Article http://sciencetechindonesia.com

Article History
Received: 26 February 2017 
Received in revised form: 9 May 2017
Accepted: 15 May 2017

DOI: 10.26554/sti.2017.2.3.71-75
©2017 Published under the term of  the CC BY NC SA license

Science & Technology Indonesia
p-ISSN: 2580-4405 e-ISSN: 2580-4391
Sci. Technol. Indonesia 2 (2017) 71-75

PILLARIZATION OF LAYER DOUBLE HYDROXIDES (Mg/Al) WITH KEGGIN TYPE K4[a-Si-
W12O40].nH2O AND ITS APPLICATION AS ADSORBENT OF PROCION RED DYE
 
Intan Permata Sari1, Muhammad Said1, Aldes Lesbani1*

1Department of  Chemistry, Faculty of  Mathematic and Natural Sciences, Sriwijaya University
*Corresponding Author E-mail : aldeslesbani@yahoo.com

ABSTRACT
Pillarization of  layered double hydroxides with polyoxometalate K

4
[α-SiW

12
O

40
]•nH

2
O at various times i.e. 3, 6, 9, 12, 24, 36 and 48 hours has been 

done. The pillared product was characterized by FT-IR spectrophotometer and XRD. The optimum pillared layered double hydroxides of  polyoxo-
metalate K

4
[α-SiW

12
O

40
]•nH

2
O was used as adsorbent of  procion red dye. The results of  characterization using FT-IR spechtrophotometer is not 

yet show the optimum pillaration process. The characteritation using XRD the successfully of  pillared layered double hydroxides of  polyoxometalate 
K

4
[α-SiW

12
O

40
]•nH

2
O showing the existence of  diffraction angle 8.5o with intensity 355. Furthermore, the pillared layered double hydroxides of  poly-

oxometalate K
4
[α-SiW

12
O

40
]•nH

2
O with time variation of  12 hours was applied as adsorbent of  procion red dye. The results show the adsorption rate 

was 0.523 min-1, the highest of  absorption capacity at 70oC was 10.8 mol/g, the higest energy of  absorption 70 oC was 125 kJ/mol. The enthalpy (∆H) 
and entropy (∆S), decrease as the increasing consentration of  procion red dye. 

Keywords: layered double hydroxides, polyoxometalate, pillaration, procion red, adsorption

INTRODUCTION
Layered material based on his being is divided into a layered material 

found in nature and are synthesized. One example of  a layered double hy-
droxide compounds synthesized double layer. Hydrotalcite is layered ma-
terial and has general formula [M2+

(1-x)
M3+x(OH)

2
](An-)x/n•nH

2
O, where 

M
2
 and M

3
 is divalen and trivalen metal cations and An intercultural space 

is filled by the compound layer hydra (Zhao et al, 2011). Recently, layer 
double hydroxides are modified by insertion or intercalation between layer 
using anion (Maruyama et.al, 2016) or macoanion such as polyoxometalate 
compounds (Asiabi et.al, 2017).  

Layered double hydroxides modified with the purpose of  enlarging 
the spacing layer so that it can be effectively used as adsorbent. Modifi-
cation of  layered double hydroxide do with macroanion pillared process. 
Macroanion compound used was polyoxometalate Keggin type H

3
[α-

PW
12

O
40

].nH
2
O. The pillared method is used on layered double hydroxide 

i.e. ion exchange method. Pillarization of  macroanion in double layers of  
hydroxides cause material loss of  the anion OH-which located on the layer 
so that it is expected to enlarge the distance between layers of  material 
layered double hydroxide (Imron and Said, 2017). Polyoxometalates are 
metal oxygen clusters with various structures, acid base properties, redox 
properties, and also high solubility depanding on counterions (Misuno, 
2013). Polyoxometalate is macroanions, which can be used frequently as 
intercalant for layer double hydroxides (Omwoma et.al, 2014 ; Hasannia 
and Yadollahi, 2015). 

Layered material is used as a catalyst, adsorbent, sensor, membrane or 
ion exchange. As adsorbent, a layered material used for aditive adsorption 
on vegetable oil, as well as its application for the control of  contamination 
of  metal ions or organic compounds in the environment. In the industrial 
field, most of  the dyes that have been used will be discharged into the 
environment. Generally, the dyestuff  from the textile industry waste is 
an organic compound which has an aromatic structure so it is difficult to 
degrade naturally and certainly not environmentally friendly (Ba-Abbad, 
et al. 2017).

