Effective Removal of the Direct Black-38 Dye from Wastewater Using a New Silica-Modified Resin: Equilibrium and Thermodynamics Modeling Studies

Ranjhan Junejo,* Shahabuddin Memon, and Savas Kaya

Article

Eﬀective Removal of the Direct Black-38 Dye from Wastewater Using

a New Silica-Modiﬁed Resin: Equilibrium and Thermodynamics

Modeling Studies

Cite This: https://dx.doi.org/10.1021/acs.jced.0c00292

Read Online

ACCESS

Metrics & More

Article Recommendations

sı Supporting Information

ABSTRACT: In this study, the synthesis of p-

diethanolaminomethylcalix[4]arene and its immobilization on a

silica surface have been performed for the removal of the direct

black (DB-38) dye from wastewater samples. The newly

synthesized p-diethanolaminomethylcalix[4]arene-immobilized

silica (DIS) resin has been analyzed and characterized by FTIR

spectroscopy and SEM techniques. To check the eﬃciency of the

DIS resin, batch and column adsorption procedures have been

applied under the optimized parameters, i.e., resin dosage, pH, and

temperature. To validate the experimental data, Langmuir,

Freundlich, and D-R models have been applied. The results

show that adsorption follows the Freundlich model well with a

good correlation coeﬃcient (R = 0.999). Moreover, the energy E (kJ/mol) was calculated with the help of the D-R model, which

suggested that the adsorption has an ion exchange nature. The DIS resin was also applied to real industrial samples of DB-38 dye

wastewater. The results show that the DIS resin removes 99% of the dye successfully. Thermodynamics studies were conducted to

know the feasibility and the mechanism of the adsorption reaction. The thermodynamic parameters show that the adsorption is

spontaneous and exothermic. The theoretical calculation was performed at the B3LYP/DZP calculation level of the ADF program,

and the power of the interaction between adsorbent and dye molecules can be determined in the light of chemical reactivity analysis.

. INTRODUCTION

due to weather conditions. The synthetic basis and their

conversion into aromatic amines help them resist degradation

because the benzidine group is formed. Therefore, these

aromatic amines are carcinogenic in nature. Consequently,

above 500 azo dyes having a carcinogenic amine origin are

Water pollution caused by the discharge of industrial eﬄuents

has caused a number of diseases in human beings and aquatic

life. These industrial eﬄuents generally contain water

pollutants, which may be organic dyes, metal ions, antibiotics,

chemicals, and many more. Among diﬀerent pollutants, water

contaminated by synthetic dyes has severe poisonous eﬀects on

human health. Dyes are basically organic synthetic com-

pounds, also called as organic colorants. They can be

synthesized by the reaction with aromatic compounds, mostly

phenol or aromatic amines and diazonium salt having the

recognized as toxic pollutants and must be removed.

Thus, keeping in view the toxicity of dyes, diﬀerent

techniques have been developed; however, adsorption remains

to be the more eﬀective method as compared to others.

Adsorption is a very simple and cheaper method that is based

upon a very basic principle where a particular species, which

may either be a negative or positive ion or a neutral molecule,

binds to a solid surface, which also has particular functionalities

and binding sites. Therefore, diﬀerent adsorbents such as

silica-based polymers, activated carbon, peat, chitin, and many

−

functional group R-N X . The azo dyes have many

important applications in textile, synthetic ﬁber, dying, and

paint industries. The plastic, paper, and glass industries as well

as many others use dyes to enhance and increase the beauty of

their products. Due to the increased consumption of azo dyes,

more than 10,000 diﬀerent dyes have been synthesized in the

9,10

other commercially available adsorbent were used previously

by many researchers throughout the world.

11−13

Mostly, the

world that produced about 70,0000 metric tons of dyes per

year. However, it is estimated that 10−15% of total dyes have

been discharged into fresh water by diﬀerent industries during

Received: March 30, 2020

Accepted: September 1, 2020

the dying process, which contains various types of unreacted

dyes.

Dye molecules have complex structures that could be

reduced into aromatic amines by the cleavage of the azo group

XXXX American Chemical Society

J. Chem. Eng. Data XXXX, XXX, XXX−XXX

Article

Figure 1. Chemical structure of the direct black (DB-38) azo dye.

adsorbents used have less selectivity and sensitivity and/or are

not regenerable. In the adsorption process, the adsorbent

should be selective and sensitive and have the ability to be

Table 1. List of Chemicals Used in Experimental Work

name of chemical/reagent

toluene

supplier

% purity

99.8%

12,14−19

Merck: CAS no.:

000108883

regenerated again and again.

In this regard, calixarenes are used as a typical class of host

molecules. Basically, calixarenes are a class of cyclic oligomers

that can be formed by a base-catalyzed reaction between

phenol and formaldehyde. Calixarenes have an upper and

lower narrow rim, which can be functionalized with diﬀerent

organic functional groups. The selectivity for recognition of

host species depends upon the functional groups present in the

host. Due to easy functionalization, calixarenes have a number

of applications in diﬀerent ﬁelds of science and technology

dichloromethane

chloroform

Supelco: CAS no.:

000075092

SAFC CAS no.: 0000067663 99.8%

Sigma: CAS no.:

0000098544

SAFC: CAS no.:

0000050000

99.8%,

-tert-butylphenol

99%

formaldehyde (37%)

solution

sodium hydroxide

5−10%

stabilizers

Sigma: CAS no.:

99%

001310732

0,21

such as catalysis, adsorbents, sensors, and so on.

