Side-chain alkylation of toluene with methanol on Cs-exchanged NaY zeolites: effect of Cs loading

The side-chain alkylation of toluene with methanol was studied on Cs-exchanged NaY zeolites containing up to 31% Cs (exchange degree, ED, up to 70%). Formation of styrene and ethylbenzene was significant only on Na(Cs)Y zeolites of ED higher than about 40%. Bimolecular side-chain alkylation reaction would require a proper surface geometric configuration of Oδ−-Cs+ pairs that is achieved only on Cs-rich zeolites. In contrast, the side reaction forming carbon monoxide from methanol increases monotonically with increasing ED because it is essentially controlled by the basicity of the oxygen lattice.