Experimental and theoretical study on triazole derivatives as chelating agents to remove Fe++ Ions from wastewater in oil field

Article abstract of DOI:10.1002/jhet.3976

In this study, we synthesized triazole derivatives as chelating agents (3-(p-methylphenyl)-5-(phenylsulfonyl)-4H-1,2,4-triazoline (MT), 3-phenyl-5-(phenylsulfonyl)-4H-1,2,4-triazoline (PT), and 3-(p-fluorophenyl)-5-(phenylsulfonyl)-4H-1,2,4-triazoline (FT) to remove Fe⁺⁺ ions from wastewater in oil field. The effect of synthesized compounds on the removal of iron (II) from iron-contaminated samples (Lab. design) and an industrial wastewater sample studied using DR5000 UV-vis spectrophotometer technique. Removal of iron was studied at different concentrations of FeSO₄ solution and field sample concentration. In addition, removal of iron (II) was investigated at different times. The performance of the derivative groups (methyl and fluoro) on chelating of Fe⁺⁺ ions was studied. The prepared compounds show high efficiency in removing the iron ions from the water samples used. The removal efficiency of the title molecules (MT), (PT), and (FT) was investigated using DMol3 (Materials Studio v7.0) based on quantum descriptors such as E_HOMO and E_LUMO. Mulliken atomic charges distribution and Fukui indices were estimated to verify the local reactive sites of the molecules. The quantum chemical parameters were found to suitable to interpret the performance of the investigated molecules as a chelating agent for Fe⁺⁺.

Full text of DOI:10.1002/jhet.3976

Received: 28 January 2020
DOI: 10.1002/jhet.3976
Revised: 2 March 2020
Accepted: 12 March 2020
A R T I C L E
Experimental and theoretical study on triazole derivatives
as chelating agents to remove Fe++ Ions from wastewater
in oil field
Eid M. S. Azzam1,2
| Elshafie A. M. Gad2 | Jabir H. Al-Fahemi3
1Chemistry Department, College of
Abstract
Sciences, University of Hail, Hail, KSA
2Petrochemicals Department, Egyptian
Petroleum Research Institute, Cairo,
Egypt
3Chemistry Department, Faculty of
Applied Sciences, Umm Al-Qura
University, Makkah, Saudi Arabia
In this study, we synthesized triazole derivatives as chelating agents
(3-(p-methylphenyl)-5-(phenylsulfonyl)-4H-1,2,4-triazoline (MT), 3-phenyl-5-
(phenylsulfonyl)-4H-1,2,4-triazoline
(PT),
and
3-(p-fluorophenyl)-5-
(phenylsulfonyl)-4H-1,2,4-triazoline (FT) to remove Fe++ ions from wastewater
in oil field. The effect of synthesized compounds on the removal of iron (II) from
iron-contaminated samples (Lab. design) and an industrial wastewater sample
studied using DR5000 UV-vis spectrophotometer technique. Removal of iron was
studied at different concentrations of FeSO4 solution and field sample concentra-
tion. In addition, removal of iron (II) was investigated at different times. The per-
formance of the derivative groups (methyl and fluoro) on chelating of Fe++ ions
was studied. The prepared compounds show high efficiency in removing the iron
ions from the water samples used. The removal efficiency of the title molecules
(MT), (PT), and (FT) was investigated using DMol3 (Materials Studio v7.0) based
on quantum descriptors such as EHOMO and ELUMO. Mulliken atomic charges dis-
tribution and Fukui indices were estimated to verify the local reactive sites of the
molecules. The quantum chemical parameters were found to suitable to interpret
Correspondence
Eid M. S. Azzam. Chemistry Department,
College of Sciences, University of Hail,
Hail, KSA
Email: eazzamep@yahoo.com
the performance of the investigated molecules as a chelating agent for Fe++
.
1 | INTRODUCTION
are synthesized and applied for the removal of heavy metals.
The copolymer containing triazole rings with galactose resi-
due showed good results as a resin for the cleaning of water
contaminated with mercury.[5] Triazoles and their deriva-
tives are a very important class of heterocyclic compounds.
