Several catalytic membranes have been studied, with different loadings and:
radial distribution of the catalytic material. Two types of catalytic memb
ranes have been prepared on top of alumina supports: (a) V/MgO membranes, w
here MgO was deposited in the support pores before impregnation with V, and
(b) V/Al2O3 membranes, where the alumina supports were impregnated with a
boehmite sol before V deposition. In both cases the introduction of V was c
arried only from the internal side of the porous tube, and using short impr
egnation times, in order to obtain a radial distribution of active material
.
The membranes prepared have been tested under reaction conditions, giving y
ields to propene of up to 15%. It was found that the best V/MgO membranes a
re more selective but less active than the best V/Al2O3 membranes. (C) 2000
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