Water Air Soil Pollut (2016) 227:134
DOI 10.1007/s11270-016-2834-y
Treatability of Methylene Blue Solution by Adsorption Process
Using Neobalanocarpus hepmii and Capsicum annuum
Risky Ayu Kristanti &
Mohamad Khairul Ariffin Kamisan &
Tony Hadibarata
Received: 30 December 2015 / Accepted: 28 March 2016
# Springer International Publishing Switzerland 2016
Abstract The effectiveness of adsorbent agent from agricultural wastes and biomass to remove dye from aqueous solution was investigated. In this study, solution of
methylene blue (MB) and two adsorbents, bark of cengal
tree (Neobalanocarpus hepmii) and seed of red chili
(Capsicum annuum), were tested. Experiments were performed with testing MB solution at 3-h interval and also
testing with different quantities of adsorbent. In addition,
the further study on characterization of adsorbent by Field
Emission Scanning Electron Microscopy (FESEM) and
Fourier Transform Infrared Spectroscopy (FTIR) was
conducted in order to elucidate the properties and surface
structure of the adsorbents. Analysis from UV-Vis spectroscopy showed that both adsorbents remove MB dye
effectively and according to FESEM analysis due to the
structure of the adsorbent were perforated and consist of
polymer components. On the other hand, in FTIR perspective, the adsorption was successful because of the
R. A. Kristanti
Faculty of Engineering Technology, Universiti Malaysia Pahang,
Lebuhraya Tun Razak, Gambang, 26300 Kuantan, Malaysia
M. K. A. Kamisan : T. Hadibarata (*)
Centre for Environmental Sustainability and Water Security
(IPASA), Research Institute for Sustainable Environment,
Universiti Teknologi Malaysia, 81310 UTM, Skudai, Johor,
Malaysia
e-mail: [email protected]
M. K. A. Kamisan : T. Hadibarata
Department of Environmental Engineering, Faculty of Civil
Engineering, Universiti Teknologi Malaysia, 81310 UTM, Skudai,
Johor, Malaysia
presence of carboxyl and carbonyl groups from both
adsorbent that helps enhanced the process of adsorption.
Keywords Methylene blue . Dye removal . Adsorption .
Agricultural waste
1 Introduction
Since dyeing technology has been discovered, the increased in number of the dye application for industries
such as rubber, plastic, textile, paper, leather, and food has
led to their presence in the water environment (Buthelezi
et al. 2012; Karacetin et al. 2014). The colorization
process that require high amount of water has generated
the dye wastewater. This wastewater contains mixture of
natural and synthetic dye including azo, methane, nitro,
and carbonyl that recalcitrant to the degradation (Syafalni
et al. 2012). Methylene blue (MB) are high-volumeproduction commercial dye widely used in coloring paper, temporary hair colorant, dyeing cottons, wools, coating for paper stock, etc. (Kumar and Kumaran 2005; Han
et al. 2006). Owing to its mass production, widespread
use, and mass disposal, a large amount of methylene blue
ends up to aquatic environment by various sources and
pathways (Kumar and Kumaran 2005). The toxicity and
low biodegradability of MB have well documented, and
there are many adverse health effects resulted such as
vomiting, diarrhea, gastritis, eye burns, headache, and
chest pain (Hameed et al. 2007; Erdem et al. 2005).
Moreover, the colored effluents often suffocate aquatic
organisms to death once it entraps them (Crini 2006).
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Page 2 of 7
An effective and efficient dye water treatment is of
must interest in order to eliminate the environmental
threat addressed by the dye application. So far, there
are plenty treatment methods and techniques existed to
remove the dye molecules, including electrochemical
methods, ion-exchange, coagulation-flocculation, ozonation, adsorption, and microorganisms (Hadibarata et al.
2013; Hadibarata and Kristanti 2013; Rangabhashiyam
et al. 2013) but adsorption method has been preferable
since it showed the most effective method to remove
dye. The process includes adsorbent materials that consist of activated carbon that is not low cost and limited at
certain dye. Thus, the screening of novel adsorbent as
activated carbon alternative is needed.
