Study on Modification of NaX Zeolites: The Cobalt (II)-Exchange Kinetics and Surface Property Changes under Thermal Treatment

Table 2

The surface area and pore size of NaX zeolites and Co²⁺-exchanged zeolites: NaX zeolite, untreated sample (0.1-NaCoX-0), and the samples treated at 400°C for 3 h (0.1-NaCoX-1), 500°C for 3 h (0.1-NaCoX-2), 600°C for 3 h (0.1-NaCoX-3), and 700°C for 3 h (0.1-NaCoX-4).

Adsorbents	BET surface area,; /m^2 g^−1	-plot		BJH pore diameter/Å	BJH pore volume,; /cm^3 g^−1
		Micropore surface area,; /m^2 g^−1	External surface area,; /m^2 g^−1
NaX	388	344	45	151.5	0.132
0.1-NaCoX-0	413	340	73	30.4	0.144
0.1-NaCoX-1	395	316	79	42.7	0.172
0.1-NaCoX-2	390	304	85	48.4	0.188
0.1-NaCoX-3	382	302	80	97.0	0.176
0.1-NaCoX-4	341	282	58	92.0	0.177