Triazole derivatives are biologically active compounds,[6–11]
corrosion inhibitors,[12] dyes,[13] acid-base indicators,[14] and
other industrial chemicals.[15]Triazoles have been used as
organic chelators, chelating excessive iron. The high con-
centations of iron in blood is very toxic, so it should be
maintained in its normal levels. For this, bis-hydroxyphenyl-
triazoles have been used as an effective chelator.[16,17]
Heavy metals constitute a very heterogeneous group of ele-
ments widely varied in their chemical properties and biologi-
cal functions. Heavy metals are categorized under
environmental pollutants due to their toxic effects on plants,
animals, and human beings.[1] Removal of toxic heavy
metals such as lead, cadmium, and copper is one of the
main problems in wastewater treatment.[2] These metals can
enter water systems through industrial mining, gal-
vanoplastic foundries, and pipe corrosion. Long-term expo-
sure to these heavy metals can accumulate in living
organisms, causing several disorders and serious diseases.[3,4]
Recently triazoles have been used in the removal of heavy
metals, where new copolymers with triazole pendant groups
The main target of this work is the use of the synthe-
sized triazole derivatives as chelating agents to remove
Fe++ ions from wastewater in the oil field. In addition,
J Heterocyclic Chem. 2020;1–11.
wileyonlinelibrary.com/journal/jhet
© 2020 Wiley Periodicals, Inc.
1

2
AZZAM ET AL.
we target the chelation of the synthesized triazole deriva-
tives with Fe++ ions using computational methodology.
Schuchard, Germany) with thiosemicarbazide (7.3 g, 0.1 mol/L)
(98%, Loba Chemie, India) in 50 mL of ethyl alcohol (98%,
Biochem, Egypt) and refluxed for 6 hours. The solvent of
crystallization was ethyl alcohol, and the yield was white
crystals. The melting point of this compound was 160-165ꢀC.[5]
2 | MATERIALS AND
EXPERIMENTAL TECHNIQUES
2.1 | Materials
2.1.2 | Synthesis of 3-(p-methylphenyl)-
5-(phenylsulfonyl)-4H–1,2,4-triazoline
(MT); 3-phenyl-5-(phenylsulfonyl)-4H-
1,2,4-triazole (PT); and 3-(p-fluorophenyl)-
5-(phenylsulfonyl)-4H-1,2,4-triazole (FT)
2.1.1 | Synthesis of p-methyl
benzaldehyde thiosemicarbazones
The investigated compounds were synthesized as shown in
scheme 1 by reacting para methyl benzaldehyde, benzalde-
hyde, and p-fluoro-benzaldehyde (10 g, 0.1 mol/L) (98%,
The compounds 3-(p-methylphenyl)-5-(phenylsulfonyl)-
4H–1,2,4-triazoline (MT); 3-phenyl-5- (phenylsulfonyl)
SCHEME 1 Synthesis of
triazole derivatives (PT, FT and
MT) compounds

AZZAM ET AL.
3
-4H-1,2,4-triazole
(PT);
and
3-(p-fluorophenyl)-5
(4.5 mL, 0.1 mol/L) each in the presence of potassium
carbonate anhydrous (3.5 g, 0.1 mol/L) in 10 mL dry
acetone (98%) and stirring for 24 hours and then
pouring over ice, filtration, and crystallization from
ethyl alcohol and gently dropping water. Melting
points were 95ꢀC-100ꢀC, and the yield was yellow crys-
tals (see Scheme 1).[5]
-(phenylsulfonyl)-4H-1,2,4-triazole (FT) were synthesized
by reacting p-methyl benzaldehyde thiosemicar-
bazone, para-methyl benzaldehyde thiosemicarbazone,
and benzaldehyde thiosemicarbazone, which were
synthesized as described in Section 2.1.1. (5 g, 0.1 mol/
L), respectively, with benzene sulfonyl chloride
SCHEME 2 Fragmentation
mechanism of the synthesized triazole
derivatives (PT, FT and MT)

4
AZZAM ET AL.
2.1.3 | Preparation of the heavy metal
solutions
detected for iron concentration using the DR5000 appa-
ratus after each period.[5]
In this study, depending on two ways for obtaining the
heavy metal solution, one practical method by preparing
different concentrations of a salt containing heavy metals
like iron. Ferrous sulfate was used. We prepared three
different concentrations of ferrous sulfate solution: 0.05,
0.15, and 0.5 mol/L. In the other way, we obtained a field
sample of “oil and gas,” containing a very high concen-
tration of iron. Each detected for the determination of
iron concentration using the DR5000 apparatus.[5]
2.2 | Experimental techniques
2.2.1 | Infrared spectrometer
All spectra were recorded with 2 cm−1 resolution at an
angle of incidence 80o relative to the surface normal
using BSU_MIR_ATR.xpm spectrophotometer.
