The first commercial hollow fiber and flat sheet gas separation membranes were produced in the late 1970s from the glassy polymers polysulfone and poly(vinyltrimethyl silane), respectively, and the first industrial application was hydrogen recovery from ammonia purge gas in the ammonia synthesis loop. Membranes based on glassy polymers (polysulfone, cellulose acetate, polyimides, substituted polycarbonate, and poly(phenylene oxide)) are currently used in various industrial processes, such as hydrogen purification, nitrogen production, and natural gas treatment. However, the glassy polymers are in a non-equilibrium state; therefore, these polymers undergo a process of physical aging, which is accompanied by the spontaneous reduction of free volume and gas permeability over time. The high free volume glassy polymers, such as poly(1-trimethylgermyl-1-propyne), polymers of intrinsic microporosity PIMs, and fluoropolymers Teflon^® AF and Hyflon^® AD, undergo significant physical aging. Herein, we outline the latest progress in the field of increasing durability and mitigating the physical aging of glassy polymer membrane materials and thin-film composite membranes for gas separation. Special attention is paid to such approaches as the addition of porous nanoparticles (via mixed matrix membranes), polymer crosslinking, and a combination of crosslinking and addition of nanoparticles.

In this study approaches for chemical conversions of the renewable compounds 1,2-propanediol (1,2-PD) and 2,3-butanediol (2,3-BD) that yield the corresponding cyclic ketals and glycol ethers have been investigated experimentally. The characterization of the obtained products as potential green solvents and gasoline components is discussed. Cyclic ketals have been obtained by the direct reaction of the diols with lower aliphatic ketones (1,2-PD + acetone → 2,2,4-trimethyl-1,3-dioxolane (TMD) and 2,3-BD + butanone-2 → 2-ethyl-2,4,5-trimethyl-1,3-dioxolane (ETMD)), for which the ΔH⁰_r, ΔS⁰_r and ΔG⁰_r values have been estimated experimentally. The monoethers of diols could be obtained through either hydrogenolysis of the pure ketals or from the ketone and the diol via reductive alkylation. In the both reactions, the cyclic ketals (TMD and ETMD) have been hydrogenated in nearly quantitative yields to the corresponding isopropoxypropanols (IPP) and 3-sec-butoxy-2-butanol (SBB) under mild conditions (T = 120–140 °C, p(H₂) = 40 bar) with high selectivity (>93%). Four products (TMD, ETMD, IPP and SBB) have been characterized as far as their physical properties are concerned (density, melting/boiling points, viscosity, calorific value, evaporation rate, Antoine equation coefficients), as well as their solvent ones (Kamlet-Taft solvatochromic parameters, miscibility, and polymer solubilization). In the investigation of gasoline blending properties, TMD, ETMD, IPP and SBB have shown remarkable antiknock performance with blending antiknock indices of 95.2, 92.7, 99.2 and 99.7 points, respectively.

The etherification of glycerol with -butyl alcohol at 140°C in the presence of sulfonated cation-exchange resins and zeolite catalysts in an autoclave reactor has been studied. It has been shown that styrene—divinylbenzene ion-exchange resins are effective catalysts for the production of glycerol -butyl ethers: the glycerol conversion is about 98% with an -butyl ether selectivity of about 88 mol % (140°C, 5 h, 5 wt % Amberlyst 36 catalyst, and 10 wt % glycerol in -butanol). Zeolites Y and β in the H form exhibit comparable specific activity (glycerol conversion of no more than 25% under similar conditions) in combination with high selectivity for glycerol di--butyl ethers (up to 28%).

The hydrocracking reaction of a pyrolysis fuel oil fraction using in situ generated nano-sized NiWS-sulfide catalysts is studied. The obtained catalysts were defined using X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The features of catalytically active phase generation, as well as its structure and morphology were considered. The catalytic reactivity of in situ generated catalysts was evaluated using the hydrocracking reaction of pyrolysis fuel oil to obtain a light fraction to be used as a feedstock for benzene, toluene, and xylene (BTX) production. It was demonstrated that the temperature of 380 °C, pressure of 5 MPa, and catalyst-to-feedstock ratio of 4% provide for a target fraction (IPB −180 °C) yield of 44 wt %, and the BTX yield of reaching 15 wt %.