This research was conducted on the synthesis and characterization of  

layered double hydroxides, compounds polyoxometalate K
4
[α-SiW

12
O

40
].

nH
2
O and layered double hydroxides pillared  polyoxometalate K

4
[α-Si-

W
12

O
40

].nH
2
O.  The successfully pillarization process, material was charac-

terized using FTIR and XRD analyses. Furthermore, pillared material was 
used as adsorbent of  procion red dye. Procion red are toxic and difficult to 
degraded because it has a complex chemical structure and the presence of  
aromatic rings. The adsorption process was studied by adsorption time, in-
fluence of  temperature and concentrations. Concentration of  procion red 
dye was determined using UV-Vis Spectrophotometer (Zhang et al., 2012).

EXPERIMENTAL SECTION
Equipments

A set of  standard glass tools, magnetic stirrer, thermometer, hotplates, 
oven, furnace, vacuum, a separator funnel, X-Ray Diffraction (Rigaku 
Miniflex 600), FT-IR spectrometer (Shimadzu prestige-21) and UV-Vis 
spectrophotometer (Thermo Scientific Geneysis 20) were used in this ex-
periment. 

Materials
Chemicals to be used in this study such as sodium metasilicate (Na-

2
SiO

3
), sodium tungstat (Na

2
WO

4
), potassium hydroxide (KOH), po-

tassium chloride (KCl), sodium hydroxide (NaOH), sodium carbonate 
(Na

2
CO

3
), magnesium nitrate (Mg(NO

3
)
2
), aluminum nitrate (Al(NO

3
)
3
), 

procion red (C
15

H
15

N
3
O

2
) and water. Water was supplied from Intergrat-

ed Research Laboratory, Sriwijaya University using Puriteâ water filtration 
systems. 

Procedure
The synthesis of  layered double hydroxides

Double layer synthesized on hydroxy solution with the concentration 
of  each 50 mL of  Mg(NO

3
)
2
 1 M and 20 mL of  Al(NO

3
)
3
 1 M added to 

250 mL of  water and then stirred. pH of  solution was adjusted to 10 using 
NaOH and heated to the temperature of  40 oC. The reaction was kept at 
a pH value of  10 then added with 20 mL of  Na

2
CO

3
 2 M and 10 mL of  

NaOH 2 M. The solution was heated to 40 oC for 3 hours and left in the 
oven at a temperature of  70 oC for 40 hours. The product obtained in the 
form of  white suspension washed and dried at room temperature. The 
products are characterized by XRD powder analysis and FT-IR.

Synthesis Polyoxometalate K4[α-SiW12O40]•nH2O
Synthesis polyoxometalate K

4
[αSiW

12
O

40
]nH

2
O synthesized by dis-

solving sodium metasilicate as many as 11 g in 100 mL of  water used as A 

mailto:intandevanan08@gmail.com


Sari et al. 2017/Science & Technology Indonesia 2 (3) 2017:71-75

© 2017 Published under the term of  the CC BY NC SA 4.0 license 72

solution of  as many as 182 g of  sodium tungstat dissolved in 300 mL of  
hot water and a solution of  the foundation of  the solution b. as much as 
165 mL of  HCl 4 m added drops demi drops for 5 min with stirring with 
300 rpm speed to dissolve deposits of  tungstat acid. Then, quickly added 
solution A into the solution B with the addition of  50 mL followed hydro-
chloric acid 4 M. The solution is kept for 1 hour at a temperature of  100 
oC to the value of  pH 5 to 6. As many as 50 mL and 80 mL sodium tung-
stat hydrochloric acid 4 M is added into the solution quickly. This solution 
is difiltrasi after it is cooled at room temperature. The solution used to 
obtain salt or acid [α-SiW

12
O

40
]4-.nH

2
O. The potassium salt is obtained by 

adjusting the pH value of  the solution at 2 using potassium chloride by as 
much as 50 g quickly to white from salt deposits acquired potassium form 
K

4
[α-SiW

12
O

40
].nH

2
O Characterization of  compound was done using FT-

IR spectroscopy and XRD analysis. 