2.2.2 | Proton nuclear magnetic
2.1.4 | Removal of the heavy metal from
prepared solutions and field samples using
synthesized triazole compounds
resonance (1HNMR)
1HNMR measurements performed on
instrument.
a
BRUKER
In this step; 2 mL of each compounds' solutions (MT,
PT, and FT) were added to 20 mL of each of ferrous sul-
fate concentrations (0.05, 0.15, and 0.5 mol/L). In addi-
tion, 2 mL of each compound was added to the field
sample. All these samples were stirred for different
periods, 30 minutes, 3 hour, and overnight. Each was
2.2.3 | Atomic mass spectrometer
Mass measurements were done using mass spectrometer
MSD 5975, using ion source/electron impact, its scale
50-1200 g/mole.
TABLE 1
Removal of Fe++ from prepared FeSO4 solutions
using MT compound
2.2.4 | Detection of iron (II)
concentrations
Fe2So4 solutions
0.05 M
0.15 M
0.5 M
Fe++ concentration
in blank solution
Fe++ concentration
after addition of MT
compound (0.1 M)
5 mg/L
14 mg/L
39 mg/L
The detection of Fe++ ions carried out using the DR5000 UV-
vis spectrophotometer, HACH Company, Germany. Only
2 mL of the stirred sample added to 100 mL of deionized
water, then shaking it to reach a proper mixing. Ten millili-
ters of the diluted sample was filled in each of DR5000's two
covets; the indicator was put in one of them and mixed. The
covet free of the indicator was used for zeroing the apparatus
then taking the reading of the other one then multiplying its
After 30 min
1 mg/L
9 mg/L
34 mg/L
32 mg/L
32 mg/L
After 3 h
1 mg/L
8 mg/L
8 mg/L
Overnight
1 mg/L
TABLE 2
Removal of Fe++ from prepared FeSO4 solutions
TABLE 3
Removal of Fe++ from prepared FeSO4 solutions
using FT compound
using PT compound
Fe2So4 solutions
0.05 M
0.15 M
0.5 M
Fe2So4 solutions
0.05 M
0.15 M
0.5 M
Fe++ concentration
in blank solution
5 mg/L
14 mg/L
39 mg/L
Fe++ concentration
in blank solution
5 mg/L
14 mg/L
39 mg/L
Fe++ concentration
after addition of FT
compound (0.1 M)
After 30 min
Fe++ concentration
after addition of PT
compound (0.1 M)
After 30 min
4 mg/L
14 mg/L
37 mg/L
36 mg/L
36 mg/L
3 mg/L
11 mg/L
36 mg/L
34 mg/L
34 mg/L
After 3 h
4 mg/L
After 3 h
4 mg/L
14 mg/L
12 mg/L
10 mg/L
10 mg/L
Overnight
4 mg/L
Overnight
3 mg/L

AZZAM ET AL.
5
reading by 100 due to the previous dilution. The dilution
made to match the scale of the apparatus.[5]
(A)
40
PT compound
30 min
35
30
25
20
15
10
5
after3hrs
overnight
Blank
3 | RESULTS AND DISCUSSION
3.1 | Chemical structure confirmation of
the synthesized triazole compounds (MT,
PT, and FT)
FTIR of the synthesized compounds showed peaks as
0
follows:
3-(p-methylphenyl)-5-(phenylsulfonyl)-4H-1,-
0.0
0.1
0.2
0.3
0.4
0.5
0.5
0.5
2,4-triazoline (MT) showed; N-H stretch at 3366.954 cm−1,
CH aromatic stretching at 3089.894 cm−1,C C aromatic
stretching showed three bands 1455.62, 1518.141, and
1573.024 cm−1, N-H bend at 1606.493 cm−1, and S O at
1082.348. 3-(p-fluorophenyl)-5-(phenylsulfonyl)-4H -1,-
2,4-triazoline (FT) showed; N-H stretch at 3333.98 cm−1, C N
stretch at 1647.2 cm−1, C C aromatic showed 2 stretching
bands at 1499.3 and 1606.553 cm−1, S O stretching at
1025.371 cm−1 and CH bending for para-substitution at
FeSO4 concentation (mol/l)
(B)
40
FT compound
30 min
35
30
25
20
15
10
5
after 3 hrs
overnight
Blank
830.213 cm−1.