The numbers of researches have demonstrated the
process of dye removal from wastewater by means of
adsorption process (Demiral et al. 2008; Salleh et al.
2011; Kumar et al. 2013; Karacetin et al. 2014). There
are three by-products during the adsorption process such
as polymeric adsorbents, activated carbon, and carbonaceous adsorbents. From all the alternatives adsorbent,
the widely used applicable method for removing dye is
activated carbon (Bernardin 1985). Activated carbon
has not only shown the ability to remove various types
of dyes but also eliminated the broad range of pollutants
such as metal ions, phenols, detergents, pesticides, chlorinated hydrocarbons, PCBs, and other taste- and odorproducing compounds (Gupta and Suhas 2009).
However, the activated carbon high cost tends to increase the cost of adsorption systems (Kapdan et al.
2000 and Porter et al. 1999). Searching an abundant
sorbent material that can serve as viable alternatives to
activated carbon is necessary.
The application of carbonaceous raw materials from
agricultural wastes that have been intensively utilized
including sugarcane bagasse, empty fruit bunch, coir
pith, banana pith, date pits, sago waste, silk cotton hull,
corn cob, maize cob, straw, rice husk, rice hulls, fruit
stones, nutshells, pinewood, sawdust, coconut tree sawdust, bamboo, cassava peel, orange peel, spent tea
leaves, jackfruit peels, rambutan peels, and mangosteen
peels (Lazim et al. 2015; Nor et al. 2015;
Rangabhashiyam et al. 2013; Wirasnita et al. 2015).
This utilization has possibly extended to other waste.
Bark of cengal and seed of chili are also agricultural
solid wastes that can be an alternative and favorable
sorbent materials for the removal of pollutants such as
dyes from aqueous solution that are suitable for application in small industries and developing countries.
Water Air Soil Pollut (2016) 227:134
However, no information is available in the literature
for reactive dye particle, MB, and sorption from aqueous solutions. The present study was specifically aimed
to investigate the role of plant–source adsorbent from
bark from cengal tree and chili seed for treating MB
removal from aqueous solution. Effective variables on
adsorption process performance such as quantities of
adsorbent and adsorption time removal of MB were
examined.
2 Research Methodology
2.1 Adsorbent Preparation
Two agricultural wastes were used in this study, including seed of red chili (Capsicum annuum), and bark from
cengal tree (Neobalanocarpus hepmii). All materials
were washed and cut into small pieces, dried at oven
105 °C for 24–48 h, and grounded into fine powder and
used as adsorbent.
2.2 Dye Solution Preparation
Methylene blue (MB) was purchased from SigmaAldrich, Malaysia. Stock solutions (1000 mg L−1) were
prepared by dissolving 1 g of dye powder with 1000 mL
distilled water and were kept at room temperature until
used for experiment. The chemical structure of MB is
shown in Fig. 1.
2.3 Effect of Concentration and Contact Time
on Adsorption
All working solutions of MB were made by adding
certain amount of deionized water into the stock solution to reach the desired concentration. In each adsorption study, fresh dilutions were used. Experiment were
conducted under the batch conditions in 100-mL
Erlenmeyer flask, using 50-mL dye solution and adsorbent dosage of 1, 3, 5, 7, and 10 g. Flasks were stirred at
25 °C under 120 rpm. Solids from solutions were
Fig. 1 Chemical structure of methylene blue (MB)
Water Air Soil Pollut (2016) 227:134
Page 3 of 7 134
removed directly through a filtration size of 0.45 μm
regenerated cellulose membrane filter (Agilent
Technologies, Germany). Meanwhile, in order to analyze the pattern and accuracy of dye removal, monitoring of dye removal was performed by taking samples in
the defined intervals 3 h until 24 h.
2.4 Adsorption Experiment
The batch adsorption ability tests were operated in triplicate following the consistent experiments: 5 g of adsorbent was mixed with 50 mL of dye solutions
(1000 mg L−1) in 100-mL conical flask. The conical
flask was then covered by aluminum foil. Thereafter, all
flasks were put in orbital shaker at 25 °C under 120-rpm
shaking speed for 12 h until reaching equilibrium.
