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The present paper deals with permeability of the low-temperature phase of a fullerite using molecular dynamics methods. A discrete model of the material based on “atom−atom” interactions between penetrating components and nodes of the fullerene crystal structure is considered. For the purpose of saving calculation time, when collecting statistical data on passage of molecules and atoms through the porous material under consideration, we found a centrally symmetric distribution of the fullerene action energy and constructed a model of the material based on “smoothed” fullerene particles. The calculations determined permeability of a fullerite membrane containing up to ten planar lattices of the crystal structure. The selectivity factor of the considered membrane, with respect to other components of natural gas is also determined.

This paper investigates the ability of a test molecule to overcome the energy barrier being in the gap between spherical nanoparticles. Three particles make a primitive structural element of composite porous material. The ability of molecules to converge with nanoparticles and then to move through more powerful repulsion field defines the filtration properties of porous materials. This paper presents the investigation of carbon nanoparticles and molecules of helium and methane bombarding them. Calculations proved that methane molecules can not get through three particles if the gap equals to 3.5 nm. For helium molecules this value makes 1.02 nm. These gaps remain the same when the size of nanoparticles increases. Therefore filters for helium separated from natural gas are to have nanopores within the range from 1.02 nm to 3.5 nm.

The integration of the modified LJ-potential allowed revealing the universal effect of the open carbon tube on the molecular objects moving within or proximate to the tube. There has been established that there are modes of the molecule motion without the energy exchange with the atoms of the carbon framing, under which the moving molecules are subjected to the considerable activation in the tube. The potential holes being the sorption zones in fact are localized.