Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 8, pp. 1401−1407.
Pleiades Publishing, Ltd., 2009.
Original Russian Text
V.N. Esenin, L.I. Denisovich, 2009, published in Zhurnal Prikladnoi Khimii, 2009, Vol. 82, No. 8, pp. 1303−1309.
AND CORROSION PROTECTION OF METALS
Modern technology needs a wide variety of liquid heat
carriers and working bodies with speciﬁ c combinations
of rheological, thermal, and anticorrosion properties
. Ethylene glycol (EG), which provides stable low-
temperature properties, is used as the most readily available
base component for development and manufacture of
promising frost-resistant cooling ﬂ uids and heat carriers
[2, 3]. An important factor in development of new
synthetic ﬂ uids is their compatibility with construction
materials of cooling systems. A complicated problem is
posed by the requirement of simultaneous anticorrosion
protection of different construction materials, including
contact pairs constituted by metals with opposite
Effective anticorrosion properties of a fluid are
provided by choosing appropriate corrosion inhibitors.
The most readily available and effective inhibitors
of metal corrosion in neutral electrolytes are nitrites,
borates, phosphates, and benzoates of alkali metals
. There is a vast body of detailed evidence about the
effect of these inhibitors on the corrosion behavior of
both separate metals and multiple-electrode systems.
However, these data are mostly available for aqueous
electrolytes . Data on the effect of these inhibitors
on the behavior of electrochemically dissimilar metals
in aqueous-organic media are not so abundant [6, 7].
This suggests that a study of the contact corrosion of
metals in aqueous-glycolic solutions of the salts under
consideration is both scientiﬁ cally and practically topical.
Despite certain restrictions on their use in cooling ﬂ uids
for motor cars, introduced by separate countries, these
corrosion inhibitors are widely used in manufacture of
nonﬂ ammable hydraulic and lubricating-cooling ﬂ uids
and in cooling ﬂ uids for heavy-duty vehicles [8, 9].
Planar samples of steel 3 [GOST (State Standard)
380], GH-190 cast iron (VAZ Industrial standard 52205),
AK6M2 aluminum alloy (GOST 1583), M-1 copper
(GOST 859), L-63 brass (GOST 931), and POS-35 solder
[TU (Technical Speciﬁ cation) 48-13-10], with dimensions
of 50 × 25 × 3 mm, were preliminarily polished and
degreased. Corrosion tests were performed in 50 vol %
aqueous-glycolic solutions of corrosion inhibitors by the
galvanostatic dissolution method  and gravimetrically
in conformity with GOST 28084 . The corrosion
rate was evaluated by weighing metal samples. The
following corrosion inhibitors were used: sodium nitrite
(GOST 19906) and sodium tetraborate decahydrate
(GOST 8429), both of technical grade; sodium benzoate
(imported, pure grade); disubstituted sodium phosphate
dodecahydrate (TU 2148-021-05761689–98); and
a system constituted by monosubstituted potassium
phosphate and disubstituted potassium phosphate,
produced by titration of an aqueous-glycolic solution of
potassium hydroxide with orthophosphoric acid to pH
8.0. Ethylene glycol (GOST 19710, extra quality) was
not additionally puriﬁ ed.
Protective Properties of Metal Corrosion Inhibitors
and Their Formulations in Aqueous-Glycolic Solutions
V. N. Esenin and L. I. Denisovich
Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow, Russia
Received February 25, 2009
Abstract—Contact corrosion of a number of metals in aqueous-glycolic solutions of nitrites, borates, benzoates,
and phosphates of alkali metals was studied.