Before analysis, the samples were filtered and the supernatant fraction was diluted by ten times and subjected
to UV-Vis spectroscopy (MACHEREY-NAGEL
Spectrophotometers NANOCOLOR® VIS/
NANOCOLOR® UV/VIS) to determine the concentration of dyes remained. The removal rate (%) and adsorption capacity (mg/g) were determined from Eqs. (1)
and (2), respectively:
Removal rateð%Þ ¼
C o −C x
100
Co
ð1Þ
3 Results and Discussion
3.1 Effect of Adsorbent Concentration on Adsorption
The efficiency of adsorption process at concentration of
1, 3, 5, 7, and 10 g adsorbent is shown in Fig. 2. The
removal rates of adsorbents, cengal bark and chili seed,
were slightly increased as dosage of adsorbent increased
(Fig. 2a). One gram of bark dosage have resulted
99.50 % of MB removal. Meanwhile, 3 and 5 g of bark
dosage exhibited 99.80 and 99.84 % of MB removal,
respectively. At the concentration of 1, 3, and 5 g of
chili, the removal rate of MB was 97.23, 97.96, and
98.02 %, respectively. Hence, application of 5 g adsorbent gave the most promising result, and moreover, it
was the most suitable quantity to be applied to treat MB.
It was found that under the concentration of 7 and 10 g
of adsorbents, the efficiency could not be observed since
MB completely adsorbed during the filtration process
(data are not shown). Thus, the concentrations of 7 and
10 g were omitted.
On the other hand, the results of adsorption capacity were different between two adsorbents, as
shown in Fig. 2b. As the adsorbent dosage was
increased, the adsorption capacities of cengal and
chili were decreased. When 1 g of bark dosage
120
where C0 (mg/L) and Cx (mg/L) are, respectively, the
initial and equilibrium MB concentrations in the solution, V (L) is the solution volume, and M (g) is the mass
of adsorbent.
2.5 Adsorbent Characterization
The surface texture and morphology of the sample of
raw adsorbent and sample of adsorbent after decolorization were characterized using field emission scanning
electron microscopy (FESEM, JEOL 6335f-SEM,
Japan). Fourier transform infrared spectroscopy (FTIR)
characterization was carried out for an analysis of functional groups existing on the surface of adsorbent before
and after decolorization. FTIR spectra were recorded in
the range of 400–4000 cm−1 by Spectrum One (Perkin
Elmer, USA).
Removal rate (%)
ð2Þ
A
100
80
60
40
20
0
60
Adsorption capacity (mg/g)
C o −C x
V
Adsorption capacityðmg=gÞ ¼
M
50
1
3
B
5
Cengal Bark
Chili Seed
40
30
20
10
0
1
3
5
Adsorbent dosage (g)
Fig. 2 Removal rate of MB (a) and adsorption capacity (b) at
different dosage of adsorbents
134
Water Air Soil Pollut (2016) 227:134
Page 4 of 7
was applied, the adsorption capacity was 49.75 mg/
g, whereas 3 and 5 g of bark exhibited the adsorption capacity of 16.63 and 9.98 mg/g, respectively.
For chili, adsorption capacity were slightly lower
compared to cengal. When 1 g of seed dosage was
applied, the adsorption capacity was 48.62 mg/g,
then decreased to 16.33 and 9.80 mg/g after 3 and
5 g of chili dosage were added, respectively.
3.2 Effect of Adsorbent Contact Time on Adsorption
The effect of adsorption contact time on the dye removal
is shown in Fig. 3. The removal rate and adsorption
capacity of both adsorbents slightly increased or
remained the same over time. The removal rate of cengal
bark have reached 99.97 % after the first 3 h and remain
stable until 24 h, whereas chili seed have achieved
93.16 % MB removal after first 3 h and slightly increased every 3 h until it reached to 95.21 % in the
end of experiment. In concomitant, the adsorption capacity of chili adsorbents ranged at 9.32 to 9.52 mg/g,
while cengal constantly at 10 mg/g. The removal rate of
MB by cengal bark were highly noted to not changed
120
A
Removal rate (%)
110
100
90
80
70
60
Adsorption capacity (mg/g)
50
0
11
5
10
15
20
25
B
10
9
8
7
Cengal Bark
6
5
after the first 3 h due to the saturation condition of the
adsorbents that has reached equilibrium stage (Demiral
et al. 2008).