Furthermore, chemical modiﬁcation of polymeric materials

was used for the elemental analysis, while the melting points

were determined using a Gallenkamp apparatus model (MFB.

such as silica with calixarenes provides a better adsorbent that

22,23

95. 010 M, England). A Thermo Nicolet 5700 FT-IR

is selective, sensitive, thermally stable, and regenerable.

spectrometer (WI. 53,711, USA) was used to record the IR

spectra. An SEM technique (JSM-6380) was applied onto the

DIS resin to characterize its surface morphology. A Quanta

Chrome ASiQwin surface area analyzer was used to examine

the surface area, pore size, and pore volume.

The silica surface can be modiﬁed with piperidine-based

calix[4]arene for the removal of the reactive blue 19 dye from

wastewater. This study also focuses on the synthesis of p-

diethanolaminomethylcalix[4]arene and its chemical attach-

ment onto a silica surface to prepare a new resin for the

removal of the toxic azo dye direct black (DB-38) from

wastewater (Figure 1).

. 2 . S y n t h e s i s . 2 . 2 . 1 . S y n t h e s i s o f p -

Diethanolaminomethylcalix[4]arene. The synthesis of com-

pounds 1 and 2 was performed via reported procedures,

24−26

while compound 3 was synthesized by the following method,

which is given in Figure 2.

. EXPERIMENTAL WORK

.1. Materials and Methods. 2.1.1. Chemicals. A list of

In a 100 mL round-bottom ﬂask, 2.0 g of compound 2 was

solubilized in 50 mL of tetrahydrofuran (THF) solution and

stirred at room temperature till the reaction mixture becomes

clear. After that, the reaction ﬂask was placed into an ice bath

and the reaction mixture was cooled with its temperature

maintained below 273 K by addition of crushed ice into the

reaction bowl. After maintaining the temperature, 5 mL of

acetic acid and 1 mL of HCHO were added, the mixture was

stirred for 15 min, then 3 mL of diethanolamine was added,

and the stirring was continued. The completion of reaction was

monitored by using basic analytical techniques such as TLC

and FTIR spectroscopy. After conﬁrmation of completion, the

reaction ﬂask was removed, 15 mL of water was added, the

solution was shaken till the solid precipitate was completely

solubilized and extracted with diethyl ether three times, then

the chemicals used in the experimental work is provided in

Table 1.

The DB-38 dye was obtained from Merck and prepared

according to its required concentration in deionized water. The

dye-contaminated water samples were collected from local

textile and dying industries of the Jamshoro Sindh-Pakistan

district. The pH of the DB-38 solution was adjusted using 0.1

N HCl or NaOH. All other chemicals used during the

experimental work were of analytical grade and GR grade.

Silica gel (230−400 mesh) was purchased from sigma Aldrich.

.1.2. Apparatus. All synthesized compounds were analyzed

by CHNS elemental analysis, melting point determination,

FTIR spectroscopy, and SEM techniques. A CHNS elemental

analyzer (model Flash EA 1112, 20,090-Rodano, Milan, Italy)

J. Chem. Eng. Data XXXX, XXX, XXX−XXX

compound 3 , as shown in Figure 3 . Therefore, 5 g of silica was

Article

C_i− C_f

%adsorption =

× 100

C_i

(1)

In this equation, C and C stand for the initial and ﬁnal

concentrations of the DB-38 dye. The amount of dye (q in

mol/g) adsorbed onto the DIS resin can be calculated using eq

_q₌(

C − C )V

(

In eq 2, C and C are the initial and ﬁnal concentrations

mol/L) while V is the volume (mL) of the DB-38 solution

(

and m is the weight (in g) of the DIS resin.

Figure 2. Synthesis scheme of p-diethanolaminomethylcalix[4]arene

(

3). Reagents: (i) NaOH/HCHO, (ii) AlCl /phenol, and (iii)

3. RESULTS AND DISCUSSION

diethanolamine/HCHO/acetic acid.

.1. FTIR Spectroscopy. FT-IR spectroscopy is the most

0 mL of 10% K CO solution was added, and the product was

2 3

important technique to identify the functional group present in

a compound. The chemical modiﬁcation of the silica surface

was conﬁrmed by FT-IR spectroscopy to analyze the functional

ﬁltered. After drying and recrystallization, white crystals were

obtained and weighed and the % yield was calculated.

7,28

.2.2. Synthesis of DIS Resin. The DIS resin was prepared

groups.

Therefore, the synthesized compounds were

by the modiﬁcation of the silica surface by attachment of

analyzed by FTIR spectroscopy, as shown in Figure 4. The

spectrum in Figure 4a is for p-diethanolaminomethylcalix[4]-

arene, which comprises some characteristic bands at 3351,

−

914, 1680, 1288, and 1027 cm for OH, C−H, CC, C−N,

−

and C−O stretching, respectively while the peak at 1388 cm

is attributed to C−OH bending. The spectrum in Figure 4b is

for pure silica powder, which has characteristic peaks at 3479

−

and 1614 cm attributed to OH and Si−O stretching while

−

that at 1076 cm is attributed to Si−OH bending peak. The

spectrum in Figure 4c is for the DIS resin, which has some new

−

bands at 3404, 2921, and 1457 cm , which are peaks

attributed to OH, C−H, and CC vibrations and the peak at

084 to OH bending. These additional new peaks found for

silica conﬁrm the immobilization of compound 3 onto the

silica surface.

