Journal of Bio- and Tribo-Corrosion (2022) 8:78
https://doi.org/10.1007/s40735-022-00675-z
Citrullus colocynthis Ethanolic Extract as an Ecological Inhibitor
of Carbon Steel C38 Corrosion in Hydrochloric Medium
Hefdh aldeen Al‑sharabi1,2 · Khalid Bouiti1 · Fatima Bouhlal1 · Najoua Labjar1 · Abdelwahed Dahrouch3 ·
Mohammed El Mahi1 · El Mostapha Lotfi1 · Bouchaib El Otmani1 · Ghita Amine Benabdellah1 · Souad El Hajjaji3
Received: 1 October 2021 / Revised: 25 April 2022 / Accepted: 11 May 2022 / Published online: 15 June 2022
© The Author(s), under exclusive licence to Springer Nature Switzerland AG 2022
Abstract
The inhibitory potency of Citrullus colocynthis ethanolic seed extract (COCO) against corrosion of C38 steel in a hydrochloride media was studied by impedance spectroscopy (EIS) and potentiodynamic polarization (PDP). The polarization data
demonstrated a mixed inhibitory behavior. Both polarization and EIS showed excellent agreement in inhibitory efficiency,
with IE percent values of 94.9 and 95.8% at 2 g/L COCO extract. The adsorption follows the Langmuir model based on the
isothermal analysis. The impact of time was also tested to ensure the inhibitor's stability for 72 h, and the study showed that
COCO extract had sufficient stability to be used as an inhibitor. A GC–MS study of the extract and an SEM/EDX investigation of the metal surface were done to further understand this impact. The results of the GC–MS test revealed the existence
of various chemicals that might be responsible for the inhibitor's corrosion-inhibiting properties. The presence of a protective
barrier formed on the surface by adsorption of active COCO molecules has been established by SEM/EDX measurements.
Keywords C38 steel · Citrullus colocynthis extract · EIS · Tafel · Corrosion · 1 M HCl
1 Introduction
Corrosion is a cross-disciplinary issue, [1, 2]. Corrosion is
produced by the environment's chemical and electrochemical effects on metals and alloys [3]. The implications are
serious in a range of sectors, as well as an industry: production shutdowns, component replacements, accidents, and
environmental concerns are all common occurrences with
potentially severe economic consequences [4, 5]. Despite
the high mechanical strength and cheap cost, the majority of steel alloys are used in a broad variety of production
* Najoua Labjar
najoua.labjar@ensam.um5.ac.ma
1
Laboratory of Spectroscopy, Molecular Modeling, Materials,
Nanomaterials, Water and Environment, CERNE2D,
ENSAM, Mohammed V University in Rabat, Rabat,
Morocco
2
Laboratory of Chemistry, MinistryofEducation, Jamal
Abdulnasser High School, Sanaa, Yemen
3
Laboratory of Spectroscopy, Molecular Modeling, Materials,
Nanomaterials, Water and Environment, CERNE2D, Faculty
of Sciences, Mohammed V University in Rabat, Rabat,
Morocco
processes, such as engineering, construction, and military
applications [6].
Notwithstanding this, it is affected by its environment,
especially acidic ones, which accelerates the decomposition
(corrosion) [7]. Acid solutions are used in industries such as
pickling, chemical cleaning and refining, ore extraction, and
oil well acidification [8].
Corrosion inhibitors are used to keep metals from corroding. Inhibitors are chemical agents that are added to a
medium in trace levels to prevent materials from corroding.
For permanent or temporary prevention (particularly when
the substance is severely corrosive or subjected to harsh conditions) [9, 10].
For example, chromates, dichromates, nitrites, and
nitrates can be employed in different situations and with a
broad range of materials.
However, these chemicals' biotoxicity and non-environmental properties, notable chromates, have been extensively studied, limiting their use [11]. Corrosion research in
recent years has centered on creating low-cost, ecologically
friendly chemicals [12]. Because of their environmental
sustainability, low toxicity, and low cost, plant extracts are
considered promising solutions to the problem of metal corrosion in many media, particularly acidic ones [13–16].
13
Vol.:(0123456789)
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
78 Page 2 of 11
Journal of Bio- and Tribo-Corrosion (2022) 8:78
Scanning electron microscopy and electrochemical
polarization and impedance measurements were used to
analyze the inhibitory impact of an ethanolic extract of
Citrullus colocynthis (COCO) in a 1 M hydrochloric acid
(HCl) media both as a natural inhibitor of C38 corrosion.
2 Methods and Materials
2.1 Inhibitor Preparation
50 g of crushed dry grains were steeped in a beaker containing 99% for two ethanol and then filtered through filter
paper. The filtrate solution was evaporated via a rotary
evaporator at 67 °C until dry, then weighted and stored for
later use. The yield was determined for the economic aim
using the following Eq. (1), C. colocynthis has a beneficial cucurbit plant that has abundantly distributed over the
world's arid regions [17], including Morocco [18]. Has a
diverse array of medicinal properties. Obesity, respiratory
diseases, and diabetes are treated with seeds and fruit [19].
The main chemical contained in seeds is a fixed oil such as
Fatty acid-like Myristic, Linoleic, oleic, Stearic, Palmitic,
Linolenic acid [20], Methylene chloride, Cyclopentanol,
2-methyl-, trans [21], p-Terphenyl [22]. The C. colocynthis
(L.) Schrade (COCO) plant was chosen as the subject of
our article based on the chemical components contained
in its fruit. The ecological inhibitory effect of COCO ethanolic extract on C38 steel corrosion in 1 M HCl solution
was evaluated using morphological and electrochemical
techniques [23]:
Y=
mfin
× 100
mint
(1)
where mfin is the mass of the extract after solvent evaporation, and mint is the sample mass before extraction. The
extraction yield was 15%.
2.2 Electrode and Solution Corrosive
Corrosion studies on Carbon steel electrodes with the
respective chemical compositions (in weight%) were conducted: C makes up 0.37, Mn makes up 0.68, S makes up
0.016, Cr makes up 0.077, Si makes up 0.23, Co makes
up 0.009, Cu makes up 0.16, Ni makes up 0.059, and Ti
makes up 0.011, and the remainder is iron. Abrasive sheets
(1200–2000) were used to polish the electrodes before
washing, degreasing with ethanol, and drying with hot air.
