IMPROVEMENTS IN PURIFYING PARAFFINE
Year: 1865

page_text: PROVISIONAL SPECIFICATION left by John Edgar Poynter at the Offico,
of the Commissioners of Patents, with his Petition, on the 12th June
1865.
I, JOHN EDGAR POYNTER, of Glasgow, in the County of Lanark, North
Britain, Manufacturing Chemist, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN PURIFYING PARAFFINE," to be as follows, that'
is to say:
This Invention consists in purifying paraffine by means of fusel oil, whereby
increased economy in the operation is obtained. Crude paraffine, or paraffine
in the state in which it is first obtained from among the products of the
distillation of coal shale or other source, is always associated with various
other hydrocarbons, which it is desirable to separate from it, and the object
of this Invention is to remove such hydrocarbon impurities.
In practising the Invention, according to one modification, about equal
weights of the crude or impure paraffine and of fusel oil (or hydrated oxide
of amyl, as the latter is termed by chemists,) are mixed together, and
sufficient heat is applied to liquefy the paraffine and facilitate thorough
intermixture. The heat should be as great as 130 degrees Fahrenheit, which
is about the melting point of paraffine, and it should not exceed 268 or 278
degrees Fahrenheit, which is about the boiling point of fusel oil, otherwise
the oil will be wasted by evaporation. The mixed paraffine and fusel oil are
allowed to cool, and the fusel oil is afterwards expressed or separated from
the paraffine by means of an oil press, when it will be found that a large

page_text: portion of the impurities of the crude or impure paraffine will have been
removed by the fusel oil. The process is repeated with fresh fusel oil until no
further impurities are removed thereby. If particular purity is required, or
it be desired to free the paraffine from the smell of fusel oil, any traces of
fusel oil remaining in the paraffine may be finally removed by applying heat
of a sufficient temperature to completely volatilize and drive off the fusel oil,
such temperature should not, however, exceed 300 degrees Fahrenheit, which
will be sufficient for driving off the fusel oil. The heat for the purpose may
be applied in various ways, as for example, by means of steam-jacketted
vessels. It may be sufficient for ordinary purposes to wash the purified
paraffine with hot water in order to remove the smell of the fusel oil.
By another modification a quantity of fusel oil sufficient without heat to
thoroughly dissolve the paraffine is used. The paraffine is then allowed to
crystallise, solidify, or deposit, which it does in a more or less purified con-
dition. The free fusel oil being drained off, or the paraffine being fished out
of the oil, any oil retained amongst the paraffine is expressed or separated by
means of an oil press. This process may be repeated as before until sufficient
purity is obtained, and in the final stage of purification the traces or smell of
fusel oil may be driven off by volatilising it, or by washing with hot water, as
before described. The fusel oil when charged with the impurities of the
crude paraffine is itself purified or renovated, so that it may be used over
again by distilling it in the ordinary way at the temperature necessary to
volatilise it, and by collecting it as it distils over in a cold receiver.