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Removal of lead from battery manufacturing
wastewater by egg shell
Chumlong Arunlertaree1, Wanvisa Kaewsomboon2,
Acharaporn Kumsopa3, Prayad Pokethitiyook4
and Patra Panyawathanakit5
Abstract
Arunlertaree, C., Kaewsomboon, W., Kumsopa, A., Pokethitiyook, P. and Panyawathanakit, P.
Removal of lead from battery manufacturing wastewater by egg shell
Songklanakarin J. Sci. Technol., 2007, 29(3) : 857-868
This research was carried out to investigate the removal of lead from battery manufacturing waste-
water by egg shells. The effect of operating parameters i.e., initial pH, contact time, types of egg shell and
dose of egg shell were investigated. The characteristics and chemical compositions of egg shells were also
investigated and experimental samples were analyzed using AAS, then the data was statistically processed
using least significant difference at a 95% confidence level (p<0.05).
The results indicated that the optimum pH for lead removal using 4 types of egg shell was at pH 6, but
at this pH final concentration of lead was too low for study of adsorption isotherm. Therefore, unadjusted
pH wastewater was used with an initial lead concentration of about 2.365 mg/L, initial pH of 1.35-1.45.
Unadjusted pH wastewater decreased the use of expensive chemical reagent for adjusting pH and reduced
chemical residues in the environment due to basic properties of egg shell which immediately increased the
pH of solution. The optimum dose of egg shell was 1.0 g/100 ml of wastewater with a contact time of 90
ORIGINAL ARTICLE
1Ph.D. (Fisheries), Asst.Prof., 2M.Sc. (Appropriate Technology for Resources and Environmental Develop-
ment), 3Ph.D. (Biology), Asst.Prof., Program of Appropriate Technology for Resources and Environmental
Development, Faculty of Environment and Resource Studies, Mahidol University, Salaya, Phutthamonthon,
Nakhon Pathom, 73170 Thailand. 4Ph.D. (Engineering), Assoc. Prof., Department of Biology, Faculty of
Science, Mahidol University, Paya Thai, Bangkok, 10400 Thailand. 5M.Sc. (Technology of Environmental
Management), Department of Science Service, Phaya Thai, Bangkok, 10400 Thailand.
Corresponding e-mail : encar@mahidol.ac.th
Received, 17 April 2006 Accepted, 19 January 2007
Songklanakarin J. Sci. Technol.
Vol. 29 No. 3 May - Jun. 2007 858
Removal of lead from battery manufacturing wastewater
Arunlertaree, C., et al.
minutes. The best adsorbent was natural duck egg shell, which had a significant difference from the other
types of egg shell. The final concentration of lead was 0.059 mg/L which was lower than the wastewater
quality standard.
Equilibrium modeling of the adsorption isotherm showed that removal of lead by 4 types of egg shells
were able to be described by the Freundlich model. From this study, precipitation might take part in the
adsorption process, especially at the high doses of egg shell which increased the high final pH of solution.
Finally, the result of the adsorption isotherm demonstrated that the descending lead removal efficiency was
natural duck egg shell, natural hen egg shell, boiled duck egg shell and boiled hen egg shell, respectively.
Key words : lead, egg shell, battery manufacturing, wastewater
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An important source of water pollutants is
industrial discharge water. Most industrial waste-
waters are discharged directly into natural water
systems without proper management process. In
Thailand, lead is one of major pollutants in waste-
water. It is used as a major raw material in battery
Songklanakarin J. Sci. Technol.
Vol. 29 No. 3 May - Jun. 2007 Removal of lead from battery manufacturing wastewater
Arunlertaree, C., et al.
859
manufacturing and wastewater from this industry
can contain high concentration of lead about 0.50-
25.00 mg/L ( Phomun, 2002).
Adsorption is a physico-chemical technique
which involves mass transfer between liquid and
solid phase (Eckenfelder, 1980). This process can
reduce chemical residues. However, the frequently
used sorbent solid is a synthetic resin which is
quite expensive and a non-bio-degradable
substance, so it is more suitable to use agricultural
waste as the adsorbent. For example, egg shell
that has a good adsorptive properties i.e., pore
structure, CaCO3 and protein acid mucopolysac-
charide that can be developed into the adsorbent.
