1266
CHEPAIKIN et al.
readily be formed in n-propanol oxidation. In this
case, the origin of propanal is associated with the route
in accordance with the ISM. Taking into account the
above, it is possible to approximately determine the
contribution of each of the mechanisms to the forma-
tion of the propane oxidation reaction products.
CONCLUSIONS
i) Thus, a comparative study of the catalytic activ-
(
ity of systems based on rhodium, palladium, and plat-
inum compounds in propane oxidation in an aqueous
acetic acid medium using copper compounds or phos-
phorus–molybdenum–vanadium HPAs as cocatalysts
has been conducted. It has been shown that the sys-
tems exhibit catalytic activity only upon the introduc-
tion of CO as a reducing agent; upon switching from
Cu(II) compounds to HPAs, the activity increases for
the Pt catalysts and decreases for the Rh and Pd sys-
tems. The contribution of the ISM and OSM to the
activation and oxidation of propane has been deter-
mined; it has been found that the role of HPAs in pro-
pane oxidation is similar to that of copper compounds.
These calculations show that, in all the tests, the
contribution of the ISM is extremely significant
(
Tables 1–3, S is the contribution of the ISM). In a
number of tests, isopropanol and acetone dominate
over n-propanol and n-propanal. In this case, the total
activity of the catalyst systems is fairly high; the contri-
bution of the ISM is lower than that of the OSM
(
Table 1, tests 3, 4, 7). In the RhCl –HPA-2 catalyst
3
system, the С Н O yield exceeds the ester yields; the
3
6
(
ii) The use of HPAs as cocatalysts is promising for
designing heterogenized catalyst systems based on
inorganic or polymeric porous supports.
propanal and acetone yields are identical. The contri-
bution of the ISM is 55% (Table 1, test 14). In the Pd-
containing catalyst systems with both Cu(OAc) and
2
HPA-2, the contributions of the OSM and ISM are
approximately identical (Table 2, tests 1, 2, 7, 9). In the
Pt-containing catalyst systems, the best results were
obtained in the case of using HPA-2 as the cocatalyst;
the addition of H SO led to an increase in the activity
CONFLICT OF INTEREST
The authors declare that there is no conflict of interest
regarding the publication of this manuscript.
2
4
and the contribution of the ISM from 38 to 57%
(Table 3, tests 3, 4).
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PETROLEUM CHEMISTRY
Vol. 60
No. 11
2020