Selective alkylation of xylenes by alcohols on zeolite catalysts

Article abstract of DOI:10.1007/BF01430639

The peculiarities of catalytic performance of crystalline aluminosilicates of different types and compositions (X, Y including dealuminated Y′, mordenite, pentasil ZSM-5), as well as of amorphous aluminosilicate catalyst in conversion of xylene + alcohol mixtures were studied. New data were obtained for alkylation of o-xylene with tert-butyl alcohol, concerning controlling the selectivity and stability of the zeolite catalysts in reactions proceeding with the participation of water, including the water evolved during the reaction, in particular by controlling the acidic properties and hydrophobycity of the zeolites. A catalyst ensuring production of 1,2-dimethyl-4-tert-butylbenzene (DMTBB) with a 94% yield and selectivity of alcohol conversion to the target product of 94-97% was developed. The catalyst can be used as the basis for a high-performance and environmentally safe method for the synthesis of DMTBB. The catalysts developed can be also used for selective alkylation of o-xylene by C₃-C₅ alcohols and for alkylation of m-xylene by tert-butyl alcohol.