International Journal of Engineering Trends and Technology (IJETT) – Volume 34 Number 5- April 2016
Adsorption of Cadmium and Chromium Ions
from Wastewater by Datura
(DaturaStramonium) fruit
Donadkar D#1, Gour K. *2 & Ranghdale P.K.#3
1 Department of Chemistry, Priyadarshini College of Engineering, Nagpur, India
2 Associate Prof., Department of Chemistry, Priyadarshini J. L. College of Engineering,
846, New Nandanvan, Nagpur-9, India
3 Associate Prof., Department of Chemistry, Bhawabhuti Mahavidyalaya, Amgaon, Nagpur, India
Abstract : This paper describes the adsorption of
chromium and chromium ions from wastewater by
Datura (Datura Stramonium) fruit. The ability of
activated carbon derived from Datura Stramonium
fruit to remove cadmium and chromium ions from
aqueous solutions was investigated. The activated
carbon was produced by using chemical and
physical activation processes. The adsorption
capacity was determined the effect of different
experimental conditions such as pH, contact time,
adsorbent dosage, on the removal of chromium and
Cadmium was studied. Based on the results &
discussions, it can be concluded that the adsorbent
prepared from Datura Stramonium fruit has a
significant capacity for adsorption of Cadmium &
chromium ions from aqueous solution & can be
employed effectively as a low cost adsorbent.
Keywords: Adsorbent, cadmium, Datura Fruit
I. INTRODUCTION
The pollution of water resources due to the
disposal of heavy metals has been on increasing
worldwide concern for last few decades. The
problem of removing pollutants from water and
wastewater has grown with rapid industrialization.
The discharge of toxic meals into water sources is
a serious pollution problem, which may affect the
quality of water supply. Increasing concentrations
of these metals in the water constitute a severe
health hazard mainly due to their non-degradability
and toxicity [1]. Heavy metals are very harmful for
humans, animals and plants. Global and local
agencies have therefore established certain limits
on the quantities of heavy metals being discharged
into environment. Trace metals if transported
towards the ecosystem may enter the human body
through inhalation of dust, consumption of
contaminated drinking water and aquatic livings,
direct ingestion of soil, and consumption of animal
foods and food plants grown in metal-contaminated
soil [2] Many methods have been used to remove
heavy metals from wastewater such as membrane
filtration, coagulation, adsorption, oxidation, ion
ISSN: 2231-5381
exchange, precipitation, etc. However, most of
these techniques are expensive and may only be
suitable in circumstances where the concentrations
of the heavy metal ions are relatively high.
Therefore, there is a need to look into alternatives
to investigate a low-cost method, which is effective
and economical. Adsorption with activated carbon
can also be highly efficient for the removal of
numerous trace elements from water, but the high
cost of activated carbon inhibits its large scale use
as adsorbent [3]. To overcome this difficulty, there
is a strong need to develop cheap adsorbents which
can be used in developing countries. Wastes from
agricultural practices are among natural materials
available in large quantities which may have
potential to be used as low cost adsorbents, as they
represent unused resources widely available and
environmentally friendly [4] . A large number of
plants and their wastes have been used to remove
heavy metals and other contamination from water
all over the world [5]. Recently, considerable
attention has been devoted to develop better and
suitable adsorbents for removal of metal purpose
but adsorption process is the cheapest, simplest,
easily available and accessible process for metal
removal in developing country like India [5].
Materials like coconut shell carbon [6], activated
carbon [7] in the present study, removal of
Cadmium and chromium Ions by adsorption on to
low cost material like thermally activated Datura
Stramonium fruit carbon was investigated.
