Abstract: A mesopore molecular sieve having a hydrocarbon group bonded directly to a silicon atom in the metal oxide skeleton constituting the molecular sieve, wherein the content of said hydrocarbon group is from 0.01 to 0.6 mol per mol of the metal oxide. Also disclosed is a process for producing a mesopore molecular sieve having a hydrocarbon atom bonded to a silicon atom in the molecular sieve skeleton, which comprises synthesizing the mesopore molecular sieve, in the presence of a template, from: a silane compound represented by the following formula (1): RnSiX(4−n)  (1) wherein R represents a hydrocarbon group selected from C1-16 hydrocarbon groups and hydrocarbon groups substituted with an N—, O-, S-, P- or halogen-containing group; n represents 1, 2 or 3; and X is selected from C1-6 alkoxy groups, aryloxy groups, a hydroxyl group and halogen atoms and a plurality of X may be the same or different; and a metal oxide and/or a precursor thereof.

Abstract: There is disclosed a method for producing benzene and other useful compounds in high yields and selectivity which comprises hydro-dealkylating alkyl aromatic hydrocarbons in the presence of hydrogen using a catalyst mainly composed of a zeolite 15 to 20 equivalent % of exchangeable cations of which are exchanged with hydrogen ions. The reaction temperature is preferably 500.degree. to 650.degree. C.