The solutions (1 M HCl) were made by diluting a 35% HCl
analytical reagent with doubly distilled water.
2.3 Electrochemical Analysis
Measurement was performed using an EC-Lab softwarecontrolled VMP3-Biologic potentiostat. There was a C38
steel sample as the working electrode (WE), a platinum
wire as the counter electrode (CE), and an SCE as the reference electrode (RE). For each test, the (WE) was allowed
to corrode freely for 30 min, this value represents the time
required for the open circuit potential to reach a quasi-stationary value. For the polarization plot, the potential was
changed at a rate of 0.5 mV/s. Equation (2) gives the inhibitor efficiency IE (%) [24]:
)
(
i
IE(%) = 1 − inh × 100
(2)
icorr
where icorr and iinh are attributed to the current density of
C38 corrosion collected by extrapolating the Tafel lines with
and without inhibitor.
Electrochemical impedance spectroscopy graphs were
acquired from 100 kHz to 10 mHz. Based on Rct values [25],
the efficiency was calculated using Eq. (3).
)
(
Rct
× 100
IE(%) = 1 −
(3)
Rctinh
where Rct and Rctinh are the resistances of charge transfer
values of C38 without and with COCO extract.
2.4 Determination of Chemical Compounds
by GCMS Analysis
A gas chromatograph (TRACE 1300) coupled to a mass
spectrometer (triple quadripole tsq 8000 evo) was adopted
for this purpose, with a VB-5 (30 m 0.25 mm 0.25 m) column and helium as carrier gas (1.4 mL/min). The injector and interface were 220 °C and 300 °C. To separate the
COCO extract components, the column was heated from 40
to 180 °C (4 °C/min), then 300 °C (20 °C/min) for 2 min.
The material was split-mode injected (1 μL) and the mass
spectrometry detector was set to 70 eV. The compounds
The COCO extract chemicals were determined by evaluating their relative retention time and mass spectra to the
database's analytical standards.
2.5 Surface Analysis
A succession of emery paper (220,400, 600, 1000 & 2400
grade) was used to scrape the carbon steel specimens, followed by cleaning in distilled water/acetone. After 24 h in
1 M HCl in the absence and presence of COCO extract,
the surface morphology and chemical composition of C38
13
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
Page 3 of 11 78
Journal of Bio- and Tribo-Corrosion (2022) 8:78
steel specimens were examined using an FEI- Quanta 650
scanning electron microscope with energy-dispersive x-ray
spectroscopy (SEM–EDX).
3 Results and Discussion
3.1 Extraction Yield
The active components of C. Coloynthis were extracted by
different methods (COCO). The maceration method was
chosen because it is more cost-effective and economical,
which fits the objective of the study (cheap and environmentally friendly extract) and makes our work practices.
The percentage extraction yield was calculated using Eq. (1).
inhibitory efficiency of steel in a 1 M HCl environment without and with varying concentrations of COCO extract. Figure 2 illustrates the polarization curves of C38 steel in 1 M
HCl without and with various amounts of COCO extract. As
indicated, the log I = f (E) curves for COCO extract concentration have a similar shape.
The electrochemical parameters and inhibitory efficiency
at various concentrations are shown in Table 1. Equation (2)
determines the corrosion inhibitory efficiency IE (%). According to the first analysis of these curves, the inhibitor's presence alters the anodic and cathodic reactions. The anodic and
cathodic currents decrease with concentration. The reaction
below [28, 29] expresses the metal (anode) deterioration:
(4)
Fe(s) → Fe2+ (aq) + 2e−
3.2 Concentration Effect
Cathodic reduction is the reduction of hydrogen ions in
solution to dihydrogen, as shown below:
3.2.1 Open Circuit Potential
2H+(aq) + 2e− → H2(g)
(5)
Throughout each electrochemical test, the system must
be stabilized to get the steady-state potential and its timedependent progression. According to Fig. 1, the potential adopts a rapid stabilization trend with a variation
of the extract concentration [26], the measured value is
between − 0.42 V/ECS and − 0.47 V/ECS, and the progression with the blank indicates a mixed character of inhibition
[27].
3.2.2 Polarization Measurements
At room temperature, the polarization curve was utilized to
characterize the electrochemical properties and corrosion
Fig. 2 Polarization curves of C38 steel in 1 M HCl with and without
COCO extract
Table 1 Electrochemical parameters of C38 steel in hydrochloride
solution containing different amounts of COCO extract
Fig. 1 The temporal progression of the open circuit potential (EOCP)
at different concentration
Concentration
(g/L)
Icorr (µA.
cm−2)
− Ecorr
(mV/
SCE)
βa (mV) − βc (mV) IEPDP (%)
Blank
0.25
0.5
0.75
1
1.5
2
482.5
82.3
42.3
41.1
37.7
30.7
24.7
452.9
474.3
447.6
451.4
436.6
469.2
423.6
126.3
78.1
67.2
67.1
66.7
74.2
61.8
136.0
143.2
126.0
115.3
118.8
134.9
116.3
–
82.9
91.2
91.5
92.2
93.6
94.9
13
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
78 Page 4 of 11
Journal of Bio- and Tribo-Corrosion (2022) 8:78
The linear component of the cathode curves (Tafel
line) in our instance indicates that the hydrogen reduction
process at the steel surface is a pure activation mechanism
[25].
Although the inhibitor reduces current density, the
small variation of the cathodic Tafel slopes suggests that
the process of protons reduction at the steel surface is
unaffected and occurs through a pure activation mechanism [30] as shown in Table 1. Inhibitors appear to adsorb
to the steel surface first, then function by blocking the
surface's active sites. Schiff bases [31], thiadiazole [32],
Tryptamine [33], and Geissospermum laeve electrochemical and phytochemical experiments employing the same
steel and media [2] have all been shown to have similar
effects. In the same way, introducing inhibitors to the
anode field reduces the anode current density. Furthermore, in the event of a severe anode overvoltage, we see
the presence of two linear sections for allconcentrations
examined (Fig. 1). The anode current density quickly
rises when desorption potential Ed (potentials larger than
− 0.300 V/SCE) is surpassed [11, 12]. This behavior has
been seen for steel in chlorhydric acid [1, 34, 35].