3.2. SEM Characterization of the DIS Resin. Scanning

electron microscopy is the most versatile technique to analyze

Figure 3. Synthesis route of the DIS resin.

the surface of materials. Therefore, the DIS resin was

characterized by an SEM technique as shown in Figure 5.

Figure 5a is the image of pure silica, which is smooth and

crystalline and has a speciﬁc geometry. Meanwhile, Figure 5b is

the SEM image of the DIS resin (4), which is obtained after

the attachment of compound 3 onto the silica surface. The

roughness observed in the image of Figure 5b is due to the

attachment of compound 3 onto the silica surface. Such a type

of material was also prepared in previous studies for the

weighed, treated with 0.1 M HCl, then washed with deionized

water, and dried at 393 K for 3 h. After cooling the silica, 50

mL of 0.01 M SiCl solution and 10 mL of triethylamine were

added, resulting in a cloudy solution mixture, which was placed

at room temperature for 6 h. After removing the solvent by

vacuum, 1.5 g of compound 3 solubilized in chloroform was

poured into it followed by addition of 8 mL of triethylamine,

and the mixture was reﬂuxed at 523 K. The reaction was

monitored by FTIR spectroscopy. After 36 h, grayish resin 4

was ﬁltered, washed with 150 mL each of chloroform,

methanol, and ﬁnally water, and dried.

27,28

adsorption of RB-5, RR-45, and DB-38 dyes.

Moreover,

the DIS resin particles look smaller in size as compared to

those of silica in Figure 5a and a smaller particle size will lead

to a larger surface area and make the material be able to

remove more analytes.

.3. Adsorption. 2.3.1. Batch Adsorption. The batch

adsorption study was performed to analyze the DB-38 dye

adsorption potential of the DIS resin. During adsorption

experiments, the resin amount, pH of DB-38 dye solution, and

contact time were optimized and the role of electrolyte and the

temperature eﬀect were determined. A dye solution (10 mL, 2

3.3. Pore Size Distribution (PSD). The PSD of the DIS

resin from their nitrogen adsorption isotherms was determined

by applying the ASiQwin and non-local density functional

theory (NLDFT) model in SAIEUS. The nitrogen adsorp-

tion−desorption isotherms at 77 K are given in Figure 6, which

−

10 mol/L) with 60 mg of DIS resin was placed onto a

mechanical shaker at a speed of 130 rpm for 1 h. After 1 h, the

shows a type-IV isotherm in the range of 0.6−09 P/P , and the

speciﬁc surface area calculated by the BET technique was

DIS resin was ﬁltered and the concentration of remaining DB-

27.8630 m /g. The calculated PSDs clearly show that the

8 was analyzed using a UV−vis spectrophotometer. The %

porous structure of the DIS resin in 2D-NLDFT mode has a

less than 3 nm pore size.

adsorption of DB-38 was determined using eq 1.

J. Chem. Eng. Data XXXX, XXX, XXX−XXX

Article

Figure 4. FTIR spectrum of (a) p -diethanolaminomethylcalix[4]arene, (b) pure silica, and (c) the DIS resin.

signiﬁcant role in the entire adsorption process because it

aﬀects the adsorbate and adsorbent binding sites. In this

regard, the eﬀect of pH from acidic to basic has been

investigated, which is given in Table S2 and Figure 8. In Figure

, it is noticed that the % removal decreases with increasing pH

and maximum % removal was achieved at pH 3. Below pH 3,

there is no signiﬁcant diﬀerence in % removal, and above pH 3,

removal decreases. Thus, at acidic pH, the sulfur and amine

groups of the DB-38 dye molecule are protonated and can

attract electron-donating groups present in the DIS resin.

Similarly, OH groups in the DIS resin become active and

attract the negative part of the DB-38 dye and the overall net

charges tightly bind the dye molecule to the DIS resin.

Previously, diﬀerent studies were performed using other dyes

such as Evans blue and Chicago sky blue B6, which were

removed successfully using carboxylic calix[4]arene magnetic

Figure 5. SEM images of (a) silica and (b) the DIS resin (after

modiﬁcation of the silica surface).

(

CCM) nanoparticles at pH 2.5. Another study was

. ADSORPTION PARAMETERS

.1. Eﬀect of Adsorbent Dosage. To optimize the DIS

performed using 25,26,27,28-tetrakis-(N,N-diethy-l,2-amino-

ethylamidomethoxy)-calix[4]arene-based Amberlite XAD-4

resin for the eﬀective removal of MO and MR dyes from

resin dosage, diﬀerent experiments were performed ranging

from 10−100 mg/L DIS resin dosages given in Table S1 and

Figure 7. During the adsorption, it was observed that

increasing the amount of DIS resin, the % adsorption increases

due to the increasing amount of binding sites of the DIS resin

for the DB-38 dye molecule. It is clear in Figure 7 that 99.1%

of the DB-38 dye was removed using only 60 mg of DIS resin;

increasing further the dosage was found to have no signiﬁcant

eﬀect on the % removal of the DB-38 dye. In the literature, a

similar phenomenon has been observed for the adsorption of

water at pH 3. The novel derivative pyrazine-2-carboxylate-

substituted calix[4,8]arene was used for the removal of reactive

black (RB-5), trapeolin 000 (TP), Evans blue (EB), and

Chicago sky blue at pH 3.

