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Arab Journal Of Nuclear Science And Applications, 46(2),(1-16) 2013
iii. Effect of particle size
The effect of particle size using the size ranging 5 – 15 µm of Poly-acrylic acid/2-hydroxy
ethylemethacrylate (P-AAc/HEMA) on the removal of Eu3+ , Nd3+ , Sr2+ , Co2+ , Cd2+ and Zn2+ ions was
studied at room temperature. Figures. (10-1) : (10-6) show the effect of contact time at different
particle sizes. The capacity of aforementioned ions sorption at the equilibrium was calculated and
found to increase with the decrease of the adsorbent particle sizes indicating that the ions sorption
occurs by a surface mechanism, as shown in Table (2). It was also observed that the variation in
particle size affects on the equilibrium time. Thus, for particle size 5 µm, the time required to reach
equilibrium is about 50 minutes for metal ions. While for particle sizes 15 µm, the time necessary is
about 80 minutes for the metal ions. Consequently, increasing particle size increases the time needed
to reach equilibrium. These results suggest that the sorption kinetic of Eu3+ , Nd3+ , Sr2+ , Co2+ , Cd2+ and
Zn2+ ,ions by Poly-acrylic acid/2-hydroxyethylemethacrylate (P-AAc/HEMA) is largely determined by
the particle size.
Table (2) Effect of particle size of P-AAc/AN on the capacity of
Zn2+ , Cd2+ Co2+ , Sr2+ , Nd3+ and Eu3+ Fig.(9): Effect of contact time on the % uptake in case
of P-AAc/HEMA.
ions.
Metal ion Zn Cd Co
Particle size,
µm
Capacity,
meq/g
5 10 15 5 10 15 5 10 15
3.84 2.56 1.87 3.55 2.91 1.74 3.62 2.68 1.81
Metal ion Sr Nd Eu
Particle size,
µm
Capacity,
meq/g
% uptake
100
80
60
40
20
0
0 20 40 60 80 100 120
5 10 15 5 10 15 5 10 15
4.3 3.1 2.22 4 2.95 2.32 4.6 3.66 2.72
8
time, mint.
Sr
Nd
Eu
Co
Cd
Zn