A study on acid sites related to activity of nanoscale ZSM-5 in toluene disproportionation

The acid amount and acid strength of nanoscale HZSM-5 and modified HZSM-5 were studied. It has been shown that only acid sites with acid strength H0 ⩽ +2.27 are related to the catalytic activity in toluene disproportionation. The acid sites with acid strength H0 ⩽ −3.0 are easily passivated and the acid site with acid strength −3.0 < H0 ⩽ +2.27 are the body of valid acid site in modified HZSM-5. The concentration of acid site did not linearly relate to the reactivity in toluene disproportionation.