3-phenyl-5–(phenylsulfonyl)-4H-1,2,4-
triazoline (PT) showed; N-H stretch at 3066.307 cm−1, N-H
bend at 1586.745 cm−1, C C aromatic stretching showed two
bands at 1445.84 and 1486.1 and S O at 1086.307 cm−1 CH
aromatic monosubstitution showed two stretching bands at
683.650 and 721.581 cm−1. The synthesized compounds
0
0.0
0.1
0.2
0.3
0.4
FeSO4 concentation (mol/l)
1
showed HNMR spectra with peaks as follows: 3-(p-methyl)
(C)
phenyl-5–(phenylsulfonyl)-4H-1,2,4-triazoline (MT) showed
peaks at σ = 1.2(s, 3H, CH3), 7.2-7.8 (m, 4H, aromatic),
7.9-8.288 (m, 5H, aromatic), 8.3 (s, 1H, NH), 8.4 (s, 1H, NH).
3-(p-fluorophenyl)-5–(phenylsulfonyl)-4H-1,2,4-triazoline
(FT) showed peaks at σ = 7.3-7.78 (m, 4H, aromatic),
8-8.571 (m, 5H, aromatic), 12 (s, 1H, NH). 3-phenyl-5–
(phenylsulfonyl)-4H -1,2,4-triazoline (PT) showed peaks
at σ = 7.46-7.8 (m, 5H, aromatic), 7.9-8.288 (m, 5H, aro-
matic), 8.3 (s, 1H, NH). The mass spectra of the synthe-
sized compounds showed peaks as follows:
40
35
30
25
20
15
10
5
MT compound
30 min
after3hrs
overnight
Blank
3-(p-methyl)
phenyl-5–(phenylsulfonyl)-4H-1,2,4-
0
triazoline (MT) showed peaks at 299, 158, 118, and 77 m/z.
3-(p-fluorophenyl)-5–(phenylsulfonyl)-4H-1,2,4-triazoline
(FT) showed peaks at 303, 162, 121, and 77 m/z. 3-phenyl-
5–(phenylsulfonyl)-4H-1,2,4-triazoline (PT) showed peaks at
285, 118, 90, and 77 m/z. The mechanism of fragmentation
shows in Scheme 2.
0.0
0.1
0.2
0.3
0.4
FeSO4 concentation (mol/l)
FIGURE 1 Removal of Fe++ using the synthesized compounds
PT A, FT B, and MT C [Color figure can be viewed at
wileyonlinelibrary.com]
TABLE 4
Removal of Fe++ ions from oil field sample using the most powerful remover (MT compound)
Solutions
Fe++ ions concentration
Blank (standard solutions without any additions)
After addition of compound MT (0.1 M)
321 mg/L
After 30 min
After 3 h
282 mg/L
After 12 h
After 24 h
285 mg/L
200 mg/L
160 mg/L

6
AZZAM ET AL.
3.2 | Removal of Fe++ ions from the
prepared FeSO4 solutions
was prepared in lab by dissolving ferrous sulfate in
deionized water making stock solutions of different
concentrations; 0.05, 0.15, and 0.5 M. As well as taking
a field sample of produced water, which is the indus-
trial wastewater, separated from crude oil in process
facilities “containing a very high concentration of dis-
solved Fe++ ions.” The effect of the synthesized com-
pounds studied on different stirring periods. DR-5000
spectrophotometer was used to measure the Fe++ ions
concentration after stirring. The results were compared
between the effects of the synthesized compounds on
the removal of dissolved Fe++ ions on the samples,
which prepared in the lab and the most powerful
remover was applied on the field sample.