Important functional groups of protein acid
mucopolysaccharide are carboxyl, amine and
sulfate that can bind heavy metal ion to form
ionic bond (Surasen, 2002). Moreover, egg shell
is neutralizing agent, any aqueous solution equili-
brated with egg shell becomes more basic (Brown
and Lemay, 1985) so heavy metal can precipitate
and deposit on egg shell particles.
Other researchers removed lead from
synthetic wastewater but this study removed lead
from battery manufacturing wastewater and there-
fore has the advantage of direct application to real
treatment. The main objectives of this study were;
1) to study the optimum condition for the removal
of lead using natural and boiled hen and duck egg
shell 2) to study lead adsorption isotherm by the
egg shells 3) to compare the removal efficiency
using four types of egg shell. The results will be
the guideline for the removing heavy metal, reduc-
ing chemical residues, decreasing operation cost,
and recycling waste or by-product.
Materials and Methods
Wastewater preparation and wastewater char-
acteristic analysis
Wastewater from the Battery Organization
(Bang Na, Bangkok) was kept in polyethylene
bottle and stored at 4oC in acid condition (pH < 2)
(Pollution Control Department, 1997) for pre-
cipitation at least 1 day. The wastewater character-
istic included pH value, total dissolved solids
(TDS) and total solids (TS) were analyzed accord-
ing to the standard methods. Lead was digested
using nitric acid - hydrochloric acid digestion
methods and its concentration determined by
Atomic Absorption Spectrophotometer (AAS;
GBC 932 Plus) using the standard method (APHA
et al., 1995).
Egg shell preparation
Natural and boiled hen and duck egg shells
were washed with tap water several times then
air-dried and incubated in hot air oven at 40oC for
30 minutes (because protein component in egg
shell can denature at high temperature; > 40oC).
Consequently, egg shells were ground to a powder
in a grinder, and sieved to obtain between 60-100
mesh (0.25-0.104 mm) size particles.
The removal of lead from battery manufactur-
ing wastewater using egg shells
1. The optimum pH value analysis
1.1 The pH values of wastewater were
controlled at 5, 6 and 7 by using 1 M. NaOH.
1.2 100 ml of sample was added into
Erlenmeyer flask and lead concentration was
analyzed. Then 0.05 g of egg shell was added in
each sample and the rotary shaker was adjusted at
200 rpm, 90 minutes.
1.3 Treated wastewater was filtered
through filter paper No.4, then the lead concen-
tration was determined.
2. The optimum contact time analysis
2.1 0.05 g of egg shell was added into
optimum pH wastewater (from step 1) and the
rotary shaker was adjusted at 200 rpm with 30, 60,
90, 120 and 150 minutes.
2.2 Treated wastewater was filtered
through filter paper No.4, then the lead concen-
tration was determined.
3. The optimum dose of egg shell analysis
3.1 100 ml of optimum pH wastewater
was added into Erlenmeyer flask, then lead con-
centration was analyzed.
3.2 0.05, 0.2, 0.5, 1.0 and 1.5 g of egg
shell was added into each sample and the rotary
shaker was adjusted at 200 rpm with optimum
Songklanakarin J. Sci. Technol.
Vol. 29 No. 3 May - Jun. 2007 860
Removal of lead from battery manufacturing wastewater
Arunlertaree, C., et al.
contact time (from step 2).
3.3 Treated wastewater was filtered
through filter paper No.4, then the lead concen-
tration was determined.
Study of adsorption isotherm
Data from step 3 were used to study adsorp-
tion isotherm for determining the best adsorbent.
Langmuir's and Freundlich's adsorption isotherms
are the most commonly used for the description of
the adsorption data (Samuel and Osman, 1987).
Statistical analysis
The removal efficiency (%)
=
(A−B)
A×100
(Kosayothin, 2002)
Then, A = Initial concentration (mg/L), B =
Final concentration (mg/L)
The results were investigated by using the
least significant difference at a 95% confidence
level by SPSS.
Results and Discussion
Characteristics of wastewater
The wastewater sample was collected from
battery manufacturing Bang Na, Bangkok. The
characteristics of wastewater were presented in
Table 1. The pH of wastewater was strongly acid
and initial lead concentration was higher than
wastewater quality standard control of Thailand
Industrial Work Department in 1992.