Preparation of  Layered Double Hydroxides Pillared Polyoxometalate 
K4[αSiW12O40]•nH2O

The process pillarization of  layered double hydroxides by polyoxome-
talate was conducted using ion exchange method. Reactions is done by 
making the solution A, polyoxometalate K

4
[α-SiW

12
O

40
].nH

2
O as much as 

1 g with 50 mL water 100 mL in beaker and solution B, 1 g of  double layer 
in hydroxides was placed into beaker and added 25 mL of  1 M sodium hy-
droxide. Solution A and solution B was mixied together in one neck round 
bottom flask with the stirring speed 280 rpm in irrigated conditions gas N

2
 

in order not going direct contact with oxygen in the air while using mag-
netic stirring in stirer with variations in time. The determination of  the 
variation of  time starting from 3, 6, 9, 12, 24, 36, and 48 hours. This sus-
pension is cooled and washed with water and dried at room temperature. 
Characterization was performed using XRD powder and FT-IR analyses. 
Application of  Pillared Material as Adsorbent of  Procion Red 

Effect of  Adsorption Time
As much as 2 g pillared material was mixed with 50 mL of  procion 

red with concentration concentration of  25 mg/L. The mixture is then 
stirred using a horizontal shaker at the appointed time. As control, in a 
different container as much as 2 grams of  non pillared material was ap-
plied. Variation of  time was 10, 20, 30, 40, 50, 60, 70, 80 and 90 minutes. 
Procion red and adsorbent was separated by filtration then concentration 
was measured by using UV-Vis spectrophotometer. Adsorption rate can 
be calculated using equation (1). 

Effect of  Concentration and Temperature Adsorption
Influence of  thermodynamic adsorption of  procion red adsorption on 

pillared material was done through a series of  experiments by varying the 
concentration of  procion red and temperature. As much as 2 g of  adsor-
bent was mixed with 50 mL of  solution of  procion red (10, 25, 50, 100 
mg/L) while stirring using a horizontal shaker for 1 hour at a temperature 
that varies (30, 40, 50, 60, 70, and 80 oC). As control, in a different con-
tainer as much as 2 g of  layer double hydroxides was interacted with 50 
mL of  procion red substances (10, 25, 50, 100 mg/L). The mixture was 
filtered, then a solution of  procion red which has been separated from 
the adsorbent was measured using a UV-Vis spectrophotometer to know 
the concentration of  residual concentration of  procion red. Adsorption 

capacity and energy can be calculated using the equation of  Langmuir in 
equations (2) and (3), whereas the entropy and enthalpy adsorption can be 
calculated using equation (4). 
 
Data Analysis

The pillared layer double hydroxides was characterized using FT-IR 
and XRD analyses. Basal spasing value can be obtained based on XRD 
pattern and it is expected that the pillared material has a layer between 
layers larger than before the process of  pillarization. Pillared material was 
used as adsorbent of  procion red. The adsorption process was studied 
through kinetic and thermodynamic parameters. The adsorption kinetic 
was studied by variation of  adsorption time and adsorption rate calculated 
based on Langmuir Heinselwood adsorption equation as follows:

1
ln( )oCC tk K

C C
= +        (1)

where:
C0 = the initial concentrations procion red
C = concentrate procionred after time
t = adsorption time
K = adsorption equilibrium constant

 The thermodynamic parameters were studied through varia-
tions in the concentration of  procion red dye and temperature. Adsorp-
tion capacity and energy were calculated on the basis of  the Langmuir 
equation as follows:

1C C
m bK b
= +        (2)

lnE RT K= −         (3)

where:
C    =  procion red concentration after adsorption reaches equilibri-
um
m = mol of  procion red adsorbed at 0.5 grams adsorbent
K = equilibrium constant
b = adsorption capacity
E = adsorption energy 
R = constant
T = temperature

While to find the value of  coefficient of  adsorbat distribution used equa-
tion as follows:

ln
S H

Kd
R RT
∆ ∆

= −       (4)

where:
Kd = coefficient of  adsorbate distribution (qe/Ce)
ΔH = enthalpy
ΔS = entropy
R = constant
T = temperature

Figure 1. FTIR spectra of  layer double hydroxides. Figure 2. FTIR spectra of  polyoxometalate K
4
[α-SiW

