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of the support. This fact is con¿ rmed by the dependence of the NT on the degree of
application (Table 1). Number of H
2
O
2
moles dissolved per mole of Chl per hour de-
pends only on the substrate ¿ lling by the pigment, but not the presence of irradiation.
In addition, Chl immobilized by non-equilibrium deposition on the surface of silica is
associate in the system of a theoretical monolayer, and in the cases of smaller degrees
of ¿ lling. These associates exhibit catalytic activity in H
2
O
2
decomposition, reducing
at integration associates. Special attention should be paid to the fact that for Chl with
the degree of ¿ lling of 1.92 mmol/g photoactivity was lower than activity in darkness
by 30%. Probably, in this case Chl excess on the carrier surface was photodestructed
quickly. It explains the negative value of Ș. We showed that the Chl photodestruction
was accelerated for a highly aggregated state [12]. Most likely, that for systems with
a
= 1.92 mol/g the interaction of Chl-Chl predominates over the coordination of Chl
with the OH-groups of silica. The results indicate the inef¿ ciency of Chl coating large
degrees using for photocatalytic reactions.
FIGURE 1
Semi-logarithmic linear anamorphoses of kinetic curves of ɇ
2
Ɉ
2
decomposition
photocatalyzed by adsorbed Chl. The value of adsorption is 1.92 (
1
), 0.57 (
2
), and 0.23 ȝmol/g
(3). Initial concentration of hydrogen peroxide is [ɇ
2
Ɉ
2
]
0
= 0.15 mol/l.
In the case of equilibrium adsorption for system with
a
= 0.47 mol/g, correspond-
ing premonolayer substrate surface coating [13], the activity of Chl under light was
twice higher than in the dark. Obviously, in this system packing of Chl molecules was
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