3.3 Adsorption Characteristic
3.3.1 FESM
Figure 4 displays the FESEM analysis on surface texture
and morphology of two adsorbents before and after
decolorized dye. Figure 4a shows that bark has a perforated surface structure. When we look at a different
angle, it shows clearly the surface structures of raw
cengal bark made up by cellulose, hemicellulose, and
lignin. These results are also reported by Bernardin
(1985). Moreover, it also stated that polymeric adsorbents was found to be one of the major product alternatives adsorbent existed for an adsorption application
(Bernardin 1985). The availability of polymer in adsorbents improves the performance of adsorbent for trapping the dye particles resulted in the removal of dye
particles from the aqueous solution. After the adsorption
of MB, FESEM results shows MB were trapped inside
the pores and between the cellulose and hemicellulose
(Fig. 4b). On the other hand, other polymer component,
lignin, acts as glue of the dye particles. Thus, the importances of pores and polymer component have been
proven by trapping the dye particles while treating contaminated water.
Figure 4c shows that chili seed has a visible pore
without the presence of polymer components. Figure 4c
displays a large number of pores, deeper rather than
pores of cengal bark. However, large number of pores
obtained in the chili seed did not able to enhance the
chili ability to trap more amounts of the dye particles
than cengal bark. After adsorption process, pores have
been filled up by MB (Fig. 4d) and remain the same.
This might be due to pores has been saturated with MB,
resulting in lower removal ability and adsorption capacity of chili seed compared with cengal bark. The results
were similar with Chen et al. (2011), who conducted
experiment on MB removal using raw lawny grass. It
was found that the large pores and increased surface area
are important factors to enhance uptakes of MB.
Chili Seed
0
5
10
15
20
25
3.3.2 FTIR
Time (h)
Fig. 3 Removal rate of MB (a) and adsorption capacity (b) of two
adsorbents at different contact time
Table 1 shows the FTIR spectrum of bark of cengal and
seed of chili. In Table 1, adsorption peaks were highly
Water Air Soil Pollut (2016) 227:134
Page 5 of 7 134
Fig. 4 FESEM of cengal bark and chili seed for raw sample (a, c) and seed after decolorized MB (b, d), respectively
obtained indicating broad range functional group of
chemical exists. Strong and broad band peak were obtained at 3417.13 cm−1 that assigned to the existence of
functional group of O–H stretch such as alcohols. Peak
at 2928.52 cm−1 was indicated as the present of alkanes
with C–H stretch, and at 1621.60 cm−1, there are
assigned as the functional group of amines with N–H
bend stretch, whereas at 1320.97 cm−1, nitro compound
with N–O asymmetric stretch exists. Alcohols, carboxylic acids, esters, or esters which has C–O stretch was
also found at peak 1033.47 cm −1 and peak at
540.19 cm−1 that represented the alkyl halides group
which has C–Br stretch (Socrates 2004; Nakamoto
2009; Larkin 2011).
After decolorization, the exhibition of the peak at
the 3694.26 cm−1 was caused by the presence of
functional group of alcohols which have O–H stretch.
