Zeolites: Promised Materials for the Sustainable Production of Hydrogen

Table 1

Zeolite classification according to the pore size.

Zeolite classification	Number of the oxygen atoms in the opening ring	Pore diameter (Å)	Example of zeolites
Small pore	8	3<𝜃<5	Erionite, A, ITQ-3
Medium pore	10	5<𝜃<6	ZSM-5, ZSM-11, ITQ-1
Large pore	12	6<𝜃<9	X, Y, Beta, Ω, mordenite, ITQ-7, ITQ-21
Extralarge pore	18	9<𝜃	MCM-9, VIP-5, ITQ-33