declare that what I claim is ;-
The process of extracting metallic aluminium, substantially as hereinbefore set
forth