AN IMPROVED COMBINATION IN THE MODES OF TREATMENT OF OZOKERIT, BY MEANS OF WHICH THE YIELD IN PARAFFIN OR IN CERESINE IS CONSIDERABLY INCREASED
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by Albert Sauvée at the Office of the
Commissioners of Patents on the 24th October 1876. A communication from
abroad by Charles Cogniet, of Paris, in the Republic of France.
ALBERT SAUVÉE, of 22, Parliament Street, Westminster, London. "AN IMPROVED
COMBINATION IN THE MODES OF TREATMENT OF OZOKERIT, BY MEANS OF WHICH
THE YIELD IN PARAFFIN OR IN CERESINE IS CONSIDERABLY INCREASED."
Crude ozokerit is always more or less mixed with sand, earth, and water. To
remove these it is melted down in pans heated by steam pipes; the impurities fall
to the bottom of the pan and the ozokerit in a liquid state is decanted and
ready for distillation. The apparatus best adapted for this purpose is a large
balloon shaped vessel fitted with superheaters, such as is used for the distillation of
tallow; it is well known, and therefore needs no description.
I will now proceed with my improved mode of treatment of purified ozokerit.
It is introduced in the large balloon shaped still, resting on a furnace; the fire is
lighted and the temperature gradually raised to from 530° to 566° Fart.; steam at
this same temperature is then introduced inside the still, and the distillation im-
mediately begins. It is kept up by a moderate fire in the furnace, but the
temperature of the steam is raised till there is only a residuum in the vessel of
from 12 to 15% of the weight of the ozokerit,
During the distillation care must be taken to carefully separate the products into
two groups.
The first group will be a mixture of liquid hydrocarbons and of paraffin in a well
defined state of crystallisation; the second group will contain ozokerit, but slightly
decomposed; the first group will represent from 56 to 60%, and the second
from 25 to 30% of the ozokerit submitted to distillation. These figures can be
modified at will as you require a smaller or larger quantity of crystallised paraffin
or of distilled ozokerit slightly decomposed.
°
The quicker the distillation will have been carried on the larger will be the pro-
portion of the mixture of hydrocarbons and paraffin in the first group of products.
If on the contrary you let the fire down under the apparatus and only heat by
superheated steam, and the temperature of this superheated steam is only very
slowly raised, the decomposition of ozokerit will be limited, and the per-centage of
products in the second group considerably increased. The distillation may therefore
be controlled with the greatest ease.

page_text: The product in the second group, consisting of slightly decomposed ozokerit, can be
converted either into paraffin or ceresine, but it must be treated in a different way
in each case.
I will describe now the process to obtain paraffin, and later on the process to
obtain ceresine.
On account of its amorphous state the second group of products cannot be con-
verted into paraffin without having first been treated by sulphuric acid and sub-
mitted to a second distillation. The mass is therefore introduced into a double
bottom pan fitted with an agitator and the temperature is then raised to 245°
and 5° in weight of sulphuric acid is strongly stirred up in it for about one hour;
the mixture is then allowed to set, and the acid tar which is formed is decanted;
the same operation is repeated a second time with another quantity of 50% of sul-
phuric acid; after this the mass is well washed and it is ready for distillation again,
either by itself or with an addition of purified ozokerit.
The products resulting from the first group, as well as those from the recti-
fication of the second group, are melted together and cast into moulds of the same
dimensions as the trays of the presses, and when cooled you have flat cakes of oil
and crystallised paraffin; these cakes are hot pressed. This first pressure is in-
tended to free the paraffin of the largest quantity of empyreumatic oil and
impurities. The paraffin thus obtained is melted a second time and mixed with
from 15 to 20°/。 of its weight of oil resulting from the first pressing, but previously
refined, or with a same quantity of a similar liquid hydrocarbon. After cooling,
these second cakes are pressed, also the oil runs off, carrying with it impurities;
after this second pressing the paraffin is not sufficiently white; it must be submitted
to a third series of similar operations, with this exception, that the hydrocarbons
used must be sufficiently volatile to be easily carried off by steam.
After the third pressing the paraffin is sufficiently white, but it must be freed of
the smell imparted to it by some traces of the hydrocarbon which it still retains,
and this is obtained by passing dry steam freely through the mass till the smell
has completely disappeared. The paraffin so obtained from ozokerit is not then
absolutely white, even after filtering through animal charcoal in the usual way.
