Improved Coating or Preservative Material for Iron, Steel, and other Structures, or for Coating the Bottoms of Iron and Steel Ships or other Vessels, and Process of Manufacturing the same and other Products from Gas Tar.
Year: 1888

page_text: Date of Application, 13th July, 1888
Complete Specification Left, 13th Apr., 1889-Accepted, 15th June, 1889
PROVISIONAL SPECIFICATION.
Improved Coating or Preservative Material for Iron, Steel, and other
Structures, or for Coating the Bottoms of Iron and Steel Ships
or other Vessels, and Process of Manufacturing the same and
other Products from Gas Tar.
I, JOHN HUGHES EASTMAN, of 7, Newstead Road Liverpool, in the County of
Lancaster, Merchant, do hereby declare the nature of this invention to be as
follows:-
This invention has for its object, a preservative coating material for iron or steel,
that shall be capable of setting into a hard tenacious coat.
I use for this purpose gas
tar. This material, however, contains ingredients, such as ammonia and certain acids,
which as long as they remain in the tar, prevent it from forming such a coating. To
remove them therefore, 1 add, sulphate of lime, (plaster of Paris) and water.
These
are violently stirred up and intimately mixed with the tar. A double decomposition
occurs, the sulphuric acid combines with the ammonia, and the lime with the acid
matters. The former dissolves in the water, the latter subsides as a precipitate.
In my experiments, I have found the following procedure good.
Into a pan which will hold, say 150 gallons, and which can be heated by fire or
steam, put 100 gallons of gas tar and raise the temperature to about 100 degrees
Fahrenheit, then into another vessel, say, an open barrel, put 20 gallons of water and
mix with it 10 lbs. of sulphate of line (gypsum or plaster of Paris), put this
mixture into the tar and thoroughly incorporate with it by vigorously stirring for a
few minutes, this is continued till a glass rod dipped in hydrochloric acid and held
over the material produces no white fumes, and if necessary, more sulphate of lime is
added. The watery solution and the tar are now run off into separate vessels and the
precipitate saved and the phenols extracted therefrom by a special process. The
aqueous solution, as it accumulates, is boiled down to produce sulphate of ammonia,
and the tar is mixed with about 10 gallons of petroleum, naphtha, or other light
spirit, and is ready for use as a coating material for iron or steel.
Dated this 12th day of July 1888.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.
COMPLETE SPECIFICATION.
Improved Coating or Preservative Material for Iron, Steel, and other
Structures, or for Coating the Bottoms of Iron and Steel Ships
or other Vessels, and Process of Manufacturing the same and
other Products from Gas Tar.
I, JOHN HUGHES EASTMAN, of 7, Newstead Road, Liverpool, in the County of
Lancaster, Merchant 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 has for its object, a preservative coating material for iron or steel,
that shall be capable of setting into a hard tenacious coat. I use for this purpose gas
tar. This material, however, contains ingredients, such as ammonia and certain acids,
which as long as they remain in the tar, prevent it from forming such a coating.
To remove them, therefore, I add sulphate of lime (plaster of Paris) and water.
These are violently stirred up and intimately mixed with the tar. A double
decomposition occurs, the sulphuric acid combining with the ammonia, and the lime
LD

page_text: with the acid matters. The former dissolves in the water, the latter subsides as a
precipitate.
In my experiments, I have found the following procedure good.
Into a pan which will hold, say 150 gallons, and which can be heated by fire or
steam, put 100 gallons of gas tar and raise the temperature to about 100 degrees
Fahrenheit, then into another vessel, say, an open barrel, put 20 gallons of water and
mix with it 10 lbs. of sulphate of lime, (gypsum or plaster of Paris). Put this
mixture into the tar and thoroughly incorporate with it by vigorously stirring for a
few minutes, this is continued till a glass rod dipped in hydrochloric acid and held
over the material produces no white fumes, and if necessary more sulphate of lime
is added. The watery solution and the tar are now run off into separate vessels.
The precipitate from the solution is saved and the phenols extracted therefrom by a
special process such as the following:
:-
The precipitate is treated with sulphuric acid and water (in about equal pro-
portions), which renders the substance slightly acid. The mass is then fixiviated
with light tar oils and the resulting tarry solution is, after being separated from solid
matter, treated with a solution of caustic soda. The resultant material, after being
separated from the tar oils, is treated with dilute sulphuric acid, whereby the phenols
are liberated, and the latter may afterwards be separated from the watery alkaline
solution by well known methods. The light tar oils can again be used for treatment
of further preparations.
The aqueous solution obtained from the aforesaid treatment of tar is, as it
accumulates, boiled down to produce sulphate of ammonia. The purified tar is nixed
with about 10 gallons of petroleum, naphtha, or other light spirit, and is ready for
use as a coating material for iron or steel.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
1. As a preservative material or coating for steel, iron or the like, gas tar from
which the ammonia and acid matters have been eliminated, dissolved in petroleum-
naphtha or other light spirit, the two combined in the proportion of about 10 to 1,
substantially as described.
2. The process of manufacturing a coating material and other products from gas
tar, which consists in heating the tar to about 100 degrees Fahrenheit, in thoroughly
incorporating it with water and a sufficient quantity of sulphate of lime to neutralise
the ammonia, and in then running off the watery solution from the mixture and
evaporating the same to obtain sulphate of ammonia, separating the tarry matter
from the precipitate and preparing the coating material from said tar and phenols
from the precipitate substantially as described.
3. The improvement in the process of treating tar to free it from acid and alkaline
ingredients which consists in digesting it in water with sulphate of lime.
Dated this 2h day of Aprit 1009.
J. H. EASTMAN.
Wm. P. Thompson & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.