Study of the Alkylation of Phenol with Methanol on Zn(H)-Exchanged NaY Zeolites

LUIS FRANCISCO GONZALEZ PEÑA; MARÍA EUGENIA SAD; CRISTINA LILIANA PADRÓ; CARLOS RODOLFO APESTEGUÍA

CATALYSIS LETTERS

SPRINGER

Año: 2011 vol. 141 p. 939 - 947

1011-372X

The gas-phase alkylation of phenol withmethanol was studied at 473 K on zeolite NaY exchangedwith Zn+2 (samples Zn(x)NaY) or H+ (samples Na(x)HY)cations. Zeolite NaY contained only weak and mediumLewis acid sites. The addition of Zn+2 formed essentiallystrong Lewis acid sites. In contrast, the exchange of NaYwith H+ generated Brønsted acid sites and decreased thedensity of Lewis acid sites. Zeolite NaY was inactive at473 K, but after its exchange with Zn2+ efficiently promotedthe phenol methylation reaction. Phenol conversionand the selectivities to o- and p-cresols increased with theZn content in the sample. The exchange of Na+ with H+also activated the parent NaY zeolite. At similar phenolconversion levels, Na(x)HY samples formed more anisoleand less cresols than Zn(x)NaY. All the Zn(x)NaY andNa(x)HY samples deactivated on stream, but the catalystactivity decay increased with the exchange degree.