To obtain paraffin absolutely white the animal charcoal must be used when still
red hot from the calcining furnace, or it can be heated in a closed vessel; it is then
mixed in the proportion of 4 to 6% of the weight of paraffin; the mixture is
strongly stirred and then let to settle; after that it is filtered through unsized paper
or any other kind of appropriate filter. After this filtering the paraffin is cast into
moulds, is allowed to cool, and is then ready for the consumers. It is perfectly
white, diaphane, and without any odor. There ends the manufacture proper of
paraffin; but I now come to the special treatment of the secondary products resulting
from the various operations described above, and by means of which treatment
I obtain a new quantity of paraffin.
Treatment of Tar Oils resulting from the Distillation.-The tar oils left in the
still after the distillation of ozokerit are melted down either alone or still better
with an equal quantity of liquid tar resulting from the rectifying of the oils pro-
duced by the ozokerit, or of any similar product; the impurities fall to the bottom,
and the tar oils are decanted still hot and led into cast-iron retorts or to large vessels
heated by superheated steam. In the first case there is a decomposition of the tar
into liquid hydrocarbons and paraffin; in the second case the decomposition is much
less effectual, and the products obtained are in an amorphous mass, of a yellow tint,
rapidly getting brown by exposure to the air.
The products of the distillation in the retorts are set to cool and then filtered
either through bags or by means of a filter press. The paraffin resulting from this
filtering is added to that of the first group and treated with it; the amorphous
product of distillation in the large vessel is mixed to the second group to be treated
with it either for paraffin or ceresine, but as it is less purified it must previously to
its being used be purified by sulphuric acid.
Treatment of the Residuums of the several Pressings to which the Raw Paraffin

page_text: has been submitted. These residuums are melted to free them of the impurities
and of the water; after letting them set they are decanted and distilled in large
vessels heated by superheated steam; as the distillation goes on the products that
pass are divided into two groups, i.e.,-
1st group. Composed of essential oil.
2nd group. Composed of heavier oil and paraffin.
The essential oil and the heavier oil are used in the preparation of the various
mineral oils.
°
The products of the second group are not sufficiently compact to be hot pressed.
After being set to cool they are passed through a filter press and the cakes of paraffin
resulting are mixed with those obtained in the first group of products of the
distillation of raw ozokerit, and they go to increase the quantity of refined paraffin.
Treatment of Raw Cercsine formning the 2nd group of Products of the Distillation
of crude Ozokerit and of the Ceresine resulting from the rectifying of Tar Oils.-
The ceresine is first treated twice in succession by 5% sulphuric acid at 66° pre-
viously heated up to from 210° to 240°, and then a third time by 10% of the same
acid at the same temperature. After these three treatments the mass is hot pressed
and then mixed with from 5 to 6% of animal charcoal (red hot); the mixture must
be made inside a steam-jacketted vessel, being higher than broad; the charcoal is
then allowed a long time to settle, and the ceresine can be decanted and filtered;
but at equal temperatures the ceresine is much less fluid than paraffin, and the
filtering through unsized paper will be rather slow. It is therefore preferable to
filter it under pressure and by ascensum; this double action is obtained by fixing, at a
proper height above a steam jacketted filter, a pan in which the ceresine is kept in a
fluid state by steam; the pan and the filter communicate by means of a tube fixed
at their bottoms; in the filter, about 14 ins from the top, are fixed two diaphragms,
between which the filtering matter is deposited; the fluid ceresine runs from the
pan to the bottom of the filter, its level rises in the filter till it reaches the lower
diaphragm, it then passes through the filtering bed under pressure, and when it
reaches the top of the filter it overflows into suitable moulds. This operation
can be repeated according to the degree of whiteness of ceresine that you wish
to obtain.
Having thus described the nature of this Invention and the manner of performing
the same, I declare that what I claim as my Invention to be protected by the
herein-before in part recited Letters Patent:
1°. My improved mode of treatment by means of which I obtain from ozokerit a
larger per-centage and a superior quality of paraffin.
2°. The use of superheated steam as well as of the various modes of treatment
as herein described for the partial transformation of ozokerit into ceresine and for
obtaining purer and whiter ceresine.
3°. The use of animal charcoal at a very high temperature for obtaining whiter
paraffin and ceresine.
4°. The improved mode of filtering by ascensum and pressure for filtering
paraffin and ceresine.