12
O

40
].nH

2
O.

Wavenumber (1/cm) wavenumber (1/cm)



Sari et al. 2017/Science & Technology Indonesia 2 (3) 2017:71-75

© 2017 Published under the term of  the CC BY NC SA 4.0 license 73

RESULTS AND DISCUSSION
Characterization of  Layer Double Hydroxides and Pillared 
Layer Double Hydroxides with Polyoxometalate Using FT-
IR spectrophotometer

Characterization using FT-IR spectrophotometer resulted in IR spec-
trum of  layer double hydroxides and pillared layer double hydroxides at 
various temperatures as seen in Figure 1, 2, and 3. It can be seen in Figure 
1 that the broad vibration peak between the wavenumber 3800-3300 cm-1 
is assigned as the vibration of  the OH group in the structure of  the layer 
double hydroxides (Zvezdova, 2014). The peak at the wavenumber 1635 
cm-1 is a bending of   OH vibration. The wavenumber at 1381 cm-1 is as-
signed as vibration of   stretching of   nitrate. Bending vibration of  nitrate 
was also detected at wavenumber 671 cm-1. Vibration of  Al-O and Mg-O 
were appeared at wavenumbers 601 cm-1 and 408 cm-1.

FTIR spectrum of  polyoxometalate K
4
[α-SiW

12
O

40
].nH

2
O as shown in 

Figure 2 shows the unique vibration of  Si-O at 925.83 cm-1. The vibration 
of  W = O was detected at 979.84 cm-1. The wavenumber at  879.54 cm-1 
shows the presence of  oxygen W-Oe-W vibrations located on the edge 
of  the polyoxsometalate K

4
[α-SiW

12
O

40
].nH

2
O. Peak at 779.24 cm-1 shows 

the vibration of  the W-Oc-W group, where an oxygen atom located at the 
center of  the polyoxometalate K

4
[α-SiW

12
O

40
].nH

2
O compound. 

The double layer hydroxide was then pillarized with a poloxometalate 
K

4
[α-SiW

12
O

40
].nH

2
O by an aqueous solution wherein the double layer 

hydroxides was dissolved with NaOH and the polyoxometalate K
4
[α-Si-

W
12

O
40

].nH
2
O was dissolved with water.  The weight ratio of  layer double 

hydroxides: polyoxometalate K
4
[α-SiW

12
O

40
].nH

2
O was 1: 1. Variation of  

pillarization time was 3, 6, 9, 12, 24, 36 and 48 hours. The FTIR spectrum 

of  layer double hydroxides pillared with polyoxometalate K
4
[α-SiW

12
O

40
].

nH
2
O compound was shown in Figure 3.
FTIR spectrum in Figure 3 showed that almost vibrations are simi-

lar at various pillarization times. Pillarization at 3-24 hours give dominant 
vibration of  layer double hydroxides, while pillarization at 36-48 hours 
resulted almost IR spectrum of  polyoxometalate K

4
[α-SiW

12
O

40
].nH

2
O. 

Due to unclear results to determine optimal pillarization process, further 
characterization was conducted using XRD powder analysis. 

Characterization of  Pillared Layer Double Hydroxides Using 
XRD Powder Analysis. 

The XRD powder pattens of  layer double hydroxides pillared with 
polyoxometalate K

4
[α-SiW

12
O

40
].nH

2
O at various time was  shown in 

Figure 4. The variation of  pilaration time is expected to obtain the best 
diffraction showing the diffraction of  a pillared polyoxometalate K

4
[α-Si-

W
12

O
40

].nH
2
O to layer double hydroxides. Diffraction of  polyoxometa-

late at 6-10°, 15-20°, 22-25°, and 35-40° is emphasized to determine the 
successful pilarization process Yang et al (2011). On the other hand, dif-
fraction of  layer double hydroxides at 10o and 60o is not affected to the 
pillarization process (Dolidovich and Palkovits, 2015; Shan et.al, 2014). 
Diffraction at of  60o indicating that the presence of  anions on the inter-
layer may be anion nitrate, carbonate, or other anions (Kuang et.al, 2010; 
Aviles et.al, 2015).

