1 It is shown that Bronsted acid sites are mainly formed from the hydroxyl groups in the main channels of mordenite.

2 All fluorinated aluminophosphate sieves have no Bronsted acid site and no Lewis acid site.

3 The application of quantum - chemical studies on the Bronsted acid of zeolites is reviewed.

4 An isomerization of light paraffin is promoted by the interaction between palladium and Bronsted acid site on external surface of mordenite.

5 The formation mechanism of acid sites, mainly the formation mechanism of Bronsted acid sites in HY and REY zeolite as well as Lewis acid sites in matrices and zeolite of FCC catalysts are analyzed.

6 Reduction of nickel ions provides both metal with catalytic function and Bronsted acid.

7 IR results of pyridine adsorption reveal that supported samples have both Bronsted and Lewis acid centers, and 2-propanol dehydration is a Bronsted acid catalysed reaction.