1-s2.0-S2212667813001007-main
Click here to load reader
-
Upload
serazawa-gps -
Category
Documents
-
view
212 -
download
0
Transcript of 1-s2.0-S2212667813001007-main
IERI Procedia 5 ( 2013 ) 232 – 237
2212-6678 © 2013 The Authors. Published by Elsevier B.V.Selection and peer review under responsibility of Information Engineering Research Institutedoi: 10.1016/j.ieri.2013.11.097
L
N
c P
Abst
In thpistaobtaiparamhas t(R2= © 20Sele Keyw
* E-
2013 Inter
LinearizeAd
Nahid Ghas
a
Process Systems E
tract
he present studyacia atlantica shined from this meters obtainedthe maximum
=0.996).
013. Publishedection and pee
words: Pseudo-sec
Corresponding a-mail address
rnational Co
ed Equadsorption
semia*, Par
aDepartment of C
Engineering Centr
y, four forms ohells were inves
study show thd is recommend
amount of ad
d by Elsevier r review unde
cond-order, Kinet
author. Tel.: +98 8s: n-ghasemi@iau
onference o
ations of n of Pb(
rya Tamria,R
Chemistry, SciencsbThe A
re (PROSPECT),
f pseudo seconstigated. Kinetichat not only thded to calculatedsorbed of Pb(
B.V. er responsibilit
tics, Pb(II), Adso
8613670017; faxu-arak.ac.ir
n Agricultu
f Pseudo (II) on Pi
, Ali KhadRafidah Wa
se Faculty,Islamieine Nasim Comp Faculty of ChemSkudai, Johor, M
nd (PS) order kic parameters de
he parameters oe the PS-order p(II) at equilibr
ty of Informat
orption
: +988613670017
ural and Nat
Second-istacia A
emia, Nasean Alwic
ic Azad Universitpany- Arak, Iran
mical EngineeringMalaysia
inetic linearizeetermined for aobtained can beparameters by trium(qe=50.000
tion Engineer
7.
tural Resour
-order KAtlantica
er Sareban
ty, Arak Branch, A
g, Universiti Tekn
d equations forall forms of linee differed but the linearized e mgg-1) and c
ing Research
rces Engine
Kinetic foa Shells
nezhadb, S
Arak, Iran
nologi Malaysia ,
r the adsorptionearized equationalso based onquation 1, beca
coefficient of d
Institute
eering
or the
Sharifah
81310 UTM
n of Pb(II) by ns and results n the kinetic ause this form determination
Available online at www.sciencedirect.com
© 2013 The Authors. Published by Elsevier B.V.Selection and peer review under responsibility of Information Engineering Research Institute
ScienceDirect
233 Nahid Ghasemi et al. / IERI Procedia 5 ( 2013 ) 232 – 237
Introduction
Removal of heavy metals in treatment of wastewater has long been considered. The research of adsorption is important because it provides noteworthy viewpoint into the reaction trajectory and the mechanism of sorption reactions, also demonstrates the solute adsorbed rate[1]. According to Ho studies on sorption is provided PS-order rate expression[2]. Also, Azizian reported the analysis of a theoretical model of PS-order [3]. For low initial concentration from a solute, the Azizian’s extraction has advantage because the sorption process will follow the PS-order model. The first advantage of PS-order equation is that it doesn’t have any problem to assign a capacity of effective sorption. Also the rate of initial sorption, the capacity of sorption and the PS-order constant rate can be determined from the equation with unknown parameter. The final advantage is that by using batch reactions at various concentrations of initial sorption, different particle sizes, speeds of agitation, doses of sorbent, values of pH and different temperatures, the type of sorbent and sorbate, the kinetic studies can be carried out.
In this research, the pistacia atlantica shells was applied for the adsorption of Pb (II) ions from wastewater as adsorbent. The research focuses on adsorption kinetics studies of the prepared adsorbent and four PS-order kinetic linear equations have been applied to test.
1. Experimental
1.1. Materials and methods
The experiments were conducted using pistacia atlantica shells obtained from Eilam-Iran. At first it was washed five times with hot deionized water to take the impurities, and was then dried at 105 oC for 24 h in an oven, and was after screened with a sieve (120 mesh). The sieved pistacia atlantica shells was soaked with H2SO4 at 1:1 ratio for overnight. The acidic solution was then removed, and the pistacia atlantica shells was rinsed until the pH=7 with distilled water to remove excess H2SO4. The powder obtained from the pistacia atlantica shells become dry for 2 h at 105°C. The main solution of Lead nitrate (1000 mg L-1) was ready with purified water using Lead nitrate salt. Different concentrations of solutions of Pb (II) are ready from the main solution when necessary.
The pistacia atlantica shells (0.1 gr) was added to a 120 mL Erlenmeyer containing 70 ml of 100 mg L-1 of Pb(II) with pH =4, stirred at 150 rpm and at temperature 298 K. Samples were taken at proper time intervals (5-120 minutes) and the filtrate analysed by Atomic Absorption Spectrophotometer (AAS). By using HNO3 or NaOH (0.1N), initial pH was adjusted.