Chemical and physical properties of egg shells
The chemical composition of all egg shells
were examined by x-ray fluorescence spectrometer
(XRF; S4-Explorer) and the results were shown in
Table 2. It was demonstrated that all egg shells
had similar chemical contents which mainly
composed of CaCO3 and a few of other elements;
i.e. S, Mg, P, Al, K and Sr.
The surface structure of 4 types of egg shells
were observed by scanning electron microscope
(SEM) as shown in Figure 1. It showed that egg
shell surfaces were irregular shape. Pore sizes of
Table 1. Characteristics of wastewater from
battery manufacturing
Parameter Value of each Industrial effluent
parameter* standard**
Lead (mg/L) 2.365 < 0.2
Cadmium (mg/L) N.D. < 0.03
Copper (mg/L) N.D. < 1.0
SS (mg/L) 18.13 < 30
TS (mg/L) 2,245.60 -
TDS (mg/L) 2,227.47 < 2000 or < 5000
pH 1.35-1.45 5.0-9.0
* The Battery Manufacturing from Bangna, Bangkok
** Wastewater quality standard control of Thailand
Industrial Work Department, 1992
Figure 1. Morphology of 4 types of egg shell
with magnification of x 5,000
(a) Natural hen egg shell
(b) Boiled hen egg shell
(c) Natural duck egg shell
(d) Boiled duck egg shell
(b)
(d)
Songklanakarin J. Sci. Technol.
Vol. 29 No. 3 May - Jun. 2007 Removal of lead from battery manufacturing wastewater
Arunlertaree, C., et al.
861
Table 2. Chemical compositions of egg shells
Weight (%)
Element Natural hen Boiled hen Natural duck Boiled duck
egg shell egg shell egg shell egg shell
CaCO3 96.48 96.48 96.48 95.99
S 2.31 3.59 1.24 1.92
Mg 0.404 0.440 0.996 0.927
P 0.501 0.469 0.508 0.481
Al - - - 0.309
K - - 0.0839 0.00957
Sr 0.0737 0.0734 0.118 0.093
of solution. Chemical precipitation was the main
process in adjusted pH wastewater (pH 5, 6 and
7), when pH level reached the optimum point,
lead will precipitate as confirmed in Figure 2.
Solubility of lead continuously decreased from
pH 4 until it was in stable form at pH 7.
2. Effect of contact time (Unadjusted pH
wastewater, 0.05 g egg shell /100 ml of waste-
water) The results were shown in Table 4 and
Figure 4. Removal efficiency for all types of egg
shell at the contact time of 90, 120 and 150 mins
was not significantly different, whereas the results
obtained at contact time 30, 60 and 90 mins were
natural and boiled hen egg shells were between
0.3-0.6 µm while those of natural and boiled duck
egg shells were between 0.2-0.4 µm.
Numerous studies have reported that the
pore structure particulary affects by adsorption
capacity (Surasen, 2002; Polamesanaporn, 2001);
pictures from scanning electron microscope (SEM;
HITACHI S-2500) showed that natural and boiled
duck egg shells had more pores per square-centi-
meter than natural and boiled hen egg shells. This
result was inconsistent with Kasetsuwan (1979).
Moreover, amount and distribution of protein fiber
in natural hen and duck egg shells were higher
than in boiled hen and duck egg shells, as shown
in Figure 1.
Optimum conditions for lead removal by egg
shells 1. Effect of pH (0.05 g egg shell/100 ml
of wastewater, 90 mins of contact time)
The results were shown in Table 3 and
Figure 3. Lead removal efficiency changed signi-
ficantly at different pH. Optimum removal
efficiency of all types of egg shells was at pH 6
but unadjusted pH wastewater was conducted in
the next step of the experiment because the final
concentration of lead at pH 6 was too low for study
of adsorption isotherm. Unadjusted pH waste-
water decreased the use of expensive chemical
reagent for adjusting pH and reduced chemical
residues in the environment due to basic properties
of egg shell which immediately increased the pH Figure 2. Mineral solubility in Pb-O-H-S-C system
at 25oC, 1 atm (Rose et al., 1979)
Songklanakarin J. Sci. Technol.
Vol. 29 No. 3 May - Jun. 2007 862
Removal of lead from battery manufacturing wastewater
Arunlertaree, C., et al.
Table 3. Effect of pH on lead removal
Natural Hen Boiled hen Natural duck Boiled duck
egg shell egg shell egg shell egg shell
Final Removal Final Removal Final Removal Final Removal
conc. Efficiency conc. Efficiency conc. Efficiency conc. Efficiency
(mg/L) (%) (mg/L) (%) (mg/L) (%) (mg/L) (%)
5 1.063 0.587±0.015 a 44.78 0.650±0.014 a 38.82 0.546±0.013 a 48.67 0.630±0.014 a 40.70
6 0.349 0.077±0.005 b 78.03 0.094±0.006 b 72.97 0.073±0.004 b 79.18 0.086±0.005 b 75.36
7 N.D. N.D. c 100 N.D. c 100 N.D. c 100 N.D. c 100
Remark: Differences of superscripts in each column indicate statistically significant differences with the confidence of
95% by LSD
pH Initial
conc.
(mg/L)
Table 4. Effect of contact time on lead removal
Natural Hen Boiled hen Natural duck Boiled duck
egg shell egg shell egg shell egg shell
Final Removal Final Removal Final Removal Final Removal
conc. Efficiency conc. Efficiency conc. Efficiency conc. Efficiency
(mg/L) (%) (mg/L) (%) (mg/L) (%) (mg/L) (%)
30 2.365 2.017±0.005 a 14.70 2.179±0.007 a 7.86 1.456±0.009 a 17.28 2.117±0.008 a 10.48
60 2.365 1.831±0.015 b 22.58 2.003±0.014 b 15.29 1.661±0.014 b 29.76 1.936±0.011 b 18.15
90 2.365 1.637±0.006 c 30.79 1.819±0.008 c 23.10 1.544±0.006 c 34.73 1.747±0.004 c 26.13
120 2.365 1.634±0.012 c 30.92 1.821±0.016 c 22.99 1.536±0.007 c 35.07 1.734±0.015 c 26.70
150 2.365 1.631±0.011 c 31.03 1.821±0.013 c 22.99 1.535±0.013 c 35.09 1.733±0.013 c 26.74
Remark: Differences of superscripts in each column indicate statistically significant differences with the confidence of
95% by LSD
Initial
conc.
(mg/L)
Contact
time
(mins)
Table 5. Effect of dose of egg shell on lead removal
Natural Hen Boiled hen Natural duck Boiled duck
egg shell egg shell egg shell egg shell
Final Removal Final Removal Final Removal Final Removal
conc. Efficiency conc. Efficiency conc. Efficiency conc. Efficiency
(mg/L) (%) (mg/L) (%) (mg/L) (%) (mg/L) (%)
0.05 2.365 1.637±0.006a30.80 1.819±0.009a23.04 1.544±0.004a34.74 1.747±0.005a26.15
0.20 2.365 0.698±0.009b70.50 0.950±0.008b59.83 0.513±0.006b78.31 0.884±0.005b62.62
0.50 2.365 0.359±0.011c84.83 0.548±0.018c76.83 0.271±0.006c88.53 0.441±0.012c81.37
1.00 2.365 0.082±0.004d96.53 0.122±0.005d94.84 0.059±0.005d97.51 0.099±0.008d95.81
1.50 2.365 0.088±0.009d96.42 0.120±0.006d94.94 0.051±0.003d97.56 0.097±0.013d95.76
Remark: Differences of superscripts in each column indicate statistically significant differences with the confidence of
95% by LSD
Initial
conc.
(mg/L)
Dose of
egg
shell
(g)
significantly different. Therefore, the optimum
contact time for all types of egg shell should be at
90 mins. This result was consistent with Pawebang
and Sukcharoen (1999), who reported that the
equilibrium time to remove lead in synthetic waste-
water by egg shell could be reached at about 80
min. Similary the study of Lee et al. (1998) on the
removal of lead by crab shell particle showed that
Songklanakarin J. Sci. Technol.
Vol. 29 No. 3 May - Jun. 2007 Removal of lead from battery manufacturing wastewater
Arunlertaree, C., et al.
863
the necessary contact time to reach equilibrium
was about 90-120 mins.
3. Effect of dose of egg shell (Unadjusted
pH wastewater, 90 mins of contact time)
The results were shown in Table 5 and
Figure 5. Removal efficiency for the doses of all
types of egg shell of 0.05, 0.2, 0.5, and 1.0 g were
significantly different whereas the results obtained
from using 1.0 and 1.5 g. were not significantly
different. Therefore, an appropriate dose for all
types of egg shell should be 1.0 g. Dose of egg
shell affected the removal of lead, because the
removal efficiency of solutes increased with
increasing dose of adsorbent (Eamsiri et al., 2005).
The removal efficiency increased according to the
increasing dose of egg shell at an appropriate
level. According to the chemical composition
analysis in Table 2, egg shell mainly composed of
CaCO3. Major alkaline contributors in egg shell
was CaCO3 so it was expected that any aqueous
solution equilibrated with egg shell became more
basic that confirmed by following mechanism
(Brown and Lemay, 1985).
CaCO3Ca2+ + CO3
2-
CO3
2- + H2O HCO3
- + OH-
Hydrolysis reaction of CaCO3 gave basic
solution because Ca2+ and OH- increased the pH of
the solution as well as in this experiment, adding
various doses of egg shell into wastewater
increased the pH of solution as shown in Table 6.
This basic property of egg shells, which
increased the pH of solution, was of advantage to
decrease the use of expensive chemical reagent for
adjusting pH of wastewater (decreasing operation
cost) and reduced chemical residues in the envi-
ronment. At optimum condition (1.0 g of egg shell/
100 ml of wastewater), the final pH and final
concentration of lead were lower than wastewater
quality standard control of Thailand Industrial
Work Department, 1992
Adsorption isotherm
Experiments were conducted to determine
the adsorption isotherm of lead using egg shells
at 0.05, 0.2, 0.5, 1.0 and 1.5 g in 100 ml of un-
adjusted pH wastewater (pH 1.35-1.45). Initial
lead concentration was approximately 2.365 mg/
L. The experimental datas were calculated to
determine the adsorption isotherm by using the
Langmuir and Freundlich models.
The Langmuir equation was expressed as :
Figure 3. Effect of pH on lead removal by 4 types
of egg shell
Figure 4. Effect of contact time on lead removal
by 4 types of egg shell
Figure 5. Effect of dose of egg shell on lead
removal by 4 types of egg shell
Songklanakarin J. Sci. Technol.
Vol. 29 No. 3 May - Jun. 2007 864
Removal of lead from battery manufacturing wastewater
Arunlertaree, C., et al.
Q
e
=X
m
bC
e
1+bC
e
(Samuel and Osman,1987)
where;X = the amount of solute adsorbed per unit
weight
Xm= amount of solute adsorbed per unit
weight of adsorbent required for
monolayer coverage of the surface
B = a constant related to the heat of
adsorption
Ce= equilibrium concentration of the
solute
For linearization of the data, Equation could be
written in the form :
C
e
Q
e
=1
bX
m
+C
e
X
m
Plotting Ce/Qe against Ce, a straight line, slope was
1/Xm and an intercept is 1/bXm. The b value was
the ratio between adsorption rate and desorption
rate. Xm could be used to compare the removal
efficiency of each adsorbent.
The Freundlich equation was expressed as :
x
m=KC
e1/n
(Samuel and Osman,1987)
where;x = the amount of solute adsorbed
m = the weight of adsorbent
Ce= the solute equilibrium concentration
K and 1/n = constants characteristic of the
system
For linearization of the data, the Freundlich equa-
tion was written in logarithmic form :
Log Q
e
=logK+1
nlogC
e
; (Q
e
=x
m)
Plotting Log Qe against log Ce, a straight line, slope
was 1/n and intercept was log K. The calculated n
value was qualitative related to the distribution of
site bonding energies. K values could be used to
compare the removal efficiency of each adsorbent.
