Petroleum Chemistry, Vol.55, No.9, 708-715, 2015
Gas transport properties of LiA type zeolite-filled poly(trimethylsilylpropyne) membranes
The influence of the inorganic filler LiA zeolite on the sorption and transport properties of mixed-matrix membranes based on poly(trimethylsilylpropyne) has been investigated. Isotherms of O-2 and N-2 sorption for the membranes containing up to 30 wt % (16.2 vol %) zeolite are described well in terms of the dual-mode sorption model. It has been found that the solubility of the gases increases with an increase in the filler fraction and nitrogen sorption is preferable in the pressure range of up to 3-5 atm. Gas permeability of the mixed-matrix membranes also increases with increasing filler loading (approximately by 20%) in comparison with the polymer matrix. Membranes selectivity is almost unaffected by zeolite addition. It has been shown that the formation of the mixed-matrix membranes is accompanied by an increase in volume (approximately by 13% at 30 wt % of zeolite loading). The main reason behind the enhancement of O-2 and N-2 permeability through the mixed-matrix poly(trimethylsilylpropyne)/LiA membranes is associated with an additional mass transfer through nanovoids localized around the filler particles.