The anodic current rises rapidly after the potential Ed
because of the desorption of inhibitor adsorbing on the
metal surface. Desorption of the inhibitor from the metal
surface does not promote corrosion because anodic current densities are less than blank densities.it still prevents
corrosion, demonstrating that inhibitor adsorption and
desorption are influenced by electrochemical potential.
3.2.3 Electrochemical Impedance Spectroscopy (EIS)
Impedance experiments are a straightforward technique that has
been frequently utilized to investigate inhibition mechanisms
[36]. It provides information on the resistive and capacitive
behavior of the contact, which enables the estimation of the studied compounds' efficiency as probable metal corrosion inhibitors
[3, 37, 38]. The Nyquist and Bode graphs generated from the EIS
examination of C38 steel in 1 M HCl solution using different
amounts of COCO extract are shown in Figs. 3 and 4.
Figure 4 shows a semicircle curve relative to the capacitive
loop in all Nyquist diagrams constructed with and without
the inhibitor. The interfacial impedance frequency dispersion
causes imperfect semicircles in the impedance diagrams [39].
The blank and COCO curves are similar in form, indicating
that the COCO extract did not affect the corrosive medium.
Capacitive loops expand when COCO extract concentration increases. The electrical chemistry characteristics of the
Nyquist and Bode curves were obtained using an EEC (Fig. 5).
A coefficient of 10–3 to 10–2, which justifies the models, was
induced in the EEC utilized [40, 41].
R1, R2, and Q2 in the analogous circuit signify the electrolyte resistance, charge transfer resistance, and constant phase
element, respectively, which reflect the capacity of the double
layer at the metal/solution interface. To account for non-ideal
behavior induced by surface inhomogeneity, roughness, porosity, and adsorption on C38 steel, "Q" was employed instead of
a double layer capacity (Cdl) [23] (Eq. 6).
Cdl =
𝜀𝜀0
S
e
Fig. 3 C38 Nyquist plots in 1 M
HCl (A) and 0.5-2 g/L COCO
extract (B)
13
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
(6)
Page 5 of 11 78
Journal of Bio- and Tribo-Corrosion (2022) 8:78
Fig. 4 C38 in 1 M HCl bode graphs within the presence and absence of COCO extract
Table 3 Bode parameters for carbon steel in hydrochloride solution in
the absence and presence of COCO extract
Fig. 5 Equivalent C38 circuit in HCl 1 M interface with and without
COCO extract
where (e) represents the interfacial layer thickness, (S) the
electrode surface area, (ε0) the medium permittivity, and ε
the dielectric constant.
Table 2 shows the results of processing the Nyquist
curves using the electrical circuit represented in Fig. 4. The
COCO extract appears to have just a slight influence on the
electrolyte resistance (Rs) in the table, demonstrating that the
inhibitor used satisfies the requirement of being trustworthy without affecting the solution's physicochemical qualities. The addition of the COCO extract, on the other hand,
increases charge transfer resistance, showing that the extract
has a corrosion-preventative impact on C38 steel.
Also, according to Helmholtz's model (Eq. 6), a drop in
­Q2 indicates a decrease in the dielectric constant, and hence
Solution
ϴmax (deg)
Freqmax (Hz)
Slope
Blank
0.25
0.5
0.75
1
1.5
2
68.2
55.4
61.8
64.3
68.2
68.5
46.8
2.3
2.1
1.9
2.3
2.1
1.9
2.1
− 0.8
− 0.6
− 0.7
− 0.7
− 0.7
− 0.6
− 0.5
a rise in the double layer thickness. We can also observe that
as concentration climbs, so does inhibition efficiency.
In Nyquist curves, the Bode modulus plot corresponds
to the semicircle diameter graph (Fig. 4). Only one-time
constants were discovered, and a consistent appearance
across all cases indicated that adding COCO inhibitor had
no influence on the corrosion mechanism, indicating that
charge transfer is guided by this process [41, 42]. Moreover,
the shape of these graphs reveals three distinct segments,
the first of which is located at a higher frequency, meaning that both phase angle and log |Z| tend to be near zero,
which may be due to the electrolyte's resistive activity and
Table 2 Electrical parameters were determined by the fit of Nyquist plots of C38 steel in 1 M hydrochloric acid without and with COCO extract
Concentration (g/L)
Rs (Ω ­cm2)
Blank
0.25
0.5
0.75
1
1.5
2
2.9 ± 0.4
4.6 ± 0.3
4.5 ± 0.3
2.8 ± 0.3
5.1 ± 0.2
3.2 ± 0.2
3.6 ± 0.3
Q2 (F/cm2)
0.35 ­e−3 ± 81.7 ­e−6
0.17 ­e−3 ± 6.02 ­e−6
0.15 ­e−3 ± 5. ­2e−6
0.10 ­e−3 ± 1.9e−6
98.8 ­e−6 ± 1.2 ­e−6
90.2 ­e−6 ± 0.85 ­e−6
0.10 ­e−3 ± 0.6 ­e−6
n
Rct (Ω ­cm2
IEEIS (%)
0.83
0.80
0.82
0.84
0.80
0.82
0.83
36.8 ± 0.7
172.9 ± 0.5
190.5 ± 0.6
306.2 ± 0.5
502.0 ± 0.6
558.9 ± 0.5
869.5 ± 0.6
–
78.7
80.7
88.0
92.7
93.4
95.8
13
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
78 Page 6 of 11
Journal of Bio- and Tribo-Corrosion (2022) 8:78
Table 4 Surface coverage on
the increasing concentration of
COCO extract
Cinh
θ
0.25 g/L
0.5 g/L
0.75 g/L
1 g/L
1.5 g/L
2 g/L
0.83
0.91
0.91
0.92
0.93
0.95
at low frequencies, suggesting an increase in the electrode's
resistive resistance [43, 44]. Table 3 summarizes all of the
electrochemical properties determined from bode graphs.
The efficiencies obtained by the EIS and PDP studies are
slightly different at intermediate concentrations and similar at high concentrations, and their evolution indicates an
agreement between the 2 techniques.
