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• Two-component ionogels containing clay minerals and ionic liquids were prepared. • The thermal behavior of the synthesized ionogels and pristine ILs was investigated using DSC and TG techniques. • A confinement effect was revealed in the studied materials. • The glass-transition temperature shifted towards higher temperatures with the introduction of aluminosilicate. • The characteristic temperatures of thermal decomposition of ionogels were lower than those for the pristine ILs. Two-component ionogels containing clay minerals such as montmorillonite K 10 (Mnt- K 10), bentonite (Bent), and halloysite (Hly), as well as imidazolium-based ionic liquids (ILs) were prepared in present work. The ILs that were used in the synthesis included a bis(trifluoromethylsulfonyl) imide anion (TFSI-) and various cations: 1-ethyl-3-methylimidazolium (EMIm+), 1-propyl-3-methylimidazolium (PMIm+), 1-butyl-3-methylimidazolium (BMIm+), and 1-butyl-2,3-dimethylimidazolium (BDMIm+). The thermal behavior of the synthesized ionogