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271
MALEIN AGIDIRID, MONOETANOLAMIN VA FOSFAT KISLOTA MMF-2 MARKALI
KOMPOZIT KORROZIYA INGIBITORINING SINTEZI
1
Choriev I.K.,
2
Turaev Kh. Kh.,
3
Normurodov B.A.,
4
Pardayeva N.J.
1
Faculty of Applied Mathematics and Itellectual Ttechnologies, Termez State University, st.
Barkamol avlod, 43, Termez, Uzbekistan, 190111
,2,3
Faculty of Chemistry, Termez State University, st. Barkamol avlod, 43, Termez, Uzbekistan,
190111
4
Chemistry teacher at School No. 9, Termez city
Corresponding author: Email:
choriyevi@tersu.uz
Abstract.
This article studies the synthesis of corrosion inhibitor based on maleic anhydride,
monoethanolamine and phosphoric acid. The composition of the obtained corrosion inhibitor was
analyzed using IR spectra.
Key words:
maleic anhydride, monoethanolamine, phosphoric acid, corrosion inhibitor.
Introduction
One of the best ways to protect metals from corrosion is the use of corrosion inhibitors. The
use of inhibitors can only slow down corrosion, but cannot completely stop it[1,2]. Corrosion is one
of the processes that cause great damage not only to industry, but also to material and spiritual
heritage. According to their types, corrosion inhibitors are divided into anodic, cathodic and mixed
corrosion inhibitors [3,4]. In general, there are several types of corrosion, which are characterized by
the source of origin and properties. In preventing corrosion, the use of corrosion inhibitors can allow
us to use structures for a relatively longer period of time, but it cannot completely eliminate this
problem [5,6].
Experimental part
This reaction is the opposite of the above process, that is, the process proceeds with the release
of a large amount of heat. It is explained that one of the main reasons for this is not only the high
reaction activity due to the presence of two functional groups in the composition. Based on this
property, a 500 ml flask with a flat bottom is taken, first 2 moles (122 g) of monoethanolamine are
poured into it and the system is cooled in the presence of cooling agents (mainly chilled water). While
stirring the reaction mass, 1 mole (98) of maleic anhydride is slowly added to the reaction mixture.
The mixture was stirred for 45 minutes and the intermediate product was obtained in 92.5% yield
(Figure 1). 1 mol (98 g) of phosphoric acid is slowly added dropwise to the intermediate product
obtained on the basis of monoethanolamine and maleic anhydride, while stirring.
Thermal analysis of MMF-1 composite corrosion inhibitor
The resulting intermediate product has the following physicochemical properties:
Table-2.1.
Physico-chemical properties of MMF-2 brand corrosion inhibitor
№
Aggregate status
pH
Densityg/sm
2
Solvent
MMF-2
An interesting
colored, dark
substance
5,4
1,37
In hot water
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The obtained reaction product was analyzed by IR-spectra methods.
Figure 2.1. IR-spectrum of the intermediate product of MMF-2 corrosion inhibitor.
From the IR spectrum analysis of the intermediate product of MMF-2 corrosion inhibitor, we
can see that the valence vibrations of the OH group were observed in the broad and intense absorption
region of 3059.10cm
-1
. Valence vibrations of -C-N- bonds to the area 1298.09-1182.62 cm
-1
,
asymmetric valence vibrations of -C-O-C- bonds in the area 1298.09 cm
-1
, valence, intensive
vibration frequencies of -C-OH groups 1186.22 cm
-1
valence and intensity fluctuations were observed
in the range of area.
References
1. Nomozov A.K et all. Studying of Properties of Bitumen Modified based on Secondary
Polymer Wastes Containing Zinc. International Journal of Engineering Trends and Technology.
ISSN: 2231–5381 / https://doi.org/10.14445/22315381/IJETT-V71I9P222.
2. Khadom, A.A. Kinetics and synergistic effect of iodide ion and naphthylamine for the
inhibition of corrosion reaction of carbon steel in hydrochloric acid. Reac Kinet Mech Cat. 2015,
115, 463–481. https://doi.org/10.1007/s11144-015-0873-9.
3. Abbas, M.A., Arafa, E.I., Bedair, M.A. et al. Synthesis, Characterization, Thermodynamic
Analysis and Quantum Chemical Approach of Branched N, N′-bis(p-hydroxybenzoyl)-Based
Propanediamine and Triethylenetetramine for Carbon Steel Corrosion Inhibition in Hydrochloric
Acid Medium. Arab J Sci Eng. 2023, 48, 7463–7484. https://doi.org/10.1007/s13369-022-07520-y.
4. Nomozov A, K, et.all. Salsola Oppositifolia acid extract as a green corrosion inhibitor for
carbon
steel.