.3. Eﬀect of Temperature and Time. The temperature

has a great role in the removal of the DB-38 dye as a function

of contact time between the DIS resin and dye molecules.

Therefore, adsorption of the DB-38 dye has been examined at

various temperatures (293−308 K), as given in Table S3 and

Figure 9, and it has been noticed that % removal decreases

with the increase in temperature from 293−303 K, which

3,30

RB-19,

.2. Optimization of pH. The % removal of the DB-38

dye from water depends on the pH value, which plays a

MB, Evans blue, and Chicago sky blue B6.

J. Chem. Eng. Data XXXX, XXX, XXX−XXX

Figure 6. 2D-NLDFT-based pore size distributions.

Article

Figure 7. Eﬀect of DIS resin dosages (10 mL of dye, 2 × 10⁻⁵mol/L,

20 min shaking time).

Figure 9. Eﬀect of temperature on % adsorption of the DB-38 dye

attached to the DIS resin (10 mL, 2 × 10 M, 60 mg of DIS resin).

−

obtained in 45 min at various temperatures, and further

increasing the time up to 45 min has no major eﬀect on the %

removal of the DB-38 dye. This may be due to the decrease in

the binding forces between the DB-38 dye and DIS resin.

Increasing the temperature decreases the dye adsorption,

which was reported in diﬀerent studies. The adsorption of

methylene blue has been performed, and it has been observed

that the % adsorption decreases with increasing temperature.

Another study reported that the adsorption of dyes such as

methyl violet (MV), methyl green (MG), and methylene blue

(

MB) decreased with increasing temperature.

. ADSORPTION ISOTHERM

Figure 8. Eﬀect of pH on DB-38 removal from water (10 mL, 2 ×

−

mol/L, 60 mg of DIS resin)

Isotherm models describe the adsorption phenomenon;

therefore, experimental data were subjected to Langmuir,

Freundlich, and Dubinin−Radushkevich (D-R) isotherm

clearly demonstrates that the adsorption mechanism between

DB-38 and the DIS resin is exothermic, the equilibrium was

models and their linear forms are given below in eqs 3−5

J. Chem. Eng. Data XXXX, XXX, XXX−XXX

Journal of Chemical & Engineering Data

0 . The Langmuir constant values are given in Table 2 and

Article

Table 3. Fruendlich Isotherm Parameters

e z

z = j z + j

{

_A₍_m_g_g−1

_R2

temperature

)

1/n

(

ads {

{

26,696

7729.0

3210

1.28

1.12

1.11

1.10

0.983

0.999

i l y

j z

303

308

log C = log A + j zlog C

ads

j z

k n {

1351

ln C = ln X − βε

where C (mol/L) is the equilibrium concentration of the

(5)

ads

DB-38 dye in solution, C (mol/g) is the amount of DB-38

ads

dye on the adsorbent surface, Q describes the maximum

amount of dye adsorbed, which implies the monolayer

coverage of the adsorbent surface, b is a Langmuir constant

that shows the binding energy of the dye, A is the Freundlich

constant, and 1/n shows the adsorption intensity.

Thus, the Langmuir model has been applied by plotting the

graph in between C /C_a_d_sversus C , and a straight line has

been obtained with its regression coeﬃcient shown in Figure

Figure 11. Freundlich model graph between log C (mol/L) and log

−9

−5

C_a_d_s(2 × 10 to 2 × 10 mol/L, with 20 min time and 60 mg of DIS

resin).

adsorption reaction. The very important factor of this model is

the Polanyi potential, denoted by (ε), which can be calculated

using eq 7.

ε = RTlnj1 +

{

(7)

where T is the temperature in Kelvin (K), R is the gas

constant, which has the unit kJ/mol K, and E describes the

mean adsorption energy given in eq 8.

Figure 10. Langmuir graph between C (mol/L) and C /C (2 ×

ads

−

−5

to 2 × 10 mol/L, with 20 min time and 60 mg of DIS resin).

Table 2. Langmuir Isotherm Parameters

E −

−

2β

(8)

temperature

Q (mol/g)

R_L

R²

298

303

308

313

7.28

3.42

2.95

2.36

0.041

0.062

0.065

0.067

0.99−0.21

0.99−0.22

0.99−0.12

0.99−0.13

0.996

0.952

0.987

0.981

Whenever ε was plotted against ln C_a_d_s(mol/g), a straight

line would be obtained from the diagram with a good

correlation coeﬃcient value (R = 0.999), which is shown in

Table S6 and Figure 12. In Table 4, the values of X (mol/g)

and E (kJ/mol) demonstrate that the adsorption of the DB-38

dye onto the DIS resin is via resin ion exchange.

obtained from the slope and intercept of the graph. The

characteristics of the Langmuir model can be demonstrated by

R_L, known as a separation factor and can be calculated using eq

, where b is a constant and C is the initial concentration

(Table S4 ).

R_L= ₁

+ bC_i

(6)

The Freundlich isotherm model describes multilayer

formation onto an adsorbent surface. In this regard, eq 10

was applied; the graph was plotted between log C_a_d_s(mol/g)

and log C and A and n can be calculated from this graph,

which are given in Table S5, Table 3, and Figure 11. The

constant parameter values of this model explain that the

adsorption follows a multilayer formation rather than the

Langmuir model.

The D-R isotherm model is applicable to describe the

adsorption nature and calculate energy E (kJ/mol) used in the

Figure 12. D-R isotherm plot (2 × 10⁻to 2 × 10⁻⁵mol/L, with 20

min time and 60 mg of DIS resin).

