Measurement of Acid Site Concentration and Strength in Microporous Solids

4 Measurement of Acid Site Concentration and Strength in Microporous Solids 

As discussed earlier, establishing acid site strengths and concentrations via spectroscopic measurements through the use of organic bases of different 

Strength (Hammett Indicators) is not strictly applicable to microporous solids, although the Hammett scale is a convenient comparative index. As a result, a number of alternative approaches have been taken to determine the concentration, type and strength of acid sites within these solids. Most of these methods give relative scales of acidity, but it is broadly possible to calibrate these acidities to those observed for other acids. The methods fall into three broad categories direct measurements, measurement of interaction with un-reactive probe molecules and the use of catalytic test reactions. 

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