The XRD patterns of  pillarization at 3 hours, 6 hours and 9 hours 
showed there was a peak at an angle of  6-10o with a small intensity. 
Whereas in the 12 hours pillarization shows characteristic of  the pillarized 
polyoxometalate K

4
[α-SiW

12
O

40
].nH

2
O at the diffraction angle 8.5o with 

Figure 3. FT-IR spectrum of  layered double hydroxides pillared with 
polyoxometalate K

4
[α-SiW

12
O

40
].nH

2
O at 3 hours (a) ,6 hours (b), 9 

hours (c), 12 hours (d), 24 hours (e), 36 hours (f) and 48 hours (g). 

Figure 4. XRD powder patterns of   layer double hydroxides pillared 
with polyoxometalate K

4
[α-SiW

12
O

40
].nH

2
O  at 3 hours (a), 6 hours (b), 9 

hours (c), 12 hours (d), 24 hours (e), 36 hours (f), and 48 hours (g).

Figure 5.  Effect of  procion red adsorption time using layer double hydroxide and pillared layer double hydroxides at 12 hours. 

Wavenumber (1/cm)
Diffraction Angel (degree)



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© 2017 Published under the term of  the CC BY NC SA 4.0 license 74

a intensity of  353.5. Pillarization time at 36 hours and 48 hours showed 
that there is no peak in the region of  6-10° which is characteristic of  the 
K

4
[α-SiW

12
O

40
].nH

2
O.

From this diffraction data, it can be seen that the 12 hours pillarization 
time has a diffraction angle of  6, 10, 35 and 40° which is characteristic 
of  layer double hydroxides pillared compound. Other pillarization time 
at  3 hours, 6 hours, 9 hours, 24 hours, 36 hours and 48 hours does not 
show any diffraction at 6°. Thus, the optimal pillarization of  layer double 
hydroxides with polyoxometalate K

4
[α-SiW

12
O

40
].nH

2
O was achieved at 12 

hours. Futher experiment was used layer double hydroxides pillared poly-
oxometalate K

4
[α-SiW

12
O

40
].nH

2
O at 12 hours as adsorbent of  procion 

red dye in aqueous medium. 

Effect of  Adsorption Time on Adsorption of  Procion Red 
Using Layer Double Hydroxides and Pillared Material

Layer double hydroxides pillared with polyoxometalate K
4
[α-SiW

12
O

40
].

nH
2
O can absorb more adsorbate than double layer hydroxide material at 

the same time as shown in Figure 5. The optimum absorption occurs in 
the layer double hydroxides as control which absorbs the procion red dye 
shown by the blue curve at 50 minutes with absorption of  32.69 ppm 
from the initial concentration of  60 ppm. On the other hand, adsorption 
of  pillared material reached more than 70 ppm at the same time with layer 
double hydroxides. The adsorption patterns of  layer double hydroxides 
and pillared material have similar style. Adsorption was slow at initial time 
and reach equilibrium at around 70 minutes. Layer double hydroxides pil-
lared polyoxometalate K

4
[α-SiW

12
O

40
].nH

2
O  compound showed the opti-

mum adsorption at 20 minutes with adsorption of  57.45 ppm from initial 
concentration of  100 ppm.  By increasing adsorption time will increase 
the amount procion red adsorbed. Adsorption was almost constant at 50 
minutes. Both physisorption and chemisorption will give similar trend for 
adsorption by increasing adsorption time (Yu, et al., 2015). 

The data was obtained in Table 1 show that layer double hydroxides 
pillared with K

4
[α-SiW

12
O

40
].nH

2
O  has adsorption rate faster than adsor-

bent before pillarization. Probably due to of  layer activity after pillariza-
tion can create reactivity of  pillared layer double hydroxides. 

Effect of  Concentration and Temperature Adsorption of  
Procion Red Using Layer Double Hydroxides and Pillared 
Material as Adsorbent. 

Figure 6 and 7 show the effect of  temperature and concentration of  
procion red on layer double hydroxides and pillared material. These results 
in general shows that the higher the temperature can create the greater 

of  procio red adsorbed. The greater concentration of  procion red also 
will increase the amount of  procion red adsorbed. These phenomena was 
equal for both layer double hydroxides as adsorbent as shown in Figure 
6 and layer double hydroxides pillared K

4
[α-SiW

12
O

40
].nH

2
O  as shown in 

Figure 7.
Figure 6 and 7 shows that there is an adjacent point at the concentra-

tion of  procion red 10 mg/L and 20 mg/L due to increasing termperature 
did not increased the adsorption of  procion red. The highest adsorption 
was reached at temperature 70 oC for both layer double hydroxides and 
pillared material. By increasing concentration of  procion red was also in-
creased the adsorption of  procion red but at concentration 30 and 50 oC 
there was a path of  adsorption on pillared layer double hydroxides. Prob-
ably due to interlayer activity caused unstability of  pillared layer double 
hydroxides. 

