Thermodynamics of nitrogen and oxygen sorption on zeolites LiLSX and CaA

Sorption thermodynamics of nitrogen, N-2, and oxygen, O-2, on zeolites LiLSX and CaA were investigated using an isosteric sorption technique [Stud. Surf. Sci. Catal. 83 (1994) 209; Micropor. Mesopor. Mater. 22 (1998) 237] and molecular simulation. The sorption thermodynamic quantities, i.e,, isosteric sorption heat, standard sorption entropy and standard Gibbs free sorption energy, were obtained over entire sorption phase concentration ranges from nearly zero to micropore saturation concentration. The differences in these thermodynamic quantities for the two zeolites of different structures and cation compositions were discussed, and these experimental data were compared with the results from molecular simulation. The advantages of LiLSX over CaA as sorbents for air separation were quantified. (C) 2001 Elsevier Science B.V. All rights reserved.