Russian Journal of Applied Chemistry, 2011, Vol. 84, No. 11, pp. 2011−2012.
Pleiades Publishing, Ltd., 2011.
Original Russian Text © R.I. Yurchenko, A.V. Dolina, A.G. Yurchenko, 2011, published in Zhurnal Prikladnoi Khimii, 2011, Vol. 84, No. 11, pp. 1926−1927.
Inhibiting Action of 1-Phenacylmethyl-2-R-Quinolinium
Bromides at Steel Acid Corrosion
R. I. Yurchenko, A. V. Dolina, and A. G. Yurchenko
National Engineering University of Ukraine “Kiev Polytechnic Institute,” Kiev, Ukraine
Received March 11, 2010
Abstract—Inhibiting action of 1-phenacetylmethyl-2-R-quinolinium bromides at acid corrosion of steel was studied.
A high productivity of searching effective corrosion
inhibitors among multifunctional organic compounds
was noted in a number of works. The presence of several
reaction centers in such compounds capable to react with
a metal surface makes possible a multiplane action of an
inhibitor on the metal surface, providing a high efﬁ ciency
of protective action. Halides of 1-acylmethylpyridinium
having anticorrosive properties described in [1, 2] ap-
peared to be such compounds.
Taking into account similarity of π-electronic systems
of pyridine and quinoline, we could expect that 1-acyl-
methylqinolinium halides also will be effective inhibitors.
It is known  that quinoline, which, alongside with pyri-
dine, is one of by-products of by-product-coking industry,
is rather often used as a corrosion inhibitor of metals.
In the present work the inhibiting action of 1-phenac-
ylmethylqinolinium bromides (1a–1e) was studied.
Here R = H (a), CH
(d), NHCSNHPh (e).
To estimate inhibiting action of compounds under
study, we have determined inhibition coefﬁ cients γ and
degrees of corrosion protection Z of 08 KP steel in the
presence of 1 × 10
M inhibitors in 3 M solutions of
sulfuric acid at 20, 70, and 90°С. Corrosion tests were
fulﬁ lled by a gravimetric method, using steel samples with
a working surface area of 9 × 10
. Duration of tests
was (h): at 20°С 24, at 70°С 2, and at 90°С 1.
Unfortunately, the experiments have shown that
compounds 1a–1e are restrictedly soluble in 3 M H
solutions at room temperature. We were able to reach
the necessary concentration only for compounds 1а– 1c.
At the same time it was found that they are close to the
corresponding pyridinium salts 2а–2c in the level of in-
hibiting effect (see the table). At 70°С the activity of the
compounds under study largely increases, and the role of
the nature of substituents present in salts 1 and 2 becomes
more noticeable. Corrosion inhibition coefﬁ cients in the
series of quinolinium bromides 1а–1e vary from 238.3
up to 314.7, whereas those of pyridinium bromides 2а–2e
vary from 110.9 up to 202.5. It is necessary to note that
compounds 1d and 1e are also scarcely soluble under
these conditions. It seems to be responsible for the fact
that the activity in the series of quinolinium salts increases
by factors of 1.25 and 1.32 on passing from salt 1а to 1d
and 1e, respectively, and for corresponding pyridinium
derivatives 2а and 2d, 2e readily soluble in 3 M H
solutions by factors of 1.69 and 1.86. It has been shown
earlier  that compound 2а retains its activity also at
temperature 90°С. For quinolinium bromides, in particu-
lar for compounds 1c–1e, the level of inhibiting effect
essentially decreases at this temperature. For example, for
amide 1d the corrosion inhibition coefﬁ cient drops from