The adsorption capacity and energy of  the procion red dye adsorp-
tion on layer double hydroxides and pillared layer double hydroxides were 
obtained from equation 2-4 and the results are presented in Table 2. In 
general, adsorption capacity and energy were increased by increasing tem-
perature (Vimoses et al, 2009). In contrast, adsorption capacity of  procion 
red on pillared layer double hydroxides was lower than layer double hy-
droxides. This phenomena is due to unstable pillared layer double hydrox-
ides toward procion red and also molecular size of  procion red is larger 
than interlayer distance material after pillarization. 

The further thermodynamic parameters are enthalpy (ΔH) and entropy 
(ΔS) of  the procion red dye adsorption on layer double hydroxides and 
pillared material as shown in Table 3. The thermodynamic parameter in 
Table 3 showed that irregular data. As explained above due to unstable 
pillared layer double hydroxides toward procion red dye caused enthalpy 
and entropy can be predicted by increasing temperature and concentration 
of  procion red. 

Figure 6. Effect of  temperature and concentration of  procion red on 
layer double hydroxides Figure 7. Effect of  temperature and concentration of  procion red on 

layer double hydroxides pillared K
4
[α-SiW

12
O

40
].nH

2
O

Table 2. Adsorption capacity and energy of  procion red dye on layer dou-
ble hydroxides and pillared material. 

Adsorbent
Temp. 
(oC)

b (mg/g)
E 

(kJ/mol)

Layer double 
hydroxides

30 28.5 9.04

40 27.02 8.69

50 90.90 11.07

60 111 11.13

70 125 10.8

Pillared 

30 41.1 18.5

40 46.7 15.3
50 16.8 10.9

60 2.99 2.95

70 16.8 1.59

Tabel 1. The adsorption rate of  procion red on layer double hydroxides 
and pillared material. 

Adsorbent 
Parameter

k
1 
(minutes-1) R2

Layer double hydroxides 0.302 0.666
Pillared 0.523 0.569



Sari et al. 2017/Science & Technology Indonesia 2 (3) 2017:71-75

© 2017 Published under the term of  the CC BY NC SA 4.0 license 75

Table 3. The enthalpy value (ΔH) and entropy (ΔS) of  procion red dye 
adsorption on layerv double hydroxides and pillared material

Adsorbent Co R2 ΔH (kJ/mol) ΔS (kJ/mol)

Layer double 
hydroxides

20 0.821 -5004 182.2

30 0.948 -3505 123.7

40 0.957 -2536 93

50 0.948 -2994 107
60 0.972 -2260 79.79

Pillared 

20 0.048 -4461 0.136

30 0.946 -2689 99.1

40 0.929 -1363 50.87

50 0.990 -1215 46.25
60 0.848 -1399 49.82

CONCLUSSIONS
Pillared layer double hydroxides with K

4
[α-SiW

12
O

40
]•nH

2
O was suc-

cessfully conducted, which was identified from XRD analysis. XRD pat-
terns showed optimal pillarizationresults at 12 hours by indicating the 
presence of  double layer hydroxy material at 60, 100, and 350 diffraction an-
gles and in regions 60 – 630 indicated the existence of  pillarization process. 
The optimum adsorption of  procion red was occurred at 20 minutes with 
adsorption of  57.45 ppm from initial concentration of  100 ppm. Procion 
red adsorption using pillarized compound resulted in adsorption rate (k) 
of  0.523 min-1, while the influence of  temperature and concentration of  
adsorption capacity is greatest at temperature 70 oC. The largest adsorp-
tion energy at 70oC is 125 kJ/mol, and for entropy (ΔS) and enthalpy (ΔH) 
decreases with increase of  dye concentration.

ACKNOWLEDGEMENT
Authors thank to Sriwijaya University for support of  this research through 
“Hibah Profesi 2017 to A.L. 

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