Indian
Journal
of
Chemical
Technology.
2023,
30,
872-877.
https://doi.org/10.56042/ijct.v30i6.6553.
5. Nomozov Abror, “Production of Corrosion Inhibitors Based on Crotonaldehyde and Their
Inhibitory Properties,” International Journal of Engineering Trends and Technology, vol. 70, no. 8,
pp. 423-434, 2022. https://doi.org/10.14445/22315381/IJETT-V70I8P243.
6. Adawy, A.I., Abbas, M.A. & Zakaria, K. New Schiff base cationic surfactants as corrosion
inhibitors for carbon steel in acidic medium: weight loss, electrochemical and SEM characterization
techniques. Res Chem Intermed. 2016, 42, 3385–3411. https://doi.org/10.1007/s11164-015-2219-7.
“TIBBIYOT OLIYGOHLARIDA TABIIY FANLARNI
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DETERMINATION OF INHIBITION EFFICIENCY OF CORROSION INHIBITOR
BASED ON POLYMETHYL METHACRYLATE
1
Choriev I.K.,
2
Turaev Kh. Kh.,
3
Normurodov B.A.,
4Pardayeva N.J.
1
Faculty of Applied Mathematics and Itellectual Ttechnologies, Termez State University, st.
Barkamol avlod, 43, Termez, Uzbekistan, 190111
,2,3
Faculty of Chemistry, Termez State University, st. Barkamol avlod, 43, Termez, Uzbekistan,
190111
4Chemistry teacher at School No. 9, Termez city
Corresponding author: Email:
choriyevi@tersu.uz
Abstract.
In this article, the inhibition efficiency of the corrosion inhibitor obtained on the
basis of monoethanolamine, methyl methacrylate and phosphoric acid was studied by electrochemical
methods, Electrochemical impedance spectroscopy (EIS) measurements and potentiodynamic
polarization measurements.
Keywords:
monoethanolamine, methyl methacrylate, phosphoric acid, electrochemical
methods, Electrochemical impedance spectroscopy.
Introduction
Corrosion is a reversible process, which converts pure metal to different chemical
compounds[1]. Nowadays, corrosion is turning into a major issue in many industries, building
materials, infrastructure, tools, ships, trains, vehicles, machines, and appliances[2]. Carbon steel
experiences extensive corrosion during the cleansing process with acids. The NACE 2016 reported
that across the world about 2.5 trillion U.S. dollars economic fall due to corrosion and Every year
10% of metal is lost due to corrosion which severely affects the country's economy[3]. Corrosion is
not only responsible for an economic loss but also related with safety issues because it decreases the
shelf life of steel[4]. It has already been recognized as a major issue for the entire world, so researchers
are trying to protect the corrosion process in various ways[5]. Mostly inhibitor is typically used to
protect metal from corrosion and environmental friendly inhibitors have wide application in
corrosion fields and it is generally added in the metal as a low concentration[6]. We believe this study
is a small initiative to find a suitable corrosion inhibitor which can able to protect materials form
corrosion process. According to this study, a corrosion inhibitors were prepared based on poly(methyl
methacrylate-maleic anhydride)P(MMA-MAH)s accompanied with different percentage of methyl
methacrylate and maleic anhydride and the inhibitory potentiality of this inhibitor has checked on
simple carbon steel in a 0.5 M HCl
[7-10].
Materials:
To synthesize this composite corrosion inhibitor, monoethanolamine and methyl
methacrylate monomers (purified by driving in inert nitrogen atmosphere) and phosphoric acid, such
as 1 M HCl for aggressive environments, were used. Steel composition: Fe 97.755-97.215%, C 0.17-
0.24%, Si 0.17-0.37, Mn 0.35-0.65%, Ni 0.3%, S 0.04 %, P 0.035 %, Cr 0.25 %, Cu 0.3 %, As 0.08
%. 2×2.5 cm
2
samples of steel with this composition were taken, the surface was cleaned with
sandpapers, washed several times in acetone and dried.
Methods:
Ushbu korroziya ingibitorining ingibirlash samaradorligini aniqlash uchun
electrochemical studies was performed using devices such as the CS-350 Corrosion test.
Experimental part
Electrochemical studies
Electrochemical impedance spectroscopy (EIS) measurements are a valuable method for
characterizing various electrochemical systems and understanding the function of electrolytic
processes such as batteries and the behavior of molecules during corrosion. Figure 1 shows the
Nyquist plots of St20 at different concentrations for the corrosion study.