The synthesized compounds (MT, FT, and PT) with
the same concentrations (0.1 M) added respectively to
the prepared samples and left for stirring and the con-
centration of Fe++ ions measured on different periods
of stirring 30 minutes, 3 hour, and overnight. The
results represented in Tables 1-3 and Figure 1A-C. The
results show that the activity of the synthesized com-
pounds MT, FT, and PT toward the removal of Fe++
ions from the solution which may be related to the
covalent bond formation between the lone pair elec-
tron of nitrogen atoms and the positive charge of Fe++
ions. It was noticed from the results in Tables 1-3 and
In this section, the effect of synthesized compounds
(MT, FT, and PT) on the removal of Fe++ ions was stud-
ied on water samples containing dissolved iron, which
340
320
300
280
260
240
220
200
180
160
140
0 min
30 min
3hrs
12 hrs
24 hrs
Time
FIGURE 2 Removal of Fe++ from the oil field sample using
the most powerful remover (MT compound)
MT
PT
FT
Hydrogen; white, Carbon; grey, Nitrogen; blue, Oxygen; red, Sulfur; Yellow,
Fluorine; pale blue
FIGURE 3 Triazole derivatives (MT, PT, and FT), Colors; red, blue, gray and white for oxygen, nitrogen, carbon, and hydrogen, respectively
[Color figure can be viewed at wileyonlinelibrary.com]

AZZAM ET AL.
7
Figure 1A-C, that the concentration of Fe++ ions
decrease with the time increase from 30 minutes to
overnight. The reason for this may be attributed to the
chelating of Fe++ ions by the NH group in the
synthesized compounds (MT, FT, and PT).[5] The
results for the removal of Fe++ ions from the oil field
sample are represented in Table 4 and Figure 2. Fe++
decreased from 321 mg/L in the blank sample to
TABLE 5
Quantum chemical parameters of triazole derivatives
MT
PT
FT
High occupied molecular orbital (eV)
Low unoccupied molecular orbital (eV)
Energy gap (eV)
EHOMO
−0.22224
−0.14176
0.08049
0.22224
0.14176
0.18200
0.16097
6.21226
0.00267
−0.22890
−0.14564
0.08326
0.22890
0.14564
0.18727
0.16651
6.00550
0.00292
−0.22902
−0.14688
0.08214
0.22902
0.14688
0.18795
0.16428
6.08724
0.00290
ELUMO
DE Gap = ELUMO - EHOMO
I= EHOMO
A= ELUMO
X = (I+A)/2
h = (I−A)/2
S = 1/h
Ionization potential (eV)
Electron affinity (eV)
Absolute electronegativity
Global hardness (eV)
Global softness (eV)−1
Global electrophilicity index (eV)
w = m2/2h
where m = −X
Back-donation energy (eV)
DEBack-donation = h/4
0.04024
5.08785
0.04163
4.90268
0.04107
4.96735
XFe + xinh
The fraction of electron transferred
DN = 2ðη
Fe + ηinhÞ
HOMO
LUMO
MT
PT
FT
FIGURE 4 Graphical representation of FMO of triazole derivatives (MT, PT, and FT) [Color figure can be viewed at wileyonlinelibrary.com]

8
AZZAM ET AL.
160 mg/L after 24 hour with the addition of 0.1 M of
MT compound. These results indicate the ability of MT
compound for removal of Fe++ ions from the oil field
sample.
energy gap ΔE, Global hardness η, global softness S, ioniza-
tion potential I, electron affinity A, absolute electronegativity
X, global electrophilicity index ω, the back donation ΔEBack-
donation, were calculated on the basis of EHOMO and ELUMO
.
Further investigation about the chelation between the
synthesized compounds and Fe++ ions will discuss using
the computational methodology as follows.
Quantum chemical parameters calculated using equa-
tions represented in previous studies[18–21]: I, A, χ and η can
be determined based on EHOMO and the ELUMO. As well as,
Fukui indices (f+ and f−), which represent local nucleo-
philic and electrophilic attacks from DMol3 calculation.