J. Chem. Eng. Data XXXX, XXX, XXX−XXX

Journal of Chemical & Engineering Data

(R = 0.991) (Figure 13 ). From the slope and intercept, the

Article

Table 4. D-R Isotherm Parameters

in the Hyderabad district, Sindh, Pakistan. The DIS resin (60

mg) was added into 10 mL of dye-contaminated wastewater

sample. The results shows that the DIS resin has a good %

recovery of 98.9%, and also the values of pH, TDS,

conductivity, and salinity of real wastewater samples were

normalized after treatments and are given in Table 6.

temperature

X_m(mmol/g)

E (kJ/mol)

R²

0.183

0.176

0.161

0.153

12.98

11.91

11.41

10.33

0.999

Table 6. Real Wastewater Sample Values before and after

Treatment with DIS Resin

. THERMODYNAMICS STUDY

A thermodynamics study was performed for the adsorption of

the DB-38 dye from water with a temperature range from

wastewater before

treatment with DIS

resin

wastewater after

treatment with DIS

resin

93−303 K and a graph was plotted between ln k and 1/T: a

parameter

% recovery

straight line was obtained with a good correlation coeﬃcient

conc (mol/L)

−4

−5

.2 × 10

2.0 × 10

83.34

92.81

95.33

.2 × 10⁻

.5 × 10⁻

2.3 × 10

−5

2.1 × 10

7.8

7.5

7.3

TDS (mg/L)

220

250

190

conductivity

(μS/cm)

880.92

560.87

090.72

430

320

490

Figure 13. Eﬀect of temperature on the adsorption of the DB-38 dye

onto the DIS resin.

salinity

0.08

0.06

0.07

values of the enthalpy (ΔH) and entropy (ΔS) can be

calculated using eq 9 while the Gibbs free energy (ΔG) was

calculated using eq 10; and constant parameter values are listed

in Table 5.

. REUSABILITY OF THE DIS RESIN

Table 5. Thermodynamic Constant Parameters for the

Adsorption of the DB-38 Dye onto the DIS Resin

The DIS resin can be used many times by washing with

methanol and water at a 1:5 ratio, which is the most important

feature of this material. Figure 14 clearly shows that there is no

change observed in the eﬃciency of the DIS resin after many

cycles conﬁrming its reusability.

ΔG (kJ/mol)

ΔH (kJ/mol) ΔS (kJ/mol/K)

0.0146 −0.0227

293 K

−6.33

ln k = 2.6

303 K

−5.70

ln k = 2.3

308 K

−4.50

ln k = 1.8

−

9. THEORETICAL EXPLANATION FOR ADSORPTION

In the theoretical part of this study, the optimization of studied

dye molecules was performed at the B3LYP/DZP calculation

level of the ADF program. The power of the interaction

−

ΔH

ΔS

ln k =

(9)

ΔG = RTln k_c

(10)

The numerical values of the thermodynamic parameters are

listed in Table 5 in which the negative value of ΔG shows the

spontaneity of the DB-38 dye adsorption process onto the DIS

resin, while the negative value of ΔH explains that the

adsorption reaction is exothermic in nature and the value of ln

k_cdecreasing with the rise in temperature shows that the

reaction is independent and spontaneous. Moreover, the low

ΔS value describes the randomness being increased during the

adsorption reaction at the DIS resin surface.

. REAL WASTEWATER SAMPLE ANALYSIS

The eﬀectiveness of the DIS resin was determined by applying

real dye wastewater samples obtained from industrial eﬄuents

Figure 14. Reusability DIS resin after many cycles.

J. Chem. Eng. Data XXXX, XXX, XXX−XXX

Article

Figure 15. Partial charges on atoms of the dye molecule.

between adsorbent and dye molecules can be determined in

the light of chemical reactivity analysis. In conceptual density

of chemical species. According to the maximum hardness

principle, chemical hardness can be considered as a measure

of the stability of chemical species and hard molecules are less

reactive than soft molecules. It is apparent from the chemical

hardness data obtained for the studied dye molecule that this

molecule is very soft and gives the electrons to the adsorbent

easily. Hard and soft acid−base principle states that “Hard

molecules prefer to coordinate to hard bases and soft

molecules prefer to coordinate to soft bases.” In a recent

functional theory, chemical reactivity descriptors such as

chemical hardness (η), chemical potential (μ), electro-

negativity (χ), and softness (σ) are deﬁned within the

framework of eqs 11−13 based on the ionization energy (I),

electron aﬃnity (A), and frontier orbital (HOMO and

LUMO) energies of molecules.

i I + A y

−EHOMO − ELUMO

x = −μ = j

z =

paper, Kokalj showed that in the explanation of the power of

{

(

11)

the interactions in the adsorption process, the HSAB principle

is very useful. In the same paper, he noted that the HSAB

principle estimates the charge transfer between the adsorbate

and metal surfaces. In Figure 15, partial charges on atoms of

the studied dye molecule are given in detail. In this way, we

detected the most suitable regions for the formation of

hydrogen bonds. Hydrogen bonds occur as a result of the

electrostatic interaction between one electronegative atom and

the hydrogen bonded to another electronegative atom. It is

important to note that this interaction has a key role in many

adsorption processes. The strength of the adsorption between

adsorbent and dye molecules can be explained by considering

the hydrogen bonds formed.