II. MATERIALS AND METHODS
Preparation of Adsorbent : Datura Stramonium
fruit were collected from the nearby locality and
washed several times with distilled water to
remove dust and other impurities. Then drying, it
was ground using domestic mixer and sieved to
250 mesh size. The sample is washed with distilled
water to remove colour and dried in an oven at
80oC for 24 hours. The dried sample was stored in
airtight bottles for further use without any chemical
or physical treatment.
http://www.ijettjournal.org
Page 220
International Journal of Engineering Trends and Technology (IJETT) – Volume 34 Number 5- April 2016
III. RESULTS AND DISCUSSION
Effect of contact time: The equilibrium time is one
of the most important parameters in the design of
economical wastewater treatment systems [8,9]. In
order to determine equilibrium time for Datura
Stramonium fruit on the adsorption efficiency of
cadmium and chromium ions, we studied to change
of adsorption capacity with time in the cadmium
and chromium concentration of 100 mg/L
(Fig.1). The amount of cadmium and chromium
ion adsorbed at the equilibrium time reflects the
maximum adsorption capacity of the adsorbent
under these particular conditions. The result
showed that the adsorption of metal ion increases
with time up to 1hour and then it becomes almost
constant at the end of the experiment. It can be
concluded that the rate of metal binding with
biomass is more predominant during initial stages,
which gradually decreases and remains almost
constant after 120min. The active adsorption sites
of the adsorbent get involved in metal
complexation as soon as the adsorbent is
introduced into the system.
25
q (mg/g)
20
15
Cr
10
Cd
5
0
0
50
100
150
200
Time (Sec)
Fig 1. Effect of contact time on the adsorption capacity of
pH on the adsorption of metal ions onto Datura
Stramonium fruit was evaluated in the pH range of
2 to 8. The highest removal efficiency for Cd and
Cr adsorption with Datura Stramonium fruit was
obtained at pH6. pH range of 3 to7, the percentage
removal increased rapidly and the removal became
consistent, ranging between 80% and 95%. At
lower pH values, the adsorption efficiency was
found to decrease. The low adsorption of metal
ions at pH 2 was due to high concentration and
high mobility of H+ ions, which competed with
metal ions for the adsorption sites, As the pH
increased, there were fewer H+ ions present in the
solution and consequently more negatively charged
sites were made available and this facilitated
greater metal ions uptake by electrostatic attraction.
q (mg/g)
Reagents : All reagents used in this study were
of analytical grade obtained from Merck Germany.
Stock solution of cadmium (1000 mg/L) was
prepared by dissolving CdSO4 in distilled water
and Stock solution of chromium (1000 mg/L) was
prepared by dissolving K2Cr2O7 in distilled water.
The pH at working solutions was adjusted to
desired values with dilute NaOH and H2SO4 using
a pH meter.
100
90
80
70
60
50
40
30
20
10
0
Cr
Cd
0
5
10
pH
Fig.2. Effect of pH on the removal of chromium by
DaturaStramonium fruit(adsorbent dosage: 2g/L, Cd and Cr: 5
mg/L, temperature: 20oC).
Effect of Adsorbent dose: The effect of biomass
dosage on metal adsorption is shown in Figure3.
The adsorption of metal ions increased with the
adsorbent dosage and at adsorbent dosage above
0.4gm/100ml reached equilibrium. The percentage
of metal removal increased with the increasing
amount of biomass. This may be attributed to the
availability of more and more binding sites for
complexation of metal ions. Further increment in
adsorbent dose did not cause significant
improvement in adsorption. This seems to be due
to the binding of almost all ions to the adsorbent
and equilibrium is reached between the ions bound
to the adsorbent and those remaining unadsorbed in
the solution.
