Springfield globe-republic. (Springfield, Ohio) 1884-1887, 1885-06-15
WONDERS OF COAL TAR.
J!orgrnuS Dyes aud Mosi Iscfui Products
Obtalncd From "a Troublesome
Refuse.


Obtaincd From Troublesome
| Refuse.
Chemistry is capable of wonderful
| things" said an expert in chemical
| science, "but in nothing to which its
principles were ever applied have such
marvellous results followed rs are wit
messed in its manipulation OF common
gas or coal tar. Thirty years ago the
problem of how they were to rid tncm-
selves of this foul and then utterly
| useless refuse of the rctOrts was puH-
zling manufacturers of gas. and the
aid Of chemistry was sought in work
ing out the solution. They had no
thought beyond the utter annihilatiOn
of the offensive tar. In their cXpcri-
mont with the refuse the chemists dis
covered the so-callcd burning naptha.
which, however, could be applied with
safety to no practical purpose. After
the naptha was extracted the tar was
left in the form of a heavy oil, which
was still more of a nuisance than the
original compound, rs it was more diff
iicult to store and handle. The chem
St Belief discovered "A channel of util-
ity for this oil in applying it as pickle
for the preservation of railroad ties,
bridge timbrrs, and similarly exposed
woods. This used up large quantities
of the refuse, but only partially relev-
ed the tar nuisance.
The only hope that gas men now
had was that some discovery might be
made in chemical experimenting which
would give a commercial value to tho
refuse. faraday next awokc interest
in coal tar by his discovery of bcnzine
| as product of the tar oil. 1t was
in experimenting with the volatile sub
stances of these oils that the great
chemist Mansfield lost his life, by an
explosion in his laboratory. and it was
probably this casualty that direct
ed greater attention to the possibilities
of the dcspiscd gas tar.
at was not until 1857, however, that
the great value of coal tar as raw
material was demonstrated. In that
year Perkins discovered its aniline
properties, a discovery which has al
mo, t rcvolutionizcd the trade in dye
stutls Perkins took coal-tar naptha,
and, boiling, it in rotort, obtained q
chemical action which resulted in BEN
cole aud nitro-bcnzolc. Adding water
to this, the nitro-bonZole was deposited
in the form of thick. oily mass. This
he experimental with in various ways,
and finally, by the addition of acetic
acid and iron filings, he produced q
colorlcss fluid which is anilinc. The
liquid he treated with different chemic-
al salts, and the result was green crys-
tails of metallic lustcr. These he
found were capable of producing, under
different chemical reactions, the most
brilliant and gorgeous dyeS-tho ami
line hucs Of the paint and dye trades Of
to-day.
This discovery made the long-de-
serted coal tar desirable product of
the gas rctorts, but it held still greater
surprises. From the light oil of the
tar valuable naptha solvent for india
rubber was obtained, and then the in
valuable discovery Of carbolic acid was
made. How many people in ordinary
life know that this great disinfectant is
one of the products of common gas tar?
Aftcr these properties were extracted
from the tar there were left heavy oils
and rcsiduum for which chemistry was
puzzled to find a practical Use. 1t was
not until 1869 that any satisfactory re-
suit was obtained by experimenting
with this refuse, and then the great dis
covery of aliaarine was made. This
product was first obtained by the Ger
man chemists Graebe and Liebermann,
but Prof. Perkins, who had developed
the aniline colors from tar, was the
first to give application to the German
work. The Importance of this discov-
cry may be understood when it is
known that in the first ten years fol-
lowing the introduction of the artificial
alilarlno in the dyestutfs trade, it ex-
cecdcd the total amount of natural ali
zurinc, or maddcr root, that had been
handled in the trade previous to its in
PRODUCTION. 1t was. if anything, supe-
,lor to madder and SO much cheaper
that the saving by Its use up to 1880
had amounted to over $50, 600, 900.
The discovery of aliZarine in coal tar
converted 100000 acres of land that
had been used for growing madder,
root into fertile fields of corn and other
cereals. With vegetable madder it re-
quired nine weeks to perfect the dye
ing of material Turkey red. The ar
titicial maddcr accomplished the de-
sired result in as many hours. Three
years ago the chemist produced an ar
tillcIal indigo from the residuum Of gas
tar, and in connection with the aniline
dyes and alizarine of the same base, it
is rapidly taking the place of indigo.
Later, the napthaline yellows and reds,
with which entirely new effects in col
or were made possible, were derived
from coal-tar rosiduum. Chemists are
still experimenting with the tar pro-
ducts, and other important develop
mcnts will no doubt be made. ~. y
sun.