The exhibition of peak at 2923.87 cm−1 was identified
as group of alkanes with C–H stretch, followed by of
amines with N–H bend stretch at peak 1617.76 cm−1
Table 1 Fourier transform infrared (FTIR) spectroscopy of Neobalanocarpus hepmii and Capsicum annuum before and after MB
adsorption
Absorption frequency (cm−1) of
Neobalanocarpus hepmii
Before
adsorption MB
After
adsorption MB
3417.13
3694.26
Assignment
Absorption frequency (cm−1) of
Capsicum annuum
Before
adsorption MB
O–H stretch, H bounded 3354.92
Assignment
After
adsorption MB
3008.92
O–H stretch, H bounded
2928.52
2923.87
C–H stretch
2928.56
2926.64
C–H stretch
1621.60
1617.76
N–H bend
1740.09
1745.16
C = O stretch
1320.97
1511.39
N–O asymmetric stretch 1650.36
1648.15
C = O stretch
1444.09
1458.40
C–C stretch
709.36
721.37
C–Cl stretch
1033.47
540.19
1033.29
538.55
C–O stretch
C–Br stretch
134
Water Air Soil Pollut (2016) 227:134
Page 6 of 7
and nitro compound with N–O asymmetric stretch at
1511.39 cm − 1 , while the peak observed at
1033.29 cm−1 was assigned to functional group of
alcohols, carboxylic acid ester, and ethers with C–O
stretch. Band at 538.55 cm−1 have proven to the
existence of alkyl halides with C–Br stretch.
The infrared spectrum for chili seed sample before and after the decolorization of MB is shown in
Table 1. In Table 1, adsorption peaks for chili raw
sample were highly obtained indicating broad range
functional group of chemical exists. Strong and
broad band peak were obtained at 3354.92 and
2928.56 cm−1 that assigned to the existence of functional group of O–H stretch and C–H stretch. Peak
at 1740.09 cm−1 was indicated as the present of ester
with C=O stretch and at 1650.36 cm−1, there are
assigned as the functional group of amides with
C=O stretch. Both ester and amides were from the
same general functional group which is carbonyls.
In Fig. 4a, aromatics functional group with C–C
stretch was also found at peak 1444.09 cm−1 and
peak at 709.36 cm−1 that represented the alkyl halides group which has C–Cl stretch (Socrates 2004;
Nakamoto 2009; Larkin 2011).
The infrared spectrum for chili seed after the decolorization of MB shows sharp shape at 3008.92 and
2926.64 cm−1 that assigned to the existence of carboxylic acid with O–H stretch and C–H stretch, respectively. Peak at 1745.16 and 1648.15 cm−1 were indicated as
the present of carbonyls group with ester and amides,
respectively, whereas at 1458.44 cm−1, aromatic compounds with C–C stretch exists. End of peak at
721.37 cm−1, an alkyl halides group with C–Cl stretch
(Larkin 2011; Socrates 2004; Nakamoto 2009).
Functional group existed in the both adsorbents,
bark of cengal tree and seed of chili, had found to be
similar and the presence of alcohols, phenol, carboxylic acid, carbonyl group, and ether help in
binding or trapping MB. The results have shown
the change in functional group member before and
after decolorization of dye particles, indicating that
the functional group plays an important role during
the adsorption (Chang et al. 2012). According the
experimental data for adsorption process, the bark of
cengal and seed of chili were efficient adsorbents for
treating MB. Two adsorbents presented in this study
also a satisfactory adsorption capacity for MB.
Hence, the bark from cengal tree and chili seed, as
raw agricultural materials, might be a potential
adsorbent agent for dye removal especially MB in
aqueous solution.
4 Conclusions
The present study attempts the treatability of MB solution by adsorption process using low-cost adsorbents,
cengal bark and chili seed. Both adsorbents exhibited
more than 99 % of MB removal. The accelerated removal of MB was obtained with the addition of 5 g
adsorbent and was impractical at the addition of concentration at 7 and 10 g. After 24-h adsorption process,
cengal bark and chili seed were filled up by MB to about
10 and 9.52 mg/g, respectively. Through FESEM and
FTIR studies, it is noted that the effectiveness of the
adsorbents were attributed to the presence of great volume and size of pores and broad functional groups such
as carboxylic acids, nitro compounds, and alkyl halides.
Hence, the cengal bark and chili seed might be potential
adsorbents for treating aqueous solution contaminated
with dye particles, especially MB.
Acknowledgments A part of this research was financially supported by a Research University Grant of Universiti Teknologi
Malaysia (Vote No. Q.J130000.2522.10H17).
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