| نویسندگان | فرشاد فتوحی فر-حدیث بشیری-مسعود همدانیان |
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| تاریخ انتشار | ۲۰۱۶-۱۰-۰۱ |
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| نمایه نشریه | ISI ,SCOPUS |
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چکیده مقاله
The conversion of hexabenzylhexaazaisowurtzitane
(HBIW) to 2,6,8,12-tetraacetyl-4,10-dibenzyl-
2,4,6,8,10,12-hexaazaisowurtzitane (TADB) is the major challenge
in the production of hexanitrohexaazaisowurtzitane
(HNIW) which only proceeds over supported palladium catalyst
in a reductive debenzylation reaction. The catalyst is
quickly deactivated during the debenzylation reaction. In
this study, the change in Pd content in the catalyst during
the reaction was measured. It was demonstrated that a portion
of the palladium particles in the catalyst was leached
during the reaction. The H2 chemisorption isotherm on the
catalyst at 303 K showed that the volume of chemisorbed
H2 on spent catalyst was significantly less than that on
fresh catalyst. The N2 physisorption isotherm on the catalyst
at 77 K revealed that the surface area of spent catalyst was
less than that of fresh catalyst. Moreover, the FESEM-EDS
and TEM images and also wide-angle XRD patterns demonstrated
that the mean sizes of palladium crystallites and
particles in spent catalyst were larger than those in the
fresh catalyst. These results demonstrated that the leaching
of palladium particles and the aggregation of palladium
particles in catalyst play active roles in the deactivation of
catalyst in the debenzylation of HBIW.