The final concentrations (Ce) of lead, as
shown in Table 7, were plotted as Ce/Qe versus Ce
for the Langmuir model as shown in Figure 6, and
log Qe versus log Ce for the Freundlich model
(Figure 7), and values of the constants for each
type of egg shells were determined after lineariz-
ing the equations through linear regression analy-
sis. The K values and all constant values in
Langmuir (Xm,b) and Freundlich (K,1/n) equations
were also presented in Table 8. In our experimental
ranges, the results of all egg shells tended to be
described by the Freundlich model, because the
regression line obtained from the Freundlich curve
fit better than the Langmuir curve. K values in
Freundlich equation could be used to compare the
removal efficiency of each adsorbent. It was
shown that the descending lead removal efficiency
on K value of each egg shell was natural duck egg
shell (K = 1.2362), natural hen egg shell (K =
0.9889), boiled duck egg shell (K = 0.7901) and
boiled hen egg shell (K = 0.6834), respectively.
The n values obtained from this study were higher
than 1, which may indicate that the energies of
adsorption were decreased with increasing surface
area of egg shell that bind with the heavy metal
ion. The results were consistent with Polamesana-
Table 6. Final pH at various doses of egg shell
Final pH at various doses of egg shell
Natural hen Boiled hen Natural duck Boiled duck
egg shell egg shell egg shell egg shell
0.05 1.45±0.01 1.43±0.02 1.45±0.02 1.44±0.04
0.20 1.75±0.02 1.74±0.01 1.76±0.02 1.73±0.02
0.50 4.48±0.03 4.44±0.03 4.52±0.01 4.44±0.02
1.00 5.85±0.01 5.80±0.02 5.89±0.03 5.82±0.02
1.50 5.88±0.02 5.85±0.02 5.92±0.02 5.84±0.01
Dose of
Egg shell
(g)
Songklanakarin J. Sci. Technol.
Vol. 29 No. 3 May - Jun. 2007 Removal of lead from battery manufacturing wastewater
Arunlertaree, C., et al.
865
porn (2001), who found that the Cd removal
efficiency of natural hen egg shell was higher
than protein - removed hen egg shell.
From this experiment, natural hen and duck
egg shells have more protein fiber than boiled hen
and duck egg shells when observed by SEM. Thus
protein fiber which comprising of carboxyl and
amine groups may promote the natural duck and
Table 7. Final concentration of lead at various doses of egg shell and adsorption
capacity
Types of Dose of Final Solute Adsorption
egg shell egg shell Conc. Adsorbed capacity Ce/QeLog CeLog Qe
(g) (mg/L) (mg) (mg/g)
mC
exQ
e, x/m
Natural hen 0.05 1.637 0.073 1.457 1.124 0.214 0.163
egg shell 0.20 0.698 0.167 0.834 0.837 -0.156 -0.079
0.50 0.359 0.201 0.401 0.895 -0.445 -0.397
1.00 0.082 0.228 0.228 0.359 -1.086 -0.641
1.50 0.088 0.228 0.152 0.580 -1.056 -0.819
Boiled hen 0.05 1.819 0.055 1.092 1.665 0.260 0.038
egg shell 0.20 0.950 0.950 0.708 1.343 -0.022 -0.150
0.50 0.548 0.201 0.363 1.508 -0.261 -0.440
1.00 0.122 0.224 0.224 0.544 -0.914 -0.649
1.50 0.120 0.225 0.150 0.802 -0.921 -0.825
Natural duck 0.05 1.544 0.082 1.643 0.940 0.189 0.216
egg shell 0.20 0.513 0.185 0.926 0.554 -0.290 -0.033
0.50 0.271 0.201 0.419 0.647 -0.567 -0.378
1.00 0.059 0.231 0.231 0.256 -1.229 -0.637
1.50 0.051 0.231 0.154 0.331 -1.292 -0.812
Boiled duck 0.05 1.747 0.062 1.236 1.414 0.242 0.092
egg shell 0.20 0.884 0.148 0.741 1.194 -0.054 -0.130
0.50 0.441 0.192 0.385 1.146 -0.356 -0.415
1.00 0.099 0.227 0.227 0.437 -1.004 -0.645
1.50 0.097 0.227 0.151 0.642 -1.013 -0.820
Table 8. Constants and correlation coefficients for lead removal with
4 types of egg shell
Langmuir model Freundlich model
XmbR
2K 1/n R2
Naturalhen 2.5602 0.7297 0.7283 0.9889 0.6923 0.9553
egg shell
Boiled hen 1.7908 0.7207 0.6829 0.6834 0.6453 0.9423
egg shell
Natural duck 2.5094 1.1347 0.8250 1.2362 0.6600 0.9680
egg shell
Boiled duck 1.9547 0.8095 0.7467 0.7901 0.6441 0.9570
egg shell
Type of
egg shell
Songklanakarin J. Sci. Technol.