3.2.4 Adsorption Isotherms
Table 5 Correlation coefficients for Temkin, Frumkin, and Langmuir
adsorption isotherm
Isotherm
2
R
Temkin
Frumkin
Langmuir
0.8514
0.8902
0.9997
resistance. In the second part, the phase angle increases as
the concentration of COCO extract increases, showing that
more inhibitor molecules adsorb on the C38 steel surface
[28]. Also, the phase angle values (Table 3) are less than
90°, with linear slope correlation values less than (1), indicating that the corrosion process is rough on the steel C38
surface, reducing the phase angle. As a frequency function,
log |Z| approaches infinity with the third component, located
An inhibitor adsorbs in aqueous solutions through quasisubstitution of the organic component in the solution with
the water molecules on the electrode surface [45, 46].
An isotherm was used to evaluate the association between
surface coverage and extract concentration (Cinh) and test
different models (Frumkin, Temkin, and Langmuir).
The degree of cover on the metal surface is given by (θ),
obtained from polarization measurements in Eq. (7) [47].
Table 4 shows the surface coverage against COCO extract
concentration:
𝜃=
IE
100
Fig. 6 Adsorption isotherms of Langmuir (A), Temkin (B), and Frumkin (C) with inhibitor
13
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
(7)
Page 7 of 11 78
Journal of Bio- and Tribo-Corrosion (2022) 8:78
The correlation coefficients for the various models examined are shown in Table 5; the correlation was achieved by
Langmuir's isotherm (Fig. 6, Table 5) with an R2 = 0.9997.
Table 5 shows the correlation factors for the different
models studied; the best fit was provided by Langmuir's
isotherm (Fig. 6, Table 5) with an ­R2 = 0.9997, according to
the following equation [48]:
Cinh
1
+ Cinh
=
𝜃
Kads
(8)
The Langmuir model assumes that the adsorbed inhibitor monolayer is put on a homogeneous solid surface, without any contact in both the adsorbed molecules, and each
inhibitor molecule occupies an active site, an anode site,
and a cathode site without difference [49]. The adsorption
constants can be obtained from the intercept, with Kads = 25
L/g, according to Eq. (8).
The extract contains many substances, due to the difficulty in identifying the molecular weight of the extract,
which makes determining the free enthalpy of adsorption
(ΔG°ads) impossible [50], various studies have cited the
same issue when analyzing natural extracts [2, 51].
3.3 Inhibition Efficiency as a Function of Immersion
Time
An immersion period is a measure used to ensure that inhibitory characteristics are conserved and to assess long-term
stability at the solution-metal interface [2].
The durability of the protective covering formed on the
metallic surface may be assessed by measuring the change
in charge transfer resistance after various immersion times
in a harsh environment [39].
Figure 7 shows the electrochemical impedance curves for
C38 steel obtained after immersion in 1 M HCl medium with
2 g/L COCO extract for (2, 4, 6, 18, 24, and 72) hours.
The electrical equivalent circuits shown in Fig. 7, (a):
blank for 2;4;6;18, and 2;4;6;18;24 with COCO extract (b):
blank for 2;4;72, and 72 with COCO extract) were used to
acquire usable digital data. We can model the process at the
interface (C38-Solution), adjust the experimental diagrams
based on the correlation coefficient X2 = ­10–3, and extract the
necessary parameters.
As illustrated in Fig. 7, we collected two distinct electrochemical tendencies and expressed them using two equivalent circuits a and b; in both models, R1 represents the
solution resistance, R2 the layer resistance, R3 the faradic
reaction, and Q1, Q2, and Q3 the constant phase components
that characterize the double layer capacity at the C38/solution interface.
All collected parameters are grouped in Table 6 after
curve processing. As indicated in the table, electrochemical
parameter values were determined by the use of comparable circuits models. According to Table 4, the value of the
inhibited solution's charge transfer resistance increases over
the course of 24 h, with the inhibitory efficiency maximum
at 24 h.
The deposition of COCO extract to the C38 surface and
water molecules displacement by acid ions ­(Cl−) initiate this
reaction [52]. We also find a drop in both Q1 and Q2 values
compared to the blank at the same immersion periods, which
is due to the development of a double-layer capacitor with a
protective coating on the metal surface.
3.3.1 Determination of Chemical Compounds by GCMS
Analysis
Fig. 7 Nyquist diagram of C38 steel at different immersion times
According to the obtained results, the treated extract contains different active molecules, such as: nerolidol, verticiol,
thunbergol, marsectohexol; esters: n-octyl acetate, diethyl
phthalate, ethyl linolenate, and other components (Fig. 8).
According to various studies, the inhibitor efficiency
could be connected to the presence of n-octyl acetate, nerolidol, ethyl linoleate in the studied extract [53, 54]. It should
be noted that the inhibitory effect can be attributed also to a
synergistic action between the different molecules present in
the extract. Surface observation via SEM/EDX.
SEM images were taken of C38 steel after 24 h in 1 M
HCl without and with COCO extract. The specimen's surface
morphology was considerably affected by 1 M hydrochloride
acid. As seen in Fig. 9. (a) The surface was smoother and
had few pits after immersion in an acidic solution with 2 g/L
COCO extract (Fig. 9). (b) The smoothness of the inhibited
C38 surface is due to the protective layer development.
13
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
78 Page 8 of 11
Journal of Bio- and Tribo-Corrosion (2022) 8:78
Table 6 Electrochemical impedance spectroscopy parameters and efficiency inhibition (IE%) for C38 in1 M HCl with 2 g/L of COCO extract at
various immersion times
Immersion Time
R1 (Ω ­Cm2)
Blank
2H
11.16
4H
10.96
6H
10.3
18 H
7.662
24 H
4.01
72 H
7.11
2 g/L of COCO extract
2H
4.67
4H
5.92
6H
0.61
18 H
6.59
24 H
4.63
72 H
5.75
R2 (Ω C
­ m2)
R3 (Ω C
­ m2)
104 Q2 (F ­cm−2)
n2
104 Q3 (F ­cm−2)
n3
Rct (Ω ­Cm2)
IE%
116.2
222.5
283.3
310.4
168
26.66
_
_
_
_
6.104
19.24
2.727
2.214
2.146
1.413
2.278
1.186
0.8
0.8
0.8
0.9
0.8
0.9
_
_
_
_
155.4
118.1
_
_
_
_
0.8
0.7
116.2
222.5
283.3
310.4
174.1
45.9
_
_
_
_
_
_
158.1
468.3
642.6
920.2
1410
165
–
–
–
–
–
237.2
2.2
2.1
0.9
0.6
0.5
1.1
0.8
0.8
0.9
0.8
0.9
0.9
–
–
–
–
–
1.476
–
–
–
–
–
0.9
158.1
468.3
642.6
920.2
1410
402.2
22.2
51.4
55.1
61.2
88.0
88.6
Fig. 8 GC/MS chromatographic profile of the ethanolic extract
Energy Dispersive X-ray analysis was used to investigate the surface composition of C38 before and after the
protective layer [55]. The EDX peaks (Fig. 10a) confirm a
dissolution of the C38 components (presence of iron and
carbon) [37].
