Siberian Federal University

The microspherical membranes based on narrow fraction of cenospheres with high permeability to helium and high selectivity for He/Ne were recovered from cenosphere concentrate from Ekibastuz coal combustion. Acid leaching of the obtained microspherical membranes by 8.6M HNO3 contribute to microporosity development in their shell (volume percentage of the micropore with predominant sizes of 5, 6.4 and 13 Å was increased from 6.7 to 34.0 vol. %).This led to increase in helium permeation at T=298 K about to 2 times, i.e. up to a value of 2.27·10-18 (mol·m)/(m2·sec·Pa). The obtained microspherical membranes are characterized by high selectivity α(He/Ne)=170 at 553K, and exceed the synthetic glass hollow microspheres 3M K37 Glass Bubbles (3MTM, USA) in helium permeation to 37-57 times, and the polymeric membrane material –(poly)sulphone in selectivity for He/Ne to 34-52 times