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Figure 1 . Nyquist plots of St20 steel in solutions in 1.0 M HCl without and in the presence
of different concentrations of the MMF-1 inhibitor at 298 K
Table 1. Electrochemical impedance spectroscopy parameters of St20 in different
concentrations of MMF-1 compounds and in 1.0 M HCl solutions without inhibitor at 298 K.
Inhibitor
Inhibitor
Concentration
mg/l
E
a
, kJ/mol
ΔH* kJ/mol
ΔS* kJ/mol·K
Without an
inhibitor
0,00
-54,38
-53,69
-12,37
MMF-1
50
-97,56
-94,52
-121,64
100
-106,67
-101,79
-144,68
200
-125,31
-122,36
-203,56
500
-144,89
-137,65
-262,17
The curved rings showed that the corrosion of St20 steel and the formation of surface barriers
were mainly controlled by the electron transfer process. The equivalent circuit model shows in Figure
1. and was used to compare the experimental data on the impedance of St20 steel in the presence of
inhibitors in 1 M HCl. According to model, the solution resistance Rs, charge transfer resistance, R
ct
and the double layer capacitance (C
dl
) on the metal surface were determined. Table 2 clearly explains
that when additives were added to the 1M HCl solution then resistance to charge transfer, R
ct
and
values for ST20 increased as a result the charge transfer pathways were hindered.
Inhibition efficiency, IE(EIS) and θ were calculated using the following formula (1 and 2):
𝐸
𝐸𝐼𝑆
= 𝜃 × 100 = [
𝑅
𝑐𝑡(𝑖𝑛ℎ)
−𝑅
𝑐𝑡(𝑛𝑖𝑛ℎ)
𝑅
𝑐𝑡(𝑖𝑛ℎ)
] × 100
(1)
Here: R
ct
(inh) and R
ct
(ninh) were the resistance to charge transfer in the presence and absence
of inhibitor respectively.
𝐶
dl
= (𝑌
0
𝑅
𝑐𝑡
1−𝑛
)
1
𝑛
(2)
where n was the constant phase element (CPE) indicator and Y
0
was also the CPE constant.
n value between 0 and 1was represented a deviation from ideal behavior. When the inhibitor was
applied then the value of C
dl
decreased which indicated the decreased of the local dielectric constant
and also increased the thickness of the electrical double layer due to forming a protective layer on
the metal surface.
Electrochemical frequency modulation (EFM) is an electrochemical method for calculating
corrosion rates without prior knowledge of Tafel constants. Electrochemical requency
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modulation (EFM) has attracted the attention of corrosion researchers as a promising technique with
high sensitivity due to the measurement of corrosion parameters at harmonics and intermodulations
of input frequencies, as well as high accuracy due to the inherent calculation of causality factors. The
ability of this method is to estimate corrosion rates, Tafel parameters, and causal factors in a single
data set. Table 3 shows the corrosion parameters for protection efficiency, corrosion current density,
Tafel constant, causal factors (CF-2) and (CF-3) for different concentrations in 1M HCl at 298 K.
Table 2. EFM parameters of CT20 in 1.0 M HCl in the absence and presence of
different concentrations of compounds MMF-1 at 298 K
Inhibitor
C
I
corr
βa
βc
K
CF
(2)
CF
(3)
θ
% IE
(EFM)
mg/l
(uA)
(mV
dec
-1
)
(mV
dec
-1
)
mm·y
Without an
inhibitor
–
1071
72,53
94,36
459,87
2,12
3,24
0,92
92,31
MMF-1
50
82,64
52,41
61,25
39,62
1,63
1,95
0,93
93,42
100
74,22
47,62
49,54
32,44
1,49
2,46
0,94
94,33
200
60,56
29,54
33,17
26,53
1,15
2,97
0,95
95,15
500
49,67
15,75
21,48
23,69
1,08
3,12
0,96
96,48
The equation can be used to calculate surface coverage and absorption efficiency
%IE(EFM):
%𝐼𝐸(𝐸𝐹𝑀) = 𝜃 × 100 = (1 −
𝑖
𝑐𝑜𝑟𝑟(𝑖𝑛ℎ𝑖𝑏𝑖𝑡𝑜𝑟𝑠)
𝑖
𝑐𝑜𝑟𝑟(𝑏𝑙𝑎𝑛𝑘)
) × 100
(3)
where i
corr (inhibitors)
and i
corr (blank)
are corrosion current density.
According to Table 3 results, the I
corr
values has decreased with increasing inhibitor
concentration, indicating that, when IE(EFM)) increases then these inhibitors can able to prevent
corrosion by absorbing ST20 on the surface and forming physical and chemical bonds. As a result
the corrosion coefficient decreased and created a protective barrier.
As per the EFM theory, the values of the causal factors (CF-2 and CF-3) were very close to
their theoretical values (according to equation 2 and 3), indicating that the Tafel slopes and the
corrosion current density were correct
[
.
