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Due to the need to develop technologies for nonregenerative adsorptive separation of ethane, propane, and butane from mixtures (1–5%) with natural gas, the molecular dynamics method was used to calculate the dependence of the adsorbed amounts and separation coefficients of the components of binary mixtures of methane with ethane, propane, and butane on the composition of mixtures, temperature, and pressure.

As an addition to previously obtained data, it has been shown that the adsorption isotherms calculated by the molecular dynamics method for components of light hydrocarbon mixtures in micropores of active carbons and on graphene surfaces are quantitatively described by equations of lattice models with well-coordinated equation parameters.

It has been demonstrated that adsorption isotherms on microporous activated carbons calculated by the method of molecular dynamics at temperatures higher than critical for adsorbents quantitatively coincide with experimental isotherms at calculations in micropores of finite sizes, with the micropore width being chosen in accordance with the theory of micropore volume filling and properly selected force field.

Based on a numerical experiment, it is proven that the Dubinin theory of micropore filling can be extended to adsorption equilibria at supercritical temperatures. The temperature dependences of the main parameters of the theory are refined.

It is shown that an earlier-suggested method of computing isotherms of adsorption of vapor mixtures in a sample pore of active carbon using molecular dynamics can be applied for quantitative computation of adsorption isotherms of components of binary gas mixtures at temperatures higher than critical. It is shown that computed adsorption isotherms of mixture components in micropores and on graphene surfaces are quantitatively described by equations of the lattice model.

We consider our variants of applying a molecular dynamics method to quantitatively calculate adsorption isotherms of gases and vapor and their mixtures on microporous active coals in a wide temperature range (lower and higher than the critical one for adsorptives) and the dependence of adsorbate densities on the width of slit-like micropores.

The possibility of describing isotherms of gas adsorption on flat carbon surfaces by means of lattice model equations and equations of the theory of micropore volume filling has been demonstrated. The obtained results have been compared to data on the adsorption in micropores of active carbon.

Molecular-dynamics calculations confirmed the applicability of the equations of the theory of volume filling of micropores and the lattice model for describing the isotherm of adsorption onto active carbons in a wide range of temperatures below and above the critical values.

Nickel(II), manganese(III), and magnesium(II) porphyrazines are synthesized and investigated as active electrode components of polyvinyl chloride plasticized membranes for ion-selective electrodes (ISE). The potentiometric response of membranes based on metalloporphyrazines doped with 1,3-dihexadecylimidazolium chloride (ionic additive) relative to benzylpenicillin and iodide anions is studied. It is found that the introduction of the ionic additive significantly improves the electrochemical characteristics of the ISE: the slope of the electrode function in benzylpenicillinate solutions is (58 ± 7) mV/dec and cmin = 7 × 10−5 M, and in iodide solutions, (55 ± 2) mV/dec and cmin = 6 × 10−6 M. It is shown that the ISE based on manganese(III) porphyrazine with an ionic additive can be used to determine iodide in Iodinol preparation.