ALKYLATION OF BENZENE WITH ISOPROPANOL OVER ZEOLITE-BETA

The isopropylation of benzene with isopropanol/propene over Al-, B- and Ga-beta zeolites is reported. The influence of the SiO2/Al2O3 ratio, space velocity, temperature and reactants mole ratios are discussed. The selectivity to cumene is maximum at lower SiO2/Al2O3 ratio and at lower space velocity as well as higher benzene-to-isopropanol ratio. At higher temperatures, cumene isomerizes to n-propyl benzene. Zeolite beta does not exhibit any product shape selectivity among the di-isopropyl benzene isomers. The activity and selectivity of H-Al-beta is compared with other large pore zeolites such as H-mordenite and H-ZSM- 12. The stable activity and higher selectivity over zeolite beta can be attributed to it's highly silicious nature and interconnecting channel system.