Table 3. Corrosion parameters obtained from potentiodynamic polarization
measurements of St2 steel in 1.0 M HCl at different concentrations of MMF-1 inhibitor at 298
K
Inhibitor
C,
mg/l
βa
(mV
dec
-1
)
βc
(mV
dec
-1
)
I
corr
,
(uA)
Ecorr
vs.SCE
K
(mpy)
Chi
Squared
θ
IE
Without an
inhibitor
–
315
187
4076
-342
1822
87,62
–
–
MMF-1
50
214
238
409
-406
175,6
72,36
0,91 91,13
100
237
223
316
-418
138,4
68,45
0,92 92,37
200
221
289
253
-422
116,3
79,64
0,93 93,46
500
235
302
218
-428
104,5
84,73
0,94 94,72
The polarization curves of St20 in 1 M HCl solution at 298 K with different inhibitor
concentrations were determined using Equation 4.
%𝐼𝐸 (𝑃𝐷𝑃) = 𝜃 × 100 = (1 −
𝑖
𝑐𝑜𝑟𝑟(𝑖𝑛ℎ𝑖𝑏𝑖𝑡𝑖𝑜𝑛)
𝑖
𝑐𝑜𝑟𝑟(𝑓𝑟𝑒𝑒)
) × 100
(4)
Graphs (Figure 6) of the logarithm of the current density were used to draw the polarization
curve. The results of corrosion properties, including corrosion potential (E
corr
), corrosion current
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density (I
corr
), anode and cathode Tafel slopes (
If we plotted potential, E on the vertical axis and log i
horizontally the gradients would be equal to b
a
and b
c
.) and inhibition efficiency percent, %IE (PDP)
are included in the table-3. It has revealed that with the increase in the concentration of inhibitors in
the anode and cathode reactions process, the inhibition efficiency has.
Figure 6. Tafel plot of CT20 at different inhibitor concentrations in 1.0 M HCl solution at 298
K.
increased significantly. This protective barrier was formed by unsaturated bonds to the
heteroatom and inhibitors on the surface of carbon steel. Depending on the type of reaction that often
occurs in an acidic solution, the inhibitor can be an anode, cathode, or mixture. The cathodic process
in which hydrogen gas evolution is observed and the dissolution of metals and the release of electrons
are also happened at anodic process
[17-22]
. The plausible explanation is that the hydrogen evolution
and electrochemical results usually confirm the potential ability of metal dissolution process. In
addition that by controlling the charge transfer charge, hydrogen gas developed in the cathodic
reaction is successfully used as a variable to separate the contribution of hydrogen gas and hydroxyl
ions to the cathodic delamination of the organic coating / inhibitor film.
3. Conclusion.
The MMF-1 corrosion inhibitor based on methyl methacrylate, monoethanolamine, and
phosphoric acid was obtained with a yield of 87% and its structure was firmly established by
spectroscopic techniques. Thermal and electrochemical properties have been studied as well. The
main target of this works is to establish a newly corrosion inhibitor in terms of efficiency against
corrosion process. The final postulations are made by authors which are listed below: The noteworthy
observation was that the obtained composite corrosion inhibitor has been established as 94.72%
Inhibitor efficiency (IE) based on electrochemical analysis method. MMF-1 corrosion inhibitor can
easily use it commercially as a corrosion inhibitor based on its efficiency. However, the authors have
suggested that further testing of the inhibitor's efficiency should be done prior to establish as a
corrosion inhibitor.
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Kouache A., Khelifa A, Boutoumi H, Moulay S, Feghoul A, Idir B, Aoudj S.
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6.
Nurilloev Z., Beknazarov Kh., Nomozov A. Production of corrosion inhibitors based
on crotonaldehyde and their inhibitory properties. International Journal of Engineering Trends and
Technology. 2021, 70, pp. 423-434.
https://doi.org/10.14445/22315381/IJETT-V70I8P243
7.
Nomozov A.K., et all. Studying of Properties of Bitumen Modified based on
Secondary Polymer Wastes Containing Zinc. International Journal of Engineering Trends and
Technology. ISSN: 2231–5381 / https://doi.org/10.14445/22315381/IJETT-V71I9P222.
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Nomozov A.K., et all. Study of processes of obtaining monopotassium phosphate
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Nurilloev Z., Beknazarov Kh., and Nomozov A., "Production of Corrosion Inhibitors
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Trends
and
Technology.,
2022,
vol.
70,
8,
pp.
423-434,
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https://doi.org/10.14445/22315381/IJETT-V70I8P243.
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https://doi.org/10.56042/ijct.v30i6.6553
