Methanol conversion on high-silica zeolites with different alumosilicate modules and prepared in different ways

High-silica zeolites in the H-form that differ in the SiO₂/Al₂O₃ ratio and the method of synthesis, have similar acidity spectra but different distributions of the acidic centers with respect to strength. A symbatic change in the concentration of the strongly acidic centers and of the degree of conversion of methanol has been observed, as well as a change in selectivity for C₂–C₄ aliphatic and aromatic hydrocarbons. It has been established that the stages of dehydration of methanol and dimethyl ether, and of aromatization and alkylation occur on strongly acidic centers of high-silica zeolites, and polymerization reactions on weakly acidic centers.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 23, No. 3, pp. 380–383, May–June, 1987.