13
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
Page 9 of 11 78
Journal of Bio- and Tribo-Corrosion (2022) 8:78
Fig. 9 SEM images of C38 in
acidic solution without (a) and
with 2 g/L COCO inhibitor (b)
Fig. 10 EDX spectrum of C38 in acidic solution without (a) and with (b) 2 g/L COCO inhibitor (b)
By comparing a and b of Fig. 10, the significant decrease
in the iron peak indicates that the metallic surface is protected
from further damage. The decrease in the Cl and O peaks is
related to the development of a complex with iron due to the
metal's degradation (FeClOH). Due to the adsorbed organic
substance on the surface. Peak carbon increased after the addition of the COCO extract [56].
4 Conclusion
The purpose of this work is to investigate the inhibitory
activity of a colocynthis seed extract in a 1 M HCl medium
by altering the concentration and duration of the immersion using an electrochemical approach. The results show
that:
• The variation of the concentration produces an increase
in inhibitory efficiency and attains a maximum of
94.9% at 2 g/L, acting as a mixed type inhibitor that
could be connected to its phytochemical constituents.
• The adsorption of the active molecules is carried out
according to the Langmuir isotherm.
• COCO is relatively stable throughout time (88 percent
after 24 h of immersion), by the creation of a barrier
layer on the surface as demonstrated by scanning electron microscopy and X-ray diffraction.
Funding The authors declare that no funding was awarded to this study.
Data Availability The datasets generated during and/or analysed during the current study are available from the corresponding author on
reasonable request.
Declarations
Conflict of interest The authors have not disclosed any competing interests.
13
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
78 Page 10 of 11
Journal of Bio- and Tribo-Corrosion (2022) 8:78
References
1. Labjar N, Lebrini M, Jama C, Bentiss F, Idrissi M, EL Hajjaji S
(2015) Evaluation of the inhibitor synergetic effect of aminotris
(methylenephosphonic) acid and metallic salts on the corrosion
of iron in acidic medium. J Mater Environ Sci 6:2604
2. Faustin M, Maciuk A, Salvin P, Roos C, Lebrini M (2015) Corrosion inhibition of C38 steel by alkaloids extract of Geissospermum
laeve in 1M hydrochloric acid: electrochemical and phytochemical
studies. Corros Sci 92:287–300. https://​doi.​org/​10.​1016/j.​corsci.​
2014.​12.​005
3. Debab H (2018) Electrochemical and quantum chemical studies
of adsorption and corrosion inhibition of two new Schiff bases on
carbon steel in hydrochloric acid media. Int J Electrochem Sci.
https://​doi.​org/​10.​20964/​2018.​07.​19
4. Al-Moubaraki AH, Obot IB (2021) Top of the line corrosion:
causes, mechanisms, and mitigation using corrosion inhibitors.
Arab J Chem 14(5):103116. https://d​ oi.o​ rg/1​ 0.1​ 016/j.a​ rabjc.2​ 021.​
103116
5. Cabrera-Sierra R, Garcı́a I, Sosa E, Oropeza T, González I (2000)
Electrochemical behavior of carbon steel in alkaline sour environments measured by electrochemical impedance spectroscopy.
Electrochim Acta 46(4): 487‑497. https://d​ oi.​org/1​ 0.1​ 016/​S0013-​
4686(00)​00567-3
6. Fattah-alhosseini A, Noori M (2016) Corrosion inhibition of SAE
1018 carbon steel in H
­ 2S and HCl solutions by lemon verbena
leaves extract. Measurement 94:787–793. https://​doi.​org/​10.​
1016/j.​measu​rement.​2016.​09.​02
7. Song Y, Jiang G, Chen Y, Zhao P, Tian Y (2017) Effects of
chloride ions on corrosion of ductile iron and carbon steel in
soil environments. Sci Rep 7(1):6865. https://​doi.​org/​10.​1038/​
s41598-​017-​07245-1
8. Finšgar M, Jackson J (2014) Application of corrosion inhibitors
for steels in acidic media for the oil and gas industry: a review.