3.3 | Computational methodology
Triazole derivatives structures namely, (3-(4-met-
3.3.1 | Theoretical studies
hylphenyl)-5-(phenylsulfonyl)-4H-1,2,4-triazole
(MT),
3-phenyl-5-(phenylsulfonyl)-4H-1,2,4-triazole (PT), and
3-(4-fluorophenyl)-5-(phenyl-sulfonyl) -4H-1,2,4-triazole
(FT) can be illustrated in (Figure 3). Geometry optimization
on this molecule was applied using DMol3 calculation model
included in Materials Studio v7.0. Electronic parameters
were; restricted spin polarization, zero charge, functional
pwc. All electrons in core treatment are considered DNP
Basis set.” Both EHOMO and ELUMO were calculated as listed
in Table 5 and graphically represented in Figure 4. The
Frontier molecule orbital density (FMO)[5,22] distribu-
tions of triazole derivatives represented in Figure 4. The
electron density of EHOMO distributed over triazole and
the phenyl connected directly to triazole moiety. The
EHOMO and ELUMO values listed in Table 5. EHOMO is dis-
tributed over atoms; N7, N8, N6, N5, O2, and O3.
According to the obtained values in Table 5, as EHOMO
value increases, the ease of electron donation occurs.
TABLE 6
Mulliken atomic charges
PT
MT
FT
S (1)
0.390
−0.435
−0.402
0.302
S (1)
0.392
−0.426
−0.409
0.284
S (1)
0.416
−0.414
−0.414
0.344
O (2)
O (3)
C (4)
O (2)
O (2)
O (3)
C (4)
MT
O (3)
C (4)
N (5)
N (6)
N (7)
C (8)
−0.436
−0.183
−0.238
0.319
N (5)
N (6)
N (7)
C (8)
−0.437
−0.188
−0.244
0.313
N (5)
N 6)
−0.444
−0.276
−0.228
0.319
N (7)
C (8)
C (9)
0.002
C (9)
−0.004
−0.084
−0.091
−0.126
−0.128
−0.120
−0.016
−0.133
−0.115
−0.129
−0.131
0.001
C (9)
−0.016
−0.088
−0.103
−0.127
−0.125
−0.119
−0.011
−0.113
−0.130
−0.144
−0.142
0.299
PT
FT
C (10)
C (11)
C (12)
C (13)
C (14)
C (15)
C (16)
C (17)
C (18)
C (19)
C (20)
−0.082
−0.091
−0.123
−0.124
−0.116
−0.009
−0.134
−0.117
−0.121
−0.123
−0.127
C (10)
C (11)
C (12)
C (13)
C (14)
C (15)
C (16)
C (17)
C (18)
C (19)
C (20)
C (21)
C (10)
C (11)
C (12)
C (13)
C (14)
C (15)
C (16)
C (17)
C (18)
C (19)
C (20)
F (21)
−0.373
0.392
−0.316
0.416
FIGURE 5 Molecular electrostatic potential (MEP) of the
triazole derivatives (MT, PT, and FT) [Color figure can be viewed at
wileyonlinelibrary.com]
Max.
Min.
0.390
−0.436
−0.446
−0.444

AZZAM ET AL.
9
f+
f-
MT
PT
FT
FIGURE 6 Graphical representation of Fukui functions (f+ and f-) of triazole derivatives (MT, PT, and FT) [Color figure can be viewed
at wileyonlinelibrary.com]
TABLE 7
Fukui function values
PT
MT
FT
(f+ and f−) for the investigated
molecules
f+
0.038
f−
0.029
f+
0.037
f−
0.019
f+
0.033
f−
0.065
S (1)
S (1)
O (2)
S (1)
O (2)
O (3)
0.070
0.075
0.030
0.029
0.062
0.046
0.046
−0.005
0.021
0.017
0.016
0.015
0.036
0.000
0.024
0.022
0.013
0.016
0.035
0.083
0.110
0.041
0.009
0.053
0.062
0.040
−0.007
0.006
0.007
0.015
0.015
0.023
0.012
0.021
0.026
0.020
0.018
0.038
0.071
0.076
0.031
0.027
0.065
0.045
0.047
−0.002
0.021
0.018
0.016
0.016
0.037
−0.004
0.020
0.019
0.015
0.017
0.023
−0.007
0.076
0.065
0.093
0.048
0.011
0.054
0.061
0.035
−0.008
0.005
0.006
0.013
0.013
0.021
0.019
0.022
0.026
0.027
0.024
0.030
−0.008
0.093
O (2)
O (3)
0.075
0.075
0.042
0.037
0.050
0.049
0.048
−0.004
0.017
0.003
0.014
0.014
0.025
0.004
0.026
0.030
0.023
0.019
0.047
0.044
0.075
0.159
0.159
−0.004
0.005
0.038
0.048
0.036
−0.014
0.011
0.018
0.019
0.018
0.030
−0.003
0.015
0.013
0.016
0.016
0.029
0.033
0.159
O (3)
C (4)
C (4)
C (4)
N (5)
N (5)
N (5)
N (6)
N (7)
N (6)
N (7)
N (6)
N (7)
C (8)
C (8)
C (8)
C (9)
C (9)
C (9)
C (10)
C (11)
C (12)
C (13)
C (14)
C (15)
C (16)
C (17)
C (18)
C (19)
C (20)
C (10)
C (11)
C (12)
C (13)
C (14)
C (15)
C (16)
C (17)
C (18)
C (19)
C (20)
C (21)
C (10)
C (11)
C (12)
C (13)
C (14)
C (15)
C (16)
C (17)
C (18)
C (19)
C (20)
F (21)
0.075
0.110

10
AZZAM ET AL.
