Descirbe some features of catalysis by zeolites.

Explanation

(1) Zeolites are shape selective catalysts having honey comb like structure.
(2) They are microporous aluminosilicates with Al – O – Si framework and general formula `M_2x_2`
(3) The reaction taking place in zeolites depends upon the size and shape of the reactant and product molecules as well as upon the pores and cavities of the zeolites.
(4) Zeolites are widely used as catalysts in petrochemical industries for cracking of hydrocarbons and isomerisation. They are also used for removing permanent hardness of water.
(5) e.g., ZSM-5 is a catalyst used in petroleum industry