Corros Sci 86:17–41. https://d​ oi.o​ rg/1​ 0.1​ 016/j.c​ orsci.2​ 014.0​ 4.0​ 44
9. Hossain N, Asaduzzaman Chowdhury M, Kchaou M (2021) An
overview of green corrosion inhibitors for sustainable and environment friendly industrial development. J Adhes Sci Technol
35(7):673–690. https://​doi.​org/​10.​1080/​01694​243.​2020.​18167​93
10. Panchal J, Shah D, Patel R, Shah S, Prajapati M, Shah M (2021)
Comprehensive review and critical data analysis on corrosion and
emphasizing on green eco-friendly corrosion inhibitors for oil and
gas industries. J Bio- Tribo-Corros 7(3):107. https://​doi.​org/​10.​
1007/​s40735-​021-​00540-5
11. Kadhum A, Mohamad A, Hammed L, Al-Amiery A, San N, Musa
A (2014) Inhibition of mild steel corrosion in hydrochloric acid
solution by new coumarin. Materials 7(6):4335–4348. https://​doi.​
org/​10.​3390/​ma706​4335
12. Raja PB, Sethuraman MG (2008) Natural products as corrosion
inhibitor for metals in corrosive media A review. Mater Lett
62(1):113–116. https://​doi.​org/​10.​1016/j.​matlet.​2007.​04.​079
13. Płotka-Wasylka J, Rutkowska M, Owczarek K, Tobiszewski M,
Namieśnik J (2017) Extraction with environmentally friendly
solvents. TrAC Trends Anal Chem 91:12–25. https://​doi.​org/​10.​
1016/j.​trac.​2017.​03.​006
14. Wei H, Heidarshenas B, Zhou L, Hussain G, Li Q, Ostrikov K
(Ken) (2020) Green inhibitors for steel corrosion in acidic environment: state of art. Mater Today Sustain 10: 100044. https://d​ oi.​
org/​10.​1016/j.​mtsust.​2020.​100044
15. Verma C, Ebenso EE, Bahadur I, Quraishi MA (2018) An overview on plant extracts as environmental sustainable and green
corrosion inhibitors for metals and alloys in aggressive corrosive
media. J Mol Liq 266:577–590. https://​doi.​org/​10.​1016/j.​molliq.​
2018.​06.​110
16. Siti Zuliana S, Abdul Hafidz Y, Siti Koriah Z, Mustapha AAT,
Anasyida AS, Mohamad NM, Mardawani M, Sarizam M, Sharizal
AS, Arlina A, Pao TT (2021) Plant extracts as green corrosion
inhibitor for ferrous metal alloys: a review. J Clean Prod. https://​
doi.​org/​10.​1016/j.​jclep​ro.​2021.​127030
17. Hussain AI, Rathore HA, Sattar MZA, Chatha SAS, Sarker SD,
Gilani AH (2014) Citrullus colocynthis (L.) Schrad (bitter apple
fruit): a review of its phytochemistry, pharmacology, traditional
uses and nutritional potential. J Ethnopharmacol 155(1):54–66.
https://​doi.​org/​10.​1016/j.​jep.​2014.​06.​011
18. Belhaj S, Chaachouay N, Zidane L (2021) Ethnobotanical and
toxicology study of medicinal plants used for the treatment of diabetes in the High Atlas Central of Morocco. J Pharm Pharmacogn
Res 9:619
19. Ahmed M (2019) Phytochemical screening total phenolic and
flavonoids contents and antioxidant activities of Citrullus Colocynthis L and Cannabis Sativa L. Appl Ecol Environ Res. https://​
doi.​org/​10.​15666/​aeer/​1703_​69616​979
20. Pravin B, Tushar D, Vijay P (2013) Review on Citrullus colocynthis. Int J Res Pharm Chem 3:46
21. Bourhia M, Messaoudi M, Bakrim H, Mothana RA, Sddiqui NA,
Almarfadi OM, El Mzibri M, Gmouh S, Laglaoui A, Benbacer L
(2020) Citrullus colocynthis (L.) schrad : chemical characterization, scavenging and cytotoxic activities. Open Chem 18(1):986–
994. https://​doi.​org/​10.​1515/​chem-​2020-​0124
22. Rizvi TS, Ali L, Al-Rawahi SS, Al-Harrasi A (2017) New p -terphenyl from the fruit of Citrullus colocynthis (Cucurbitaceae). Nat
Prod Commun 12(7):1934578X1701200. https://d​ oi.o​ rg/1​ 0.1​ 177/​
19345​78X17​01200​724
23. Bouhlal F, Labjar N, Abdoun F, Mazkour A, Serghini-Idrissi M,
Mahi ME, Lotfi EM, Skalli A, El Hajjaji S (2020) Chemical and
electrochemical studies of the inhibition performance of hydroalcoholic extract of used coffee grounds (HECG) for the corrosion
of C38 steel in 1M hydrochloric acid. Egypt J Pet 29(1):45–52.
https://​doi.​org/​10.​1016/j.​ejpe.​2019.​10.​003
24. Bentiss F, Jama C, Mernari B, Attari HE, Kadi LE, Lebrini M,
Traisnel M, Lagrenée M (2009) Corrosion control of mild steel
using 3,5-bis(4-methoxyphenyl)-4-amino-1,2,4-triazole in normal
hydrochloric acid medium. Corros Sci 51(8):1628–1635. https://​
doi.​org/​10.​1016/j.​corsci.​2009.​04.​009
25. Bouklah M, Benchat N, Aouniti A, Hammouti B, Benkaddour M,
Lagrenée M, Vezin H, Bentiss F (2004) Effect of the substitution
of an oxygen atom by sulphur in a pyridazinic molecule towards
inhibition of corrosion of steel in 0.5M ­H2SO4 medium. ProgOrgCoat 51(2):118–124. https://​doi.​org/​10.​1016/j.​porgc​oat.​2004.​06.​
005
26. Aribo S, Olusegun SJ, Ibhadiyi LJ, Oyetunji A, Folorunso DO
(2017) Green inhibitors for corrosion protection in acidizing oilfield environment. J Assoc Arab Univ Basic Appl Sci 24:34–38.
https://​doi.​org/​10.​1016/j.​jaubas.​2016.​08.​001
27. Umoren SA (2016) Polypropylene glycol: a novel corrosion
inhibitor for × 60 pipeline steel in 15% HCl solution. J Mol Liq
219:946–958. https://​doi.​org/​10.​1016/j.​molliq.​2016.​03.​077
28. Labjar N, Lebrini M, Bentiss F, Chihib N-E, Hajjaji SE, Jama
C (2010) Corrosion inhibition of carbon steel and antibacterial
properties of aminotris-(methylenephosphonic) acid. Mater Chem
Phys 119(1–2):330–336. https://​doi.​org/​10.​1016/j.​match​emphys.​
2009.​09.​006
29. Bouhlal F, Mazkour A, Labjar H, Benmessaoud M, SerghiniIdrissi M, El Mahi M, Lotfi EM, El Hajjaji S, Labjar N (2020)
Combination effect of hydro-alcoholic extract of spent coffee
grounds (HECG) and potassium Iodide (KI) on the C38 steel
corrosion inhibition in 1M HCl medium : experimental design
by response surface methodology. Chem Data Collect 29:100499.
