Selective Matrimid Membranes Containing Mesoporous Molecular Sieves

摘要

We have employed mesoporous molecular sieves in polymer membranes in an effort to enhance the permselectivity. The principal advantage of these materials is that the polymer chains can penetrate the pores reducing the nonselective voids that are often observed with inorganic additives. In this study, we have prepared Matrimid~(~R) membranes with various loadings of the all silica molecular sieve DAM-1 (Dallas Amorphous Material) as well as DAM-1 functionalized with amines in the channel wall, to enhance the gas permeability characteristics of a high performance polymer. For all gases tested (N_2, O_2, CO_2, CH_4), the permeability increased in proportion to the wt % of the amine DAM-1 present in the membrane. The addition of the amine DAM-1 resulted in modest ideal O_2/N_2 permselectivity, while the ideal CO_2/CH_4 permselectivity values were >100, depending upon the moisture content of the feed. The ideal CO_2/CH_4 permselectivity values are among the highest for this type of composite membrane. Details of membrane fabrication as well as permeability and permselectivity results will be presented for a range of Matrimid~(~R)/molecular sieve composites.