Mixed ion exchanged Li-Ca-LSX were prepared respectively from the starting materials Li-LSX and Ca-LSX and effects of the difference on ion exchanging degree, ion location and adsorption properties were investigated via the measurements of ICP-AES, 7Li MAS NMR, 23Na MAS NMR and static adsorption method. The results show that the Li-Ca-LSX prepared from Ca-LSX as the starting material reaches the exchange maximum by 31.5% and the best properties, namely the specific adsorption capacity at 36.4mL/g for N2 and 5.0mL/g for O2; and the N2/O2 adsorption selectivity at 12.4. From the results of NMR, it is found that excepting the well-known site SIII, some Li+ locating at the site SI’ can also affect significantly on the adsorption properties of LSX.
LI Zhi-Liang
,
ZHI Jian-Ping
,
ZHANG Yu-Lin
. Effects of Different Starting Materials on Preparation and Adsorption Properties of the Mixed Li+ and Ca2+ Exchanged Low Silica X-type Zeolites(LSX)[J]. Journal of Inorganic Materials, 2008
, 23(5)
: 975
-980
.
DOI: 10.3724/SP.J.1077.2008.00975
[1] Yang R T. Recent advances and new horizons in gas adsorption with a focus on new sorbents. Topical Conference on Seperation Technology, New York, 1997.14. [2] Mckee D W. Sepration of an Oxygen-Nitrogen Mixture. US 3 140 933. 1964.
[3] Chao C C. Process for Separating Nitrogen from Mixture Thereof with Less Polar Substances US 4 859 217. 1989. [4] Kirner J F. Nitrogen adsorption with highly Li exchanged X-zeolites with low Si/Al ratio. US 5 268 023. 1993.
[5] 关莉莉, 段连运, 谢有畅(GUAN Li-Li, et al). 无机材料学报(Journal of Inorganic Materials), 2005, 20 (2): 503--507.
[6] Huston N D, Regee S U, Yang R T. AIChE, 1999, 45 (4): 724--734.
[7] Coe C G, Kirner J F, Pierantozzi R R, et al. Nitrogen Adsorption with a Ca and or Sr Exchanged Lithium X Zeolite. US 5 152 813.1992. [8] Kuhl G H. Zeolites, 1987, 7 (5): 451--457.
[9] Mortier W J, Bosmams H J, Uytterhoeven J B. J. Phys. Chem., 1972, 76 (5): 650--656.
[10] Feuerstein M, Lobo R F. Chem. Mater., 1995, 2 (1): 43--51.
[11] Feurestein M, Engelhardt G, McDaniel P L. Microp. Mesop. Mater., 1998, 26: 27--35.
[12] Jasra R V, Choudary N V, Bhat S G T. India. J. Chem., 1995, 34 (1): 15--21.
[13] Sherry H S. Cation Exchange on Zeolites. Proceedings of the 2nd International Conference on Zeolite. Worcester, 1970. 350. [14] 崔邑诚, 张爱民, 董家禄, 等. 化学学报, 2003, 61 (3): 350--353.