cadmium and chromium by (Datura Stramonium) fruit
(adsorbent dosage : 2g/L, pH: 3, Cd and Cr: 100 mg/L,
temperature: 20oC)
Effect of pH : The pH of aqueous solution plays on
important role in the adsorption capacity. Before
mixing the solution with the adsorbent, we
prepared test solutions with pH values ranging
from 2 to 10 to determine the optimal pH. After we
determined the optimal pH value, we continued to
experiments on this pH (optimal pH) in all
subsequent adsorption tests. The effect of solution
ISSN: 2231-5381
http://www.ijettjournal.org
Page 221
International Journal of Engineering Trends and Technology (IJETT) – Volume 34 Number 5- April 2016
100
90
y = 0.297x + 3.426
R² = 0.928
80
16
q (mg/g)
70
60
14
50
Cr
12
30
Cd
10
Ce /qe
40
20
10
8
6
0
0
0.2
0.4
0.6
4
adsorbent dose (g/l)
2
0
0
Fig.3. Effect of adsorbent dosage on the removal of Cadmium
and chromium by Datura Stramonium fruit (Cr and Cd :
100mg/L, pH: 3, temperature : 20oC).
Equilibrium isotherms : Isotherms are the
equilibrium relations between the concentrations of
the sorbate on the solid phase and the liquid phase
at a constant temperature. In the present study,
equilibrium studies were carried out at pH of 3,
adsorbent dosage of 2 g/L, Cr and Cd
concentration 100 mg/L, temperature of 20oC and
contact time of 90 min. The equilibrium data were
analyzed by the most commonly used isotherms;
Langmuir and Freundlich models.
The Langmuir model assumes that uptake of
sorbate occurs on a homogenous surface by
monolayer sorption without any interaction
between the sorbed ions. Also, all the binding sites
of surface have equal energy of sorption. The
linear form of the Langmuir equation can be given
as:
(1)
Where qe; is the monolayer adsorption capacity
(mg/g), b; is the Langmuir constant (L/mg), Ce; is
equilibrium concentration of sorbate. The plot of
Ce/qe versus Ce was employed to calculate the
intercept value of 1/bqe and slope of 1/qe as shown
in Figure 4 and 5.
10
20
Ce
30
40
Fig.5. The linear plot of Langmuir equilibrium
model for chromium ions
One of the essential characteristics of this model
can be expressed in terms of the dimensionless
constant separation factor for equilibrium
parameter, RL, defined as:
RL 1/ (1 + bC0 ) (2)
The value of RL indicates the type of isotherm to
be irreversible (RL=0), favourable (0<RL˂1).
The Freundlich isotherm, on the other hand,
assumes o heterogeneous sorption surface with
sites that have different energies of sorption. This
model can be presented as:
InqeInK(1/n) × lnCe (3)
whereK; is the relative sorption capacity of sorbent,
and nf; is a constant related to sorption intensity.
The plot of Inqe versus InCe should give a straight
line with a slope of 1/n and intercept of InK as
shown in Figure 6 and 7.
0.6
y = 0.395x - 0.207
R² = 0.968
y = 0.236x + 0.106
R² = 0.844
0.5
0.2
0.4
lnqe
lnqe
0.4
0.6
0.3
0.2
0
0.1
0
0
0
0.5
1
1.5
0.5
1
lnce
1.5
2
2
Fig.6. The linear plot Freundlich equilibrium
model for cadmium
lnce
Fig.4. The linear plot of Langmuir equilibrium
model for cadmium ions
ISSN: 2231-5381
http://www.ijettjournal.org
Page 222
International Journal of Engineering Trends and Technology (IJETT) – Volume 34 Number 5- April 2016
alternative for the elimination of Cadmium and
Chromium ions from wastewater.
0.6
y = 0.236x + 0.106
R² = 0.844
0.5
ACKNOWLEDGEMENTS
One of the author(s) (D. K. Donadkar) is
thankful to the Head, Chemistry Department,
Priyadarshini college of engineering Nagpur, for
providing the necessary laboratory facilities. The
author also thank the concerned authorities of
the NEERI, Nagpur for providing facilities to
carry out this work references
lnqe
0.4
0.3
0.2
0.1
0
0
0.5
1
1.5
2
lnce
REFERENCES
Fig 7. The linear plot Freundlich equilibrium
model for chromium
To evaluate the applicability of Langmuir and
Freundlich isotherm models for the adsorption of
Cadmium and Chromium ions by Datura
Stramonium fruit, all parameters of these models
were calculated and are shown in Table 1.
