| The regular micro pore
structure of zeolites is probably responsible for the selectivity
which makes them so useful. |
|
Before being used for cat cracking
zeolite Y is converted to its acid form by ion exchange. The cations
are replaced by hydrogen ions.
|
| Click
for more information on zeolites |
| The Bronsted acid sites catalyse
the cracking reactions, with the reactants held in the large network
of pores in the zeolite. |
| Zeolites can be 10000 times more active as
cracking catalysts than silica/alumina. But commercially the cracking
rate is matched to the catalyst regeneration rate . The zeolite
is dispersed on SiO2-Al2O3, rather than being used pure. |
|