Molecular Formula:
Structure
[C15H15N3O2S]Fe++
[C15H15N3O2S]2Fe++
[C15H15N3O2S]3Fe++
[C15H15N3O2S]4Fe++
Hydrogen; white, Carbon; grey, Nitrogen; blue, Oxygen; red, Sulfur; Yellow,
Fluorine; pale blue, Iron; green
FIGURE 7 The probable chelating structure of triazole derivative (MT) with Fe++ [Color figure can be viewed at
wileyonlinelibrary.com]
Energy gap (eV) values indicate that triazole derivative
(MT) is more reactive than the other derivatives (PT) and
(FT). Smaller values of ionization potential (I) and global
hardness (h) indicate the ease of electron donation, as
the higher value of global softness does.
Electron transfer ΔN happens as an electron exchange
from an atom or a molecule to transition metal complex.
The electronic flow occurs from lower electronegativity
organic inhibitors to a higher value of iron. So, the ΔN
from investigated molecules was estimated. In this study,
the electronegativity of bulk iron was used xFe = 1.83 eV
based on the Pauling scale and a global hardness of ηFe = 0,
by assuming that for a metallic bulk I = A, the fraction of
electron transferred order is MT > PT > FT.
liability to nucleophilic attack. It is evident that red cites
are responsible for the nucleophilic f+. Electron density
localized over triazole atoms; N7, N8, N6, and N5 as well
as the oxygen atoms O2 and O3; however, the blue cites
accounted for electrophilic f- attack. The obtained Fukui
function values (f+ and f-) for the investigated molecules
shown in Table 7, indicate that N (6) atoms have higher
values for f+ that are susceptible to the nucleophilic
attack. Accordingly, illustration for the chelating proba-
bility of Fe++ with the studied molecules represented in
Figure 7. From the above results it is clear that the effi-
ciency of the synthesized compunds for removal of Fe++
ions can be considered MT > PT > FT.
Mulliken atomic charges distribution as obtained
from the analysis of DMol3 listed in Table 6. It is
observed that sulfur S(1) atoms have positive charges;
The most negative nitrogen N(5).
4 | CONCLUSION
The removal of Fe++ ions from wastewater in oil field using
(3-(p-methylphenyl)-5-(phenylsulfonyl)-4H-1,2,4-triazoline
(MT), 3-phenyl-5-(phenylsulfonyl)-4H-1,2,4-triazoline
(PT), and 3-(p-fluorophenyl)-5-(phenylsulfonyl)-4H-
1,2,4-triazoline (FT) was studied.
We used DMol3 (Materials Studio v7.0) based on
quantum descriptors to investigate the removal efficiency
of the title molecules (MT), (PT), and (FT). The quantum
chemical parameters confirmed the chelation of Fe++
using the synthesized compounds.
Molecular electrostatic potential (MEP) can confirm
the reactive centers of a wide variety of chemical systems
in both electrophilic and nucleophilic reactions.[23] The
MEP for the triazole derivatives shown in Figure 5 Red
area has an electron. The blue region is localized over N
(6) indicating a possible atom for nucleophilic attack.
The results also prove that the susceptibility of chelation
of Fe++ can occur by N (6). Condensed Fukui func-
tions[5,19] shown in Figure 6 give an illustration of the
reactive sites in each triazole derivative molecule. The f-
Fukui function that reflects susceptibility to electrophilic
attack. in addition, f+ Fukui function, that reflects
ORCID
Eid M. S. Azzam https://orcid.org/0000-0003-3696-9596

AZZAM ET AL.