IV. TABLE 1
Langmuir and Freundlich isotherm models for the adsorption of
Cadmium and Chromium ions by Datura Stramonium fruit
Langmuir
Ions
Cd
Cr
Cd
Cr
b (L/mg)
0.595
0.291
Freundlich
K(mg/g) (mg/L)-1/n
0.2365
0.2074
qmax(mg/g)
R2
3.539
3.357
0.9199
0.9282
N
4.228
2.526
R2
0.8445
0.9681
V. CONCLUSION
The aim of this work was to find the possible use
of Datura Stramonium fruit powder as a sorbent for
the removal of Cadmium and Chromium ions from
aqueous solutions. This paper presented the results
of a detailed study of the adsorption process that
was used for the removal of Cadmium and
Chromium ions from aqueous solutions. According
to experimental results, all operational parameters
studied such as contact time, effect of pH, Effect of
adsorbent dose of sorbent. The results indicate that
the optimum pH for the removal of Cr and Cd ions
by Datura Stramonium fruit is around 3, and
equilibrium conditions for adsorption are attained
nearly in 90 min.[10] The equilibrium data fitted
well with the Langmuir isotherm. The monolayer
sorption capacity of the sorbent was found 100
mg/L by using Langmuir equation. The results
showed that the Datura Stramonium fruit as an ecofriendly and low-cost sorbent might be a suitable
ISSN: 2231-5381
1.
F. Gode, E.D. Atalay, E. Pehlivan, Removal of Cr (VI)
from aqueous solutions using modified red pine sawdust, J.
Hazard Mater. 2008, Vol. 152, 1201-1207.
2. Oliver MA, Soil and Human Health: a review. Eur. J. Soil
Sci. 1997, Vol. 48, 573-592.
3. A. K. Chakravarti, S.B. Chowdhury, S. Chakrabarty, T.
Chakrabarty, D.C. Mukherjee, Liquid membrane multiple
emulsion process of chromium VI separation from
wastewaters, Colloids Surf. A Physicochem. Eng. Aspects
1995, Vol. 59, 103.
4. N.T. Abdel-Ghani, M. Hefny and El-Chaghaby, G.A.F.
Removal of lead from aqueous solution using low cost
abundantly available adsorbents. Int. J. Environ. Sci.
Tech. 2007, Vol. 4 (1), 67-73.
5. S. Kumar, A. Gupta and J. P. Yadav: Fluoride removal by
mixtures of activated carbon prepared from Neem
(Azadirachtaindica) and Kikar (Acacia arabica) leaves.
Ind. J. Chem. Tech., 2007, Vol. 14, 355-361.
6. A. J. Arulanantham, T. V. Ramakrishna and N.
Balasubramanium: Studies on fluoride removal by
coconut shell carbon. Ind. J. Environ. Hlth., 1992, Vol. 12,
531-536.
7. K. Muthukumaran,, N. Balasubramanian and T. V.
Ramakrishna: Removal of fluoride by chemically activated
carbon. Ind. J. Environ. Protect., 1995, Vol. 15, 514-517.
8. D. Mei Zhang, H. Zhang, J. Liu, Adsorption of methyl
violet from aqueous solution by halloysite nanotubes,
Desalination 2011, Vol. 268, 111-116.
9. Hamed M. Jassim, Yousif A. Aziz Kurli, Fakhiri H.
Ibraheem Al.-nidai, Environmental issues in Erbil city,
Internaltional Journal of Engineering Trends and
Technology (IJETT), 2013 Vol. 4 issue 8No5,3509-3515
10. M.Dakiky,A.Khamis,M.M.Manassra Slective adsorption
of Cr(VI)in industrial waste water using low cost
adsorbents,Adv.Environ.Res.2002,Vol6(4),533-540
http://www.ijettjournal.org
Page 223