ABSTRACT
Experimental Details . . . . . . . . . . . . . . . . . . . . . . . . 362
Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 362
Instrumentation . . . . . . . . . . . . . . . . . . . . . . . . . . . 362
Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363
Results and Discussion . . . . . . . . . . . . . . . . . . . . . . 363
Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . 365
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 366
Variable-temperature diffuse reflectance infrared Fourier transform spectroscopy was used in conjunction
with pyridine desorption studies to assess the acidity of a siliceous surface. An amorphous, porous silica
substrate was investigated. The results contribute to an understanding of the acidic strength and the distri-
bution of acidic sites on this material. A hydrogen-bonding interaction was observed between pyridine and
the surface. Isothermal rate constants and an activation energy for the desorption process are reported and
can be used as direct measures of surface site acidity.
