Some sorptive and catalytic properties of zeolite Nu—10

Abstract

Characterization of the pore structure of zeolite Nu—10 was performed by measuring the rates and extents of adsorption of a range of molecules of different kinetic diameter. The results were indicative of a pore structure similar to that found in ZSM—5, comprising apertures of diameter 0.6 nm. Results obtained during methanol conversion, however, revealed a cut-off in the hydrocarbon product distribution at C 6, which is indicative of a more constrained environment within the pore structure of Nu—10 relative to that in ZSM—5. This suggests that Nu—10 is devoid of large channel intersections of the type found in ZSM—5 and other pentasil zeolites. The preferential formation of trans-but-2-ene observed during but-1-ene isomerization over Nu—10 is consistent with a pore structure of this type; the slower diffusion of the larger cis-but-2-ene isomer within the intracrystalline pore structure giving rise to secondary cis-trans isomerization and formation of the thermodynamically favoured trans-but-2-ene.