I − A

− E_H_O_M_O

LUMO

η =

(12)

σ = 1/η

(13)

Calculated HOMO and LUMO orbital energies for the

studied dye molecule at the aforementioned calculation level

are −6.05 and − 4.22 eV, respectively. In light of this

information, one can say that the chemical hardness value of

the dye molecule is 0.915 eV. In many papers written by Kaya

9,40

and coworkers,

chemical hardness is deﬁned as the

resistance toward electron cloud polarization or deformation

J. Chem. Eng. Data XXXX, XXX, XXX−XXX

Journal of Chemical & Engineering Data

0. COMPARATIVE STUDY

Complete contact information is available at:

Article

Authors

Shahabuddin Memon − National Centre of Excellence in

Analytical Chemistry, University of Sindh, Jamshoro 76080,

Pakistan

Savas Kaya − Health Services Vocational School, Department of

Pharmacy, Sivas Cumhuriyet University, 58140 Sivas, Turkey

The synthetic adsorbent plays a very crucial role in the

treatment of these toxicants. Therefore, a very huge number of

synthetic materials are available and their adsorption

eﬃciencies are comparable with those of the present

adsorbent, which are shown in Table 7.

https://pubs.acs.org/10.1021/acs.jced.0c00292

Table 7. Maximum % Adsorption of Diﬀerent Adsorbents

adsorbent

dyes

DB-38

% adsorption

91%

refs

Notes

p-tert-butylcalix[6]arene-

based silica resin

graphene oxide (GO)

salphonated calix[4]arene

The authors declare no competing ﬁnancial interest.

MB, CV, MO,

and EY

80−90%

ACKNOWLEDGMENTS

■

(

SC)

We are thankful to the National Centre of Excellence in

Analytical Chemistry, University of Sindh Jamshoro for their

support and help.

CELF aminated lignin

product

Fe O /C−COP

DB-1

90%

auramine O and

rhodamine B

malachite Green

RB-5 and DB-38

95−96%

REFERENCES

MWCNT-OH−Pd-NPs

calix[6]arene-appended

XAD-4 resin

96%

88%

■

1) Parchebaf Jadid, A.; Nojameh, G. Modified nano-γ -alumina with

2, 4-dinitrophenyl hydrazine as an efficient adsorbent for the removal

of everzol red 3BS dye from aqueous solutions. Eurasian Chem.

Commun. 2019, 2, 395−490.

DIS resin

DB-38

99.1%

present

study

2) Liu, X.; Tian, J.; Li, Y.; Sun, N.; Mi, S.; Xie, Y.; Chen, Z.

Enhanced dyes adsorption from wastewater via Fe3O4 nanoparticles

functionalized activated carbon. J. Hazard. Mater. 2019, 373, 397−

3) Jiang, C.; Wang, X.; Qin, D.; Da, W.; Hou, B.; Hao, C.; Wu, J.

07.

1. CONCLUSIONS

In this study, the synthesis of the DIS resin and its usage for

the adsorption of the DB-38 dye from water are reported. It

could be concluded that the adsorption of DB-38 on the DIS

resin is pH-dependent. The most eﬀective adsorption of DB-38

has been observed at acidic pH, and further a higher pH is not

favorable. The adsorption equilibrium data follow the

Freundlich model very well with a good correlation coeﬃcient

Construction of magnetic lignin-based adsorbent and its adsorption

properties for dyes. J. Hazard. Mater. 2019, 369, 50−61.

(4) Kamboh, M. A.; Solangi, I. B.; Sherazi, S. T. H.; Memon, S.

Synthesis and application of calix [4] arene based resin for the

removal of azo dyes. J. Hazard. Mater. 2009, 172, 234 −239.

(5) Gungor, O.; Yilmaz, A.; Memon, S.; Yilmaz, M. Evaluation of the

performance of calix [8] arene derivatives as liquid phase extraction

material for the removal of azo dyes. J. Hazard. Mater. 2008, 158,

value, i.e., R = 0.999. The adsorption of the DB-38 dye

6) Memon, S.; Bhatti, A. A.; Bhatti, A. A.; Solangi, I. B. Synthesis

02−207.

decreased with increasing temperature. The values of ΔH and

ΔS are −0.0146 and −0.0227, respectively, which demonstrate

that the adsorption is exothermic and decreases the random-

ness, while the values of ΔG are −6.12,−4.19, and −3.23,

which show that the adsorption is spontaneous. The DIS resin

was applied on real wastewater samples too, and it has been

found that the DIS resin has very good % recovery. The

reusability of the DIS resin shows that there is no signiﬁcant

change in % adsorption or removal eﬃciency after using many

times. The adsorption mechanism was described with the help

of DFT calculations, which revealed the chemical nature of the

dye and the adsorbent binding energies very well.

and adsorption efficiency of calix [6] arene appended XAD-4 resin.

Desalin. Water Treat. 2016, 57, 1844−1856.

(7) Erdemir, S.; Bahadir, M.; Yilmaz, M. Extraction of carcinogenic

aromatic amines from aqueous solution using calix [n] arene

derivatives as carrier. J. Hazard Mater. 2009 , 168 , 1170 −1176.

(8) Memon, F. N.; Memon, S. Sorption and desorption of basic dyes

from industrial wastewater using calix [4] arene based impregnated

material. Sep. Sci. Technol. 2015 , 50 , 1135 −1146.

(9) Camel, V. Solid phase extraction of trace elements. Spectrochim.

Acta, Part B 2003, 58, 1177−1233.

