MOR catalyst commonly suffers the poor stability in the catalytic synthesis of methyl acetate. It's difficulty to introduce the hierarchical pores by traditional alkali treatment. To overcome this drawback

an ultrasonic alkali treatment was utilized to generate hierarchical MOR via desilication. Multiple analyzing methods

such as XRD

SEM

TEM

pyridine IR and N2 adsorption-desorption

were used to characterize the catalyst structure and the influence of ultrasonic treatment under different alkali concentration on the MOR framework. Acidity

pore structure and catalytic properties were investigated. The results showed that a proper ultrasonic alkali treatment could significantly improve the number of acidic sites

mesopore volume

surface area

pore size distribution

catalytic activity and stability. The DME conversion increased from 35.3% to 44.8%

and the catalyst lifetime was greatly prolonged. However

an excessive alkali concentration seriously destroyed the MOR framework

leading to a rapid decrease on catalyst activity and stability.