PS- order
The PS-order kinetic rate equation [4] which is generally extracted in Equation (1):
(1)
Where k(gmg-1min-1) is PS-order rate constant of adsorption, qe and qt (mgg 1) are named the adsorption capacity at time of equilibrium and t. Integrating Equation (1) with applying border conditions t=0 and t=t , qt=0and qt=qt , gives:
(2)
234 Nahid Ghasemi et al. / IERI Procedia 5 ( 2013 ) 232 – 237
In general, due to its simplicity, the PS-order kinetic has been widely applied in the designing of very adsorption methods[5]. Sinc the PS-order which explained by Equation (2) is non linear, seem that appraising the value of qe and the rate constant of adsorption k needs adjusting the equation to empirically results by non linear of regression applying methods of numeric optimization. A proper choice for non-linear of regression is to apply linearized variants of the equations that the PS-order kinetic could be linearized to four versions (Table 1) for the calculation of parameters of qe and k [6].
Table 1. PS-order kinetic linearized forms [6]
(Fig. 1) and (Fig. 2), linearized versions 1 and 2 of the PS-order kinetic equations have t/q and 1/q on their
Y axis, that amounts of numeric low of Y whereas q is great. As observed in linearized versions equations 2 and 3 (Fig. 3), in t and q, the errors of the experimental distribution, if the axises be the versus 1/t or 1/q will change. There is also a difficulty in incorrect relation in linearized versions 1, 3 and 4(Fig. 4). It often takes place that the proportional relation of variables was applied to make of a variable relationship among the variables their selves [6]. An empirical error was presented in the X axis variable, as in linearized versions 3 and 4 observed, if the axis of X is (q/t or q), many experimental methods have unimportant errors in measuring t.
Fig. 1. linearized versions-1 equation of PS-order obtained during the adsorption of Pb(II) by using pistacia atlantica shells
linearized versions equation
1 =
2
3
4
235 Nahid Ghasemi et al. / IERI Procedia 5 ( 2013 ) 232 – 237
Fig. 2. linearized versions-2 equation of PS-order obtained during the adsorption of Pb(II) by using pistacia atlantica shells
Fig. 3. linearized versions-3 equation of PS-order obtained during the adsorption of Pb(II) by using pistacia atlantica shells
All of parameters for four linearized versions of PS-order kinetic equations included qe and k and the coefficient of determination, R2 listed in Table 2. These parameters were determined from the slope time and the intercept of a straight line according to equations that given in Table 1.
y = 2.283x + 44.91R² = 0.646
0
10
20
30
40
50
60
0 2 4 6 8
q
q/t
y = 0.049x + 0.022R² = 0.723
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035
0 0.05 0.1 0.15 0.2 0.25
1/q
1/t
236 Nahid Ghasemi et al. / IERI Procedia 5 ( 2013 ) 232 – 237
Fig. 4
Table
2. C
Tversof Pprovkinemggexpe
Ack
T
4. linearized versi
e 2. Parameters of
Conclusions
The experimenions equation
PS-order by uvided accurateetic linearizedg-1,respectivelyerimental data
knowledgemen
The authors are
ions-4 equation o
f PS-order kinetic
linearized
4
ntal outcome wns. Based on thusing the linee evaluates ind versions equy(Table 2). Tha (qe.Exp=48.57
nts
e special thank
of PS-order obtain
c determined by u
d versions
1
2
3
were analysedhe outcome oearized version very cases. Auations, the she results also75 mgg-1) (Fig
kful to Mr Na
ned during the ad
using the lineariz
qe(mgg-1)
50.000
45.454
44.914
47.243
d and determinf this research
ons of 2, 3 aAccording to sorption capaco showed a goog. 5).
aser Sareban n
dsorption of Pb(II)
ed versions equat
Param
k(g mg-1 m
0.0033
0.0098
0.0097
0.0059
ned accordingh, it is not recand 4. The P
the evaluatiocity were obtod fit between
nezhad for the
) by using pistaci
tions
meters
min-1) R
3 0
8 0
7 0
0.64
g to the four Pcommended toS-order linea
on using the atained 49.751n linearized ve
financial supp
ia atlantica shells
R2
0.996
0.723
0.646
47
PS-order kinetio calculate therized version
all PS-order li, 45.454, 44.ersion equatio
port of this stu
ic linearized e parameters
n equation 1 inear kinetic 914, 47.138
on 1 with the
udy.
237 Nahid Ghasemi et al. / IERI Procedia 5 ( 2013 ) 232 – 237
References
[1] Ho Y S, Mckay G. Pseudo-second order model for sorption processes. Process Biochemistry 1998; 34: 451-465. [2] Ho Y S. Pseudo-Isotherms Using a Second Order Kinetic Expression Constant. Adsorption 2004; 10: 151–158. [3] Ho Y S. Second-order kinetic model for the sorption of cadmium onto tree fern: a comparison of linear and non-linear methods Water Res 2006; 40: 119–125. [4] Bhattacharyya, K.G, Sharma A. Adsorption of Pb(II) from aqueous solution by Azadirachta indica (Neem) leaf powder. J. Hazard. Mater 2004; B113: 97–109. [5] Ho Y S. Review of second-order models for adsorption systems. J. Hazard. Mater 2006;136: 681–689. [6] M.I. El.Khaiary, G.F. Malash, Y.S.Ho ,On the use of linearized pseudo-second-order kinetic equations for modeling adsorption systems. Desalination 2010; 257: 93–101.