HETEROGENIZATION OF HOMOGENEOUS PERFLUOROTHIOPHENE Rh(I) COMPLEX AND EXAMINATION OF HYDROGENATION ACTIVITY IN scCO2 MEDIA
Abstract
Rhodium(I) complex of perfluorinated thiophene
ligand was synthesized and heterogenized over the modified silica support. SEM,
XRF, TGA and BET methods were used for the characterization of the
heterogenized catalyst (SiAPTES-RhL). Heterogenization of catalyst and the catalytic
activity tests were carried out in scCO2 as a greener alternative to
traditional reaction media. The catalytic activities of complex were
investigated in hydrogenation reactions of some alkenes such as styrene,
1-octene and cyclohexene. 100% ethyl benzene conversion was observed at 370 K,
10 bar H2 and 1900 psi total pressure in styrene hydrogenation.
Also, it was found that the catalyst remains active at least throughout ten
cycles. Similarly, the activity of the catalyst in the hydrogenation of
1-octene and cyclohexene was investigated. For 1-octene, 100% n-octan selectivity
was obtained at 370 K and 10 Bar H2. The catalyst was found to be
effective at 370 K while the activity was low at 350 and 360 K in cyclohexen
hydrogenation. When compared with the homogenous system, the heterogenized
catalyst had more activity and selectivity and also reusability without losing
its activity
Keywords
Heterogenized homogeneous catalyst,Silica support rhodium complex,scCO2
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