11
[16] C. Hershko, A. M. Konijn, H. P. Nick, W. Breuer,
Z. I. Cabantchik, G. Link, Blood 2001, 97, 1115.
[17] E. Nishbet-Brown, N. F. Oliviei, P. J. Giardina, in 44th Annual
ASH Meeting, Abstract No. 3111, Philadelphia, PA 2002.
[18] K. M. Zohdy, A. M. El-Shamy, A. Kalmouch, E. A. M. Gad,
Egypt. J. Pet. 2019, 28, 355.
[19] E. A. M. Gad, E. M. S. Azzam, S. Abdel Halim, Egypt. J. Pet.
2018, 27, 695.
[20] J. H. Al-Fahemi, M. Abdallah, E. A. M. Gad, B. A.
A. L. Jahdaly, J. Mol. Liq. 2016, 222, 1157.
[21] E. A. M. Gad, J. H. Al-Fahemi, Int. J. Sci. Eng. Res 2015, 6, 570.
[22] M. Sikine, H. Elmsellem, Y. Kandri Rodi, Y. Kadmi,
M. Belghiti, H. Steli, Y. Ouzidan, N. K. Sebbar, E. M. Essassi,
J. Mater. Environ. Sci 2017, 8, 116.
[23] C. Y. Panicker, H. T. Varghese, P. S. Manjula, B. K. Sarojini,
B. Narayana, J. A. War, S. K. Srivastava, C. V. Alsenoy,
A. A. Al-Saadi, Spectrochim. Acta, Part A 2015, 151, 198.
REFERENCES
[1] T. R. Rajeswari, N. Sailaja, J. Chem. Pharm. Sci. 2014, 181, 175.
[2] A. M. Elbedwehy, A. M. Abou-Elanwar, A. O. Ezzat,
A. M. Atta, Polymer 2019, 11, 1938.
[3] A. Hazrat, K. Ezzat, I. Ikram, J. Chem. 2019, 2019.
[4] C. F. Carolin, P. S. Kumar, A. Saravanan, G. J. Joshiba,
M. Naushad, J. Environ. Chem. Eng 2017, 5, 2782.
[5] E. M. S. Azzam, S. A. Ahmed, H. H. Mohamed, M. A. Adly,
E. A. M. Gad, Desalin. Water Treat. 2018, 1.
[6] F. A. Hassan, K. W. Younus, Res. J. Biol. Sci. 2012, 7, 48.
[7] S. P. Pardeshi, S. V. Patil, R. Patil, V. D. Bobade, J. Chem.
Pharm. Res. 2014, 6, 675.
[8] A. J. K. Atia, S. S. Al-Mufrgeiy, Am. J. Chem. 2012, 2, 150.
[9] T. Taj, R. R. Kamble, T. Gireesh, B. V. Badami, J. Chem. Sci.
2011, 123, 657.
[10] O. Bekircan, E. Mentes¸e, S. Ülker, C. Kucuk, Arch. Pharm.
Chem. Life Sci. 2014, 347, 387.
[11] H. M. Abdullah, I. K. Jassim, M. N. Safi, Kerbala J. Pharm. Sci.
2012, 4, 115.
[12] S. Sripriya, C. Subha, A. Selvaraj, IOSR J. Appl. Chem. 2013,
6, 25.
[13] J. C. Er, M. K. Tang, C. G. Chia, H. Liew, M. Vendrell,
Y. T. Chang, J. Chem. Sci. 2014, 4, 2168.
[14] V. N. Bulut, C. Duran, A. Gundogdu, M. Soylak, N. Yildirim,
M. Tufekci, Bull. Chem. Soc. Ethiop. 2010, 24, 457.
[15] S. Cassani, S. Kovarich, P. P. Roy, L. Van der Wal,
P. Gramatica, J. Hazard. Mater. 2013, 258-259, 50.
How to cite this article: Azzam EMS, Gad EAM,
Al-Fahemi JH. Experimental and theoretical study
on triazole derivatives as chelating agents to
remove Fe++ Ions from wastewater in oil field.
J Heterocyclic Chem. 2020;1–11. https://doi.org/10.
1002/jhet.3976