Vol. 29 No. 3 May - Jun. 2007 866
Removal of lead from battery manufacturing wastewater
Arunlertaree, C., et al.
Figure 6. Langmuir adsorption isotherm on lead removal by 4 types of egg shells
Figure 7. Freundlich adsorption isotherm on lead removal by 4 types of egg shell
hen egg shell to bind lead ions better than boiled
duck and hen egg shell. Moreover, acid condition
of wastewater may cause protein fiber in natural
hen and duck egg shell to be contracted and
tightly captured, blocking the reaction between H+
and CaCO3. This phenomenon resulted in de-
creasing solubility of natural hen and duck egg
shell so that the amount of adsorbent increased.
In addition, removal efficiency of duck egg shell
was higher than that of hen egg shell because duck
egg shells had more pores per square-centimeter
than hen egg shells, that was consistent with
Kasetsuwan (1979). Chemical composition analy-
sis from XRF in Table 2 indicated that CaCO3 in
Songklanakarin J. Sci. Technol.
Vol. 29 No. 3 May - Jun. 2007 Removal of lead from battery manufacturing wastewater
Arunlertaree, C., et al.
867
4 types of egg shells may slightly affect the
removal efficiency.
From this study, removal of lead might
occur through more than one type of mechanism
i.e., adsorption and precipitation, especially at the
high doses of egg shell (0.5-1.5 g/100 ml of
wastewater) which increased final pH more than
4 so precipitation might take part in the adsorp-
tion process. As confirmed with Figure 2, the
solubility of lead continuously decreased from pH
4 until it was in stable form at pH 7; as a result
lead might form complexes with OH- as Pb(OH)2,
so lead hydroxyl species might participate in the
adsorption and precipitate onto the egg shell
structure. However, at low dose of egg shell (0.05-
0.2 g/100 ml of wastwater), the final pH of solu-
tion was lower than 4 so adsorption was the main
mechanism.
These results were consistent with other
studies performed with basic adsorbent material
i.e., fly ash and bentonite. The mechanism that
influenced zinc removal characteristics of bentonite
was adsorption, ion exchange and precipitation (at
the high pH level i.e., pH 8), zinc might form
complex with OH- so zinc hydroxyl species might
participate in the adsorption and precipitate onto
the bentonite structure (Kaya and Oren, 2005).
Moreover, the results were consistent with Boon-
paniad (1998) who studied the removal of lead and
zinc by fly ash. Hydroxide ion might participate
in the adsorption process and increase the pH
of solution so adsorption capacity was increased.
Formation of Pb(OH)2 on the surface of ash was
presumably the mechanism followed by adsorp-
tion. Precipitation of some Pb(OH)2 could be
deposited on fly ash particles.
Conclusion
The results from this work showed that the
optimum pH was at pH 6 but final concentration
of lead was too low for study of adsorption iso-
therm, so unadjusted pH wastewater was used in
this study. Unadjusted pH wastewater decreased
the use of expensive chemical reagent for adjust-
ing pH and reduced chemical residues in the
environment due to basic properties of egg shell
which immediately increased pH of solution. The
optimum contact time and optimum dose of egg
shell were 90 mins and 1.0 g/100 ml of waste-
water, respectively. Final concentration of lead at
optimum condition was lower than the wastewater
quality standard.
The adsorption isotherm data tended to fit
with the Freundlich model. From this research,
precipitation might take part in the adsorption
process, especially at the high doses of egg shell.
The result of the adsorption isotherm demonstrated
that the descending lead removal efficiency was
natural duck egg shell, natural hen egg shell, boiled
duck egg shell and boiled hen egg shell, respect-
ively. (as discussed earlier). In the study of adsorp-
tion isotherm, final pH should be stable but in this
experiment, final pH varied according to various
doses of egg shell. This was the limitation of using
real wastewater for uncontrolled final pH and it
was different from synthetic wastewater. When
fixed dose of egg shell was added into various
initial concentration of synthetic wastewater, final
pH was stable.
