Hl. Zubowa et al., IMPROVEMENT OF CATALYTIC PROPERTIES OF SAPO-31 MOLECULAR-SIEVES BY USING AN ACTIVATED FORM OF SIO2, Applied catalysis. A, General, 110(1), 1994, pp. 27-38
SAPO-31 molecular sieves the synthesis of which is based on different
types Of SiO2 were physico-chemically characterized by X-ray diffracti
on, IR, temperature-programmed desorption of ammonia, Si-29 magic angl
e spinning nuclear magnetic resonance and catalytically investigated i
n the conversion of methanol to lower alkenes and in the isomerization
of n-heptane. The use of ultradispersed SiO2 generated in a capacitiv
ely coupled high frequency plasma (CCP) allowed us to synthesize SAPO-
31 molecular sieves of Bronsted acidities which are higher than with s
amples based on traditional silicon sources. Results of the conversion
of methanol and of the isomerization of n-heptane show that the use o
f plasma-chemically generated silica in the synthesis of SAPO type mol
ecular sieves can be a way to improve their catalytic properties.