H-Y zeolite modified by a radio-frequency CF4 plasma has been characterized
using X-ray diffraction, nitrogen adsorption, magic angle spinning nuclear
magnetic resonance, ethanol adsorption, energy dispersive X-ray and infrar
ed absorption techniques. The ethanol adsorption measurements indicated tha
t the hydrophobic character of the zeolite was enhanced by the plasma treat
ment. The energy dispersive X-ray experiments showed that the plasma-treate
d zeolite contained 7.91 at% of carbon and 9.93 at% of fluorine. The infrar
ed absorption measurements clarified that replacement of -OH groups by -CF3
or -F groups on the micropore surface of the zeolite was responsible for t
he hydrophobic surface. (C) 2000 Elsevier Science B.V. All rights reserved.