https://​doi.​org/​10.​1016/j.​cdc.​2020.​100499
13
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
Page 11 of 11 78
Journal of Bio- and Tribo-Corrosion (2022) 8:78
30. Fiala A, Boukhedena W, Lemallem SE, Brahim Ladouani H,
Allal H (2019) Inhibition of carbon steel corrosion in HCl and
­H 2SO 4 solutions by ethyl 2-cyano-2-(1,3-dithian-2-ylidene)
acetate. J Bio- Tribo-Corros 5:42. https://​d oi.​o rg/​1 0.​1 007/​
s40735-​019-​0237-5
31. da Silva AB, D’Elia E, da Cunha Ponciano Gomes JA (2010) Carbon steel corrosion inhibition in hydrochloric acid solution using
a reduced Schiff base of ethylenediamine. Corros Sci 52(3):788–
793. https://​doi.​org/​10.​1016/j.​corsci.​2009.​10.​038
32. Solmaz R (2010) Investigation of the inhibition effect of 5-((E)4-phenylbuta-1,3-dienylideneamino)-1,3,4- thiadiazole-2-thiol
Schiff base on mild steel corrosion in hydrochloric acid. Corros
Sci 52(10):3321–3330. https://​doi.​org/​10.​1016/j.​corsci.​2010.​06.​
001
33. Lowmunkhong P, Ungthararak D, Sutthivaiyakit P (2010)
Tryptamine as a corrosion inhibitor of mild steel in hydrochloric
acid solution. Corros Sci 52(1):30–36. https://​doi.​org/​10.​1016/j.​
corsci.​2009.​08.​039
34. Aziate G, Yadini AE, Saufi H, Almaofari A, Benhmama A, Harhar
H, Gharby S, El Hajjaji S (2015) Study of jojoba vegetable oil as
inhibitor of carbon steel C38 corrosion in different acidic media.
J Mater Environ Sci 6:1877
35. Left DB, Zertoubi M, Irhzo A, Azzi M (2013) Revue: Huiles et
Extraits de plantes comme inhibiteurs de corrosion pour différents
métaux et alliages dans le milieu acide chlorhydrique. (Review:
Oils and extracts plants as corrosion inhibitors for different metals and alloys in hydrochloric acid medium). J Mater Environ Sci
4:855
36. Oguzie EE, Adindu CB, Enenebeaku CK, Ogukwe CE, Chidiebere
MA, Oguzie KL (2012) Natural products for materials protection:
mechanism of corrosion inhibition of mild steel by acid extracts
of piper guineense. J Phys Chem C 116(25):13603–13615. https://​
doi.​org/​10.​1021/​jp300​791s
37. Bouanis M, Tourabi M, Nyassi A, Zarrouk A, Jama C, Bentiss F (2016) Corrosion inhibition performance of 2,5-bis(4dimethylaminophenyl)-1,3,4-oxadiazole for carbon steel in HCl
solution: gravimetric, electrochemical, and XPS studies. Appl
Surf Sci 389:952–966. https://​doi.​org/​10.​1016/j.​apsusc.​2016.​07.​
115
38. Bentiss F, Mernari B, Traisnel M, Vezin H, Lagrenée M (2011) On
the relationship between corrosion inhibiting effect and molecular structure of 2,5-bis(n-pyridyl)-1,3,4-thiadiazole derivatives
in acidic media : Ac impedance and DFT studies. Corros Sci
53(1):487–495. https://​doi.​org/​10.​1016/j.​corsci.​2010.​09.​063
39. Bammou L, Belkhaouda M, Salghi R, Benali O, Zarrouk A,
Zarrok H, Hammouti B (2014) Corrosion inhibition of steel in sulfuric acidic solution by the Chenopodium ambrosioides Extracts.
J Assoc Arab Univ 16:83
40. El Hamdouni Y, Bouhlal F, Kouri H, Chellouli M, Benmessaoud M, Dahrouch A, Labjar N, El Hajjaji S (2020) Use of
omeprazole as inhibitor for C38 steel corrosion in 1.0 M H3PO4
medium. J Fail Anal Prev 20(2):563–571. https://d​ oi.o​ rg/1​ 0.1​ 007/​
s11668-​020-​00862-5
41. Hossam K, Bouhlal F, Hermouche L, Merimi I, Labjar H,
Chaouiki A, Labjar N, Malika S-I, Dahrouch A, Chellouli M,
Hammouti B, El Hajjaji S (2021) Understanding corrosion inhibition of C38 steel in HCl media by omeprazole: insights for experimental and computational studies. J Fail Anal Prev 21(1):213–
227. https://​doi.​org/​10.​1007/​s11668-​020-​01042-1
42. El Faydy M, Rbaaa M, Lakhrissi L, Lakhrissi B, Warad I, Zarrouk
A, Obot IB (2019) Corrosion protection of carbon steel by two
newly synthesized benzimidazol-2-ones substituted 8-hydroxyquinoline derivatives in 1 M HCl: experimental and theoretical study.
Surf Interfaces 14:222
43. Kissi M, Bouklah M, Hammouti B, Benkaddour M (2006) Establishment of equivalent circuits from electrochemical impedance
spectroscopy study of corrosion inhibition of steel by pyrazine
in sulphuric acidic solution. Appl Surf Sci 252(12):4190–4197.
https://​doi.​org/​10.​1016/j.​apsusc.​2005.​06.​035
44. Wang Q, Tan B, Bao H, Xie Y, Mou Y, Li P, Chen D, Shi Y, Li
X, Yang W (2019) Evaluation of Ficus tikoua leaves extract as an
eco-friendly corrosion inhibitor for carbon steel in HCl media.