In summary, the egg shell could remove
lead due to its physical and chemical properties
such as CaCO3 contents (95-96 %), pore structure
and functional group i.e., carboxyl, amine and
sulfate group. Moreover, egg shell was a neutraliz-
ing agent, any aqueous solution equilibrated with
egg shell became more basic so heavy metals
could precipitate and deposit on egg shell particles.
Acknowledgements
The authors would like to thank Faculty
of Graduate Studies, Mahidol University for
Supported in Part by the Thesis Grant. Apprecia-
tion was also expressed to Mr. Somnuk Parnthong
at Battery Organization, Bang Na, Bangkok, for
supporting with wastewater used in this study
and all staffs at the Central Instrument Facility
(CIF), Center of Nanoimaging and Department of
Chemistry at Faculty of Science, Mahidol Uni-
versity for supporting with AAS, SEM and XRF.
Songklanakarin J. Sci. Technol.
Vol. 29 No. 3 May - Jun. 2007 868
Removal of lead from battery manufacturing wastewater
Arunlertaree, C., et al.
References
American Public Health Association, American Water
Works Association and Water Pollution Control
Federation (APHA, AWWA and WPCF).1995.
Standard method for the examination of water
and wastewater. Nineteen Edition, American
Public Health Association, Washington D.C.
Boonpanaid, C. 1998. Removal of metal ions from
aqueous solution by activated carbons and coal
fly ash. [M.Sc.Thesis in Applied Analytical and
Inorganic Chemistry]. Bangkok: Faculty of
Graduate Studies, Mahidol University.
Brown, T.L. and Lemay, H.E.Jr. 1985. Chemistry The
Central Science Health, Prentice-Hall Publishing,
New Jersey.
Eamsiri, A., Arunlertaree, C. and Datchaneekul, K.
2005. Removal of heavy metals in synthetic
wastewater by adsorption on bentonite, Envi.
and Natural Res., 3: 21-30.
Eckenfelder, W. 1980. Principles of Water Quality
Management. CBI Publishing Company, Inc.,
Boston.
Kasetsuwan, S. 1979. Egg and chicken, Kasetsart Uni-
versity, Bangkok. (in Thai)
Kaya, A. and Oren, A.H. 2005. Adsorption of zinc from
aqueous solutions to bentonite, Hazard. Mat.,
125: 183-189.
Kosayothin, K. 2002. Removal of Heavy Metal in
Wastewater from Water Quality Analysis Lab-
oratory by Bagasse. [M.Sc.Thesis in Technology
of Environmental Management]. Bangkok: Fac-
ulty of Graduate Studies, Mahidol University.
Lee Moo-Yeal, Lee Sung-Ho, Shin Hyun-Jae, Kajiuchi
Toshio and Yang Ji-Won. 1998. Characteristics
of lead removal by crab shell particles, Process
Biochem., 33: 749-753.
Pawebang, P. and Sukcharoen. 1999. Comparative
studies on adsorption of lead by egg shell and
fish scale, Sci. and Tech., 2: 51-57. (in Thai)
Phomun, N. 2002. Lead Removal from Battery Manu-
facturing Wastewater by Rice Husk Ash. [M.
Eng. Thesis in Environmental Engineering].
Bangkok: Faculty of Graduate Studies, Kaset-
sart University. (in Thai)
Polamesanaporn, Y. 2001. Development of an adsorb-
ing material from egg shell for the removal of
cadmium. [M.Sc. Thesis in Natural Resource
Management]. Bangkok: Faculty of Graduate
Studies, King Mongkut University of Techno-
logy Thonburi. (in Thai)
Pollution Control Department. 1997. Manual of
Industrial Wastewater Collecting, Ruenkaew
Publishing, Bangkok.
Rose, A.W., Hawkes, H.E.and Webb, J.S. 1979. Geo-
chemistry in Mineral Exploration 2ed, Academic
press Inc, London.
Samuel, D.F. and Osman, M.A. 1987. Adsorption
Process for Water Treatment, Butterworth
Publishing, London.
Surasen, C. 2002. Removal of Cadmium in Synthetic
Wastewater by Egg Shell Filter [M.Eng. Thesis
in Environmental Engineering]. Bangkok: Fac-
ulty of Graduate Studies, Kasetsart University.
(in Thai)