(10) Starvin, A. M. Oﬄine and online solid phase extraction/

preconcentration of inorganics. Ph. D Thesis, Cochin University of

Science and Technology, (Council of Scientiﬁc and Industrial

Research Regional Research Laboratory Industrial Estate P.O.,

Thiruvananthapuram - 695019, India, 2005.

ASSOCIATED CONTENT

sı Supporting Information

The Supporting Information is available free of charge at

https://pubs.acs.org/doi/10.1021/acs.jced.0c00292.

■

(11) Kamboh, M. A.; Solangi, I. B.; Sherazi, S. T. H.; Memon, S. A

highly efficient calix [4] arene based resin for the removal of azo dyes.

Desalination 2011, 268, 83−89.

Removal of the DB-38 dye performed at the optimized

dosage, pH eﬀect, and temperature optimization and

adsorption phenomenon at various concentrations and

diﬀerent temperatures (PDF)

(12) Memon, S.; Memon, F. N.; Durmaz, F.; Memon, N. A.;

Memon, A. A.; Kara, H. Simultaneous determination of some basic

dyes using p-tetranitrocalix [4] arene-appended silica-based HPLC

column. Anal. Methods 2014, 6, 7318−7323.

(13) Ghasemi, A. S.; Ashrafi, F.; Tavasoli, T. M.; Hoosini, M.;

Norouzi, M.; Karimnia, M.; Sadeghi, A. Studying physicochemical

characteristics of Flutamide adsorption on the Zn doped SWCNT

AUTHOR INFORMATION

Corresponding Author

Ranjhan Junejo − National Centre of Excellence in Analytical

Chemistry, University of Sindh, Jamshoro 76080, Pakistan;

orcid.org/0000-0002-0090-1146; Email: ranjhanjunejo@

yahoo.com

■

14) Afshar, M.; Ranjineh khojasteh, R.; Ahmadi, R. Adsorption of

5,5), using DFT and MO calculations. Eurasian Chem. Commun.

020, 2, 138−149.

lomustin anticancer drug on the surface of carbon nanotube: A

theoretical study. Eurasian Chem. Commun. 2020, 2, 595−603.

J. Chem. Eng. Data XXXX, XXX, XXX−XXX

Journal of Chemical & Engineering Data

Article

15) Parchebaf, A.; Nojameh, G. Modified nano-γ -alumina with 2, 4-

concentration, biomass dosage, rotation and ionic strength. J. King

Saud Univ. Eng. Sci. 2019, 351.

dinitrophenyl hydrazine as an efficient adsorbent for the removal of

everzol red 3BS dye from aqueous solutions. Eurasian Chem. Commun.

(36) Mate, C. J.; Mishra, S. Synthesis of borax cross-linked Jhingan

gum hydrogel for remediation of Remazol Brilliant Blue R (RBBR)

dye from water: Adsorption isotherm, kinetic, thermodynamic and

biodegradation studies. Int. J. Biol. Macromol. 2020, 151, 677−690.

(37) Te Velde, G. t.; Bickelhaupt, F. M.; Baerends, E. J.; Fonseca

Guerra, C.; van Gisbergen, S. J.; Snijders, J. G.; Ziegler, T. Chemistry

with ADF. J. Comput. Chem. 2001, 22, 931−967.

(38) Islam, N.; Kaya, S. Conceptual Density Functional Theory and Its

Application in the Chemical Domain; CRC Press: Taylor and Francis

group, ISBN 9781771886659, Toronto, 2018.

16) Shahzad, H.; Ahmadi, R.; Najafpour, J.; Adhami, F. Adsorption

020, 2, 475−490.

of Cytarabine on the Surface of Fullerene C20: A Comprehensive

DFT Study. Eurasian Chem. Commun. 2020, 2, 162−169.

(17) Fereydoun Asl, E.; Mohseni-Shahri, F. S.; Moeinpour, F.

NiFe2O4 coated sand as a nano-adsorbent for removal of Pb (II)

from aqueous solutions. Eurasian Chem. Commun. 2019, 1, 480−493.

(18) Olasehinde, E. F.; Abegunde, S. M. Adsorption of Methylene

Blue onto Acid Modiﬁed Raphia Taedigera Seed Activated Carbon.

Adv. J. Chem. Sect. A 2020.

(39) Kaya, S.; Kaya, C. A new method for calculation of molecular

hardness: a theoretical study. Comput. Theor. Chem. 2015, 1060, 66−

70.

(19) Junejo, R.; Memon, S.; Palabiyik, I. M. Efficient adsorption of

heavy metal ions onto diethylamine functionalized calix [4] arene

based silica resin. Eurasian Chem. Commun. 2020 , 2 , 785 −797.

(40) Kaya, S.; Kaya, C. A simple method for the calculation of lattice

energies of inorganic ionic crystals based on the chemical hardness.

Inorg. Chem. 2015, 54, 8207−8213.

(20) Schalley, C. A. Molecular recognition and supramolecular

chemistry in the gas phase. Mass Spectrom. Rev. 2001, 20, 253−309.

21) Morohashi, N.; Narumi, F.; Iki, N.; Hattori, T.; Miyano, S.

Thiacalixarenes. Chem. Rev 2006, 106, 5291−5316.

22) Hutchinson, S.; Kearney, G. A.; Horne, E.; Lynch, B.; Glennon,

(41) Kaya, S.; Kaya, C.; Islam, N. Maximum hardness and minimum

polarizability principles through lattice energies of ionic compounds.

