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KACHEVSKII et al.
tive size of substrate molecules [37]. A comparison of
catalytic properties with the structural characteristics of
carriers shows that there exists a well-defined correla-
tion between the activity of the catalysts and the num-
ber of micropores in the carriers. According to our data,
ultradisperse diamond has a well developed mesopo-
rosity with a minimum content of micropores (Table 1).
The catalysts on UDD exhibit the highest activity in the
hydrodechlorination of TCB and HCB (Tables 2 and 3).
Activated carbon from Fluca studied in this work is
characterized by a broad pore size distribution. Apart
from mesopores, this carrier contains micropores less
than nanometer in diameter; their volume is about 30%
of the total volume of pores. The AC carrier largely
contains micropores responsible for its high specific
surface area (1090 cm2/g). As shown above, catalysts
on activated carbons have low activity in the hydro-
dechlorination of chloroorganic substrates, and the
larger the number of micropores in a carrier, the less
active the corresponding catalyst. In all probability, just
micropores are responsible for blocking metal particles
and low catalyst activity.
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RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A Vol. 81 No. 6 2007