4 Effect of Incorporated Inorganic Nanoparticles on Porous Structure. . .
73
Vs/Vi
0
5000
10000
0
1
x
G
B
C
3
m
d
l
o
m
m
/
-3
0
5
10
15
Dowex MAC-3
Dowex MAC-3/ZHP
Dowex HCR-S
Dowex HCR-S/ZHP
b
a
-3
Fig. 4.8 Ni 2+ (a) and BG (b) concentration in the solution at the column outlet vs ratio of volumes
of the solution (V s ) and ion-exchanger
reaction (see Table 4.3 and Fig. 4.5). Thus, higher breakthrough capacity of the
nanocomposite is due to its improved selectivity toward transition metal ions [23].
This material better removes Ni 2+ ions from water containing also hardness ions.
Regarding the modified weakly acidic resin, its advantage over the pristine resin is
caused by faster sorption and evidently by better selectivity.
Modification decreases breakthrough capacity of the strongly acidic resin toward
BG (due to slower adsorption on the nanocomposite comparing with the pristine
resin) and increases this value for the weakly acidic ion exchanger (this is evidently
caused by higher adsorption capacity and faster adsorption on the nanocomposite).
In order to remove both organic dyes and inorganic anions from mixed solutions
under dynamic conditions, a mixture of the nanocomposites based on strongly and
weakly acidic resins is recommended.
4.7 Conclusions
The modified cation-exchanger contain ZHP particles with size from several
nanometers to several microns. Single nanoparticles are located in pores containing
functional groups; aggregates occupy inert pores. From the formal point of view,
non-aggregated nanoparticles can be considered as a cross-linking agent, which
increases swelling pressure. Swelling pressure provides stretching of transport
pores. As a result, porous structure of the polymer constituent is transformed:
some regions of the polymers, which are able to interact with species, become
unavailable for them. However, embedded ZHP particles evidently expand the range
of pores, where adsorption is possible. This is valid both for BG adsorptions on
weakly and strongly acidic resins. It is the same for Ni 2+ ion sorption on strongly
acidic resins. The particles decrease sorption rate by this manner. At the same time,
strong interaction with Ni 2+ ions is attributed to the weakly acidic resin. Indeed,
73
Vs/Vi
0
5000
10000
0
1
x
G
B
C
3
m
d
l
o
m
m
/
-3
0
5
10
15
Dowex MAC-3
Dowex MAC-3/ZHP
Dowex HCR-S
Dowex HCR-S/ZHP
b
a
-3
Fig. 4.8 Ni 2+ (a) and BG (b) concentration in the solution at the column outlet vs ratio of volumes
of the solution (V s ) and ion-exchanger
reaction (see Table 4.3 and Fig. 4.5). Thus, higher breakthrough capacity of the
nanocomposite is due to its improved selectivity toward transition metal ions [23].
This material better removes Ni 2+ ions from water containing also hardness ions.
Regarding the modified weakly acidic resin, its advantage over the pristine resin is
caused by faster sorption and evidently by better selectivity.
Modification decreases breakthrough capacity of the strongly acidic resin toward
BG (due to slower adsorption on the nanocomposite comparing with the pristine
resin) and increases this value for the weakly acidic ion exchanger (this is evidently
caused by higher adsorption capacity and faster adsorption on the nanocomposite).
In order to remove both organic dyes and inorganic anions from mixed solutions
under dynamic conditions, a mixture of the nanocomposites based on strongly and
weakly acidic resins is recommended.
4.7 Conclusions
The modified cation-exchanger contain ZHP particles with size from several
nanometers to several microns. Single nanoparticles are located in pores containing
functional groups; aggregates occupy inert pores. From the formal point of view,
non-aggregated nanoparticles can be considered as a cross-linking agent, which
increases swelling pressure. Swelling pressure provides stretching of transport
pores. As a result, porous structure of the polymer constituent is transformed:
some regions of the polymers, which are able to interact with species, become
unavailable for them. However, embedded ZHP particles evidently expand the range
of pores, where adsorption is possible. This is valid both for BG adsorptions on
weakly and strongly acidic resins. It is the same for Ni 2+ ion sorption on strongly
acidic resins. The particles decrease sorption rate by this manner. At the same time,
strong interaction with Ni 2+ ions is attributed to the weakly acidic resin. Indeed,