Phys. B 2016, 485 , 60 −66.

(

(42) Kokalj, A. On the HSAB based estimate of charge transfer

J. D.; McKervey, M. A.; Harris, S. J. Solid phase extraction of metal

ions using immobilised chelating calixarene tetrahydroxamates. Anal.

Chim. Acta 1994, 291, 269−275.

between adsorbates and metal surfaces. Chem. Phys. 2012 , 393 , 1 −12.

(43) Narula, A.; Rao, C. P. Hydrogel of the Supramolecular

Complex of Graphene Oxide and Sulfonatocalix [4] arene as Reusable

Material for the Degradation of Organic Dyes: Demonstration of

Adsorption and Degradation by Spectroscopy and Microscopy. ACS

Omega 2019, 4, 5731−5740.

(23) Junejo, R.; Memon, S.; Memon, F. N.; Memon, A. A.; Durmaz,

F.; Bhatti, A. A.; Bhatti, A. A. Thermodynamic and Kinetic Studies for

Adsorption of Reactive Blue (RB-19) Dye Using Calix [4] arene-

Based Adsorbent. J. Chem. Eng 2019, 64, 3407−3415.

(

44) Meng, X.; Scheidemantle, B.; Li, M.; Wang, Y.-y.; Zhao, X.;

(24) Gutsche, C. D.; Dhawan, B.; No, K. H.; Muthukrishnan, R.

Toro-Gonzalez, M.; Singh, P.; Pu, Y.; Wyman, C. E.; Ozcan, S.; Cai,

Calixarenes. 4. The synthesis, characterization, and properties of the

calixarenes from p-tert-butylphenol. J. Am. Chem. Soc. 1981, 103,

C. M. Synthesis, Characterization, and Utilization of a Lignin-Based

Adsorbent for Effective Removal of Azo Dye from Aqueous Solution.

ACS Omega 2020, 5, 2865−2877.

25) Gutsche, C. D.; Lin, L.-G. Calixarenes 12: the synthesis of

782−3792.

functionalized calixarenes. Tetrahedron 1986 , 42 , 1633 −1640.

26) Gutsche, C. D.; Nam, K. C. Calixarenes. 22. Synthesis,

45) Shakeri, S.; Rafiee, Z.; Dashtian, K. Fe O -Based Melamine-

3 4

Rich Covalent Organic Polymer for Simultaneous Removal of

(46) Borousan, F.; Yousefi, F.; Ghaedi, M. Removal of Malachite

Auramine O and Rhodamine B. J. Chem. Eng. 2020 , 65 , 696 −705.

properties, and metal complexation of aminocalixarenes. J. Am. Chem.

Soc. 1988, 110, 6153−6162.

Green Dye Using IRMOF-3 −MWCNT-OH −Pd-NPs as a Novel

Adsorbent: Kinetic, Isotherm, and Thermodynamic Studies. J. Chem.

Eng. 2019, 64, 4801−4814.

(27) Kamboh, M. A.; Solangi, I. B.; Sherazi, S. T. H.; Memon, S.

Synthesis and application of p-tert-butylcalix [8] arene immobilized

material for the removal of azo dyes. J. Hazard Mater. 2011, 186,

(

51−658.

28) Kamboh, M. A.; Bhatti, A. A.; Solangi, I. B.; Sherazi, S. T. H.;

Memon, S. Adsorption of direct black-38 azo dye on p-tert-butylcalix

6] arene immobilized material. Arab. J. Chem. 2014, 7, 125−131.

29) Goldstein, J. I.; Newbury, D. E.; Michael, J. R.; Ritchie, N. W.;

[

(

Scott, J. H. J.; Joy, D. C. Scanning electron microscopy and X-ray

microanalysis. Springer, 2017.

(30) Bhatti, A. A.; Kamboh, M. A.; Solangi, I. B.; Memon, S.

Synthesis of calix [6] arene based XAD-4 material for the removal of

reactive blue 19 from aqueous environments. J. Appl. Polym. Sci. 2013,

(

30, 776−785.

31) Kamboh, M. A.; Wan Ibrahim, W. A.; Rashidi Nodeh, H.;

Zardari, L. A.; Sherazi, S. T. H.; Sanagi, M. M. p-Sulphonatocalix-

8]arene functionalized silica resin for the enhanced removal of

[

methylene blue from wastewater: equilibrium and kinetic study. Sep.

Sci. Technol. 2019, 54, 2240−2251.

(32) Bhatti, A. A.; Oguz, M.; Yilmaz, M. Magnetizing calixarene: Azo

dye removal from aqueous media by Fe O nanoparticles fabricated

with carboxylic-substituted calix [4] arene. J. Chem. Eng. Data 2017,

2, 2819−2825.

33) Memon, S.; Bhatti, A. A.; Bhatti, A. A. Calix [4] arene resin, an

efficient adsorbent for azo dyes. Polycycl Aromat. Compd. 2019, 39,

38−247.

34) Gungo

r, O. Efficient removal of carcinogenic azo dyes by novel

pyrazine-2-carboxylate substituted calix [4, 8] arene derivatives.

Supramol. Chem. 2019, 31, 776−783.

(

35) de Farias Silva, C. E.; da Gama, B. M. V.; da Silva Gonc a ̧ lves, A.

H.; Medeiros, J. A.; de Souza Abud, A. K. Basic-dye adsorption in

albedo residue: Effect of pH, contact time, temperature, dye