Bioelectrochemistry 128:49–55. https://​doi.​org/​10.​1016/j.​bioel​
echem.​2019.​03.​001
45. Dahmani M, Et-Touhami A, Al-Deyab SS, Hammouti B, Bouyanzer A (2010) Corrosion inhibition of C38 steel in 1 M HCl : a
comparative study of black pepper extract and its isolated piperine. Int J Electrochem Sci 5:10
46. Manimegalai S, Manjula P (2015) Thermodynamic and adsorption
studies for corrosion inhibition of mild steel in aqueous media by
Sargasam swartzii (Brown algae). J Mater Environ Sci 6:1629
47. Ijuo GA, Orokpo MA, Surma N, Tor PN (2018) Methanol extract
of Canarium sweinfurthii as a green inhibitor for the corrosion of
mild steel in HCl: adsorption, kinetic, thermodynamic and synergistic studies. J Mater Environ Sci 9:3113
48. Damej M, Kaya S, EL Ibrahimi B, Lee H-S, Molhi A, Serdaroğlu
G, Benmessaoud M, Ali IH, EL Hajjaji S, Lgaz H (2021) The
corrosion inhibition and adsorption behavior of mercaptobenzimidazole and bis- mercaptobenzimidazole on carbon steel in 1.0
M HCl: experimental and computational insights. Surf Interfaces
24:101095. https://​doi.​org/​10.​1016/j.​surfin.​2021.​101095
49. Christmann K (2013) Introduction to surface physical chemistry, vol 1. Steinkopff, Heidelberg. https://​doi.​org/​10.​1007/​
978-3-​662-​08009-2
50. Berrissoul A, Loukili E, Mechbal N, Benhiba F, Guenbour A,
Dikici B, Zarrouk A, Dafali A (2020) Anticorrosion effect of a
green sustainable inhibitor on mild steel in hydrochloric acid. J
Colloid Interface Sci 580:740–752. https://​doi.​org/​10.​1016/j.​jcis.​
2020.​07.​073
51. da Rocha JC, da Cunha Ponciano Gomes JA, D’Elia E (2010)
Corrosion inhibition of carbon steel in hydrochloric acid solution
by fruit peel aqueous extracts. Corros Sci 52:2341–2348. https://​
doi.​org/​10.​1016/j.​corsci.​2010.​03.​033
52. Solmaz R, Kardaş G, Yazıcı B, Erbil M (2008) Adsorption and
corrosion inhibitive properties of 2-amino- 5-mercapto-1,3,4thiadiazole on mild steel in hydrochloric acid media. Colloids
Surf Physicochem Eng Asp 312:7–17. https://​doi.​org/​10.​1016/j.​
colsu​rfa.​2007.​06.​035
53. Znini M, Majidi L, Laghchimi A, Paolini J, Hammouti B, Costa
J, Bouyanzer A, Al-Deyab SS (2011) Chemical composition and
anticorrosive activity of Warionia Saharea essential oil against the
corrosion of mild steel In 0.5. Int J Electrochem Sci 6:16
54. Fouda SA (2019) Corrosion inhibition effect of methanol extract
of nerium oleander on copper in nitric acid solutions. Int J Electrochem Sci. https://​doi.​org/​10.​20964/​2019.​07.​31
55. Constantin F (s. d.) Etude de l’efficacité d’inhibiteurs de corrosion
utilisés dans les liquides de refroidissement. 175.
56. Oguzie EE, Njoku VO, Enenebeaku CK, Akalezi CO, Obi C
(2008) Effect of hexamethylpararosaniline chloride (crystal violet)
on mild steel corrosion in acidic media. Corros Sci 50(12):3480–
3486. https://​doi.​org/​10.​1016/j.​corsci.​2008.​09.​017
Publisher's Note Springer Nature remains neutral with regard to
jurisdictional claims in published maps and institutional affiliations.
13
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
Terms and Conditions
Springer Nature journal content, brought to you courtesy of Springer Nature Customer Service Center GmbH (“Springer Nature”).
Springer Nature supports a reasonable amount of sharing of research papers by authors, subscribers and authorised users (“Users”), for smallscale personal, non-commercial use provided that all copyright, trade and service marks and other proprietary notices are maintained. By
accessing, sharing, receiving or otherwise using the Springer Nature journal content you agree to these terms of use (“Terms”). For these
purposes, Springer Nature considers academic use (by researchers and students) to be non-commercial.
These Terms are supplementary and will apply in addition to any applicable website terms and conditions, a relevant site licence or a personal
subscription. These Terms will prevail over any conflict or ambiguity with regards to the relevant terms, a site licence or a personal subscription
(to the extent of the conflict or ambiguity only). For Creative Commons-licensed articles, the terms of the Creative Commons license used will
apply.
We collect and use personal data to provide access to the Springer Nature journal content. We may also use these personal data internally within
ResearchGate and Springer Nature and as agreed share it, in an anonymised way, for purposes of tracking, analysis and reporting. We will not
otherwise disclose your personal data outside the ResearchGate or the Springer Nature group of companies unless we have your permission as
detailed in the Privacy Policy.
While Users may use the Springer Nature journal content for small scale, personal non-commercial use, it is important to note that Users may
not:
1. use such content for the purpose of providing other users with access on a regular or large scale basis or as a means to circumvent access
control;
2. use such content where to do so would be considered a criminal or statutory offence in any jurisdiction, or gives rise to civil liability, or is
otherwise unlawful;
3. falsely or misleadingly imply or suggest endorsement, approval , sponsorship, or association unless explicitly agreed to by Springer Nature in
writing;
4. use bots or other automated methods to access the content or redirect messages
5. override any security feature or exclusionary protocol; or
6. share the content in order to create substitute for Springer Nature products or services or a systematic database of Springer Nature journal
content.
In line with the restriction against commercial use, Springer Nature does not permit the creation of a product or service that creates revenue,
royalties, rent or income from our content or its inclusion as part of a paid for service or for other commercial gain. Springer Nature journal
content cannot be used for inter-library loans and librarians may not upload Springer Nature journal content on a large scale into their, or any
other, institutional repository.
These terms of use are reviewed regularly and may be amended at any time. Springer Nature is not obligated to publish any information or
content on this website and may remove it or features or functionality at our sole discretion, at any time with or without notice. Springer Nature
may revoke this licence to you at any time and remove access to any copies of the Springer Nature journal content which have been saved.
To the fullest extent permitted by law, Springer Nature makes no warranties, representations or guarantees to Users, either express or implied
with respect to the Springer nature journal content and all parties disclaim and waive any implied warranties or warranties imposed by law,
including merchantability or fitness for any particular purpose.
Please note that these rights do not automatically extend to content, data or other material published by Springer Nature that may be licensed
from third parties.
If you would like to use or distribute our Springer Nature journal content to a wider audience or on a regular basis or in any other manner not
expressly permitted by these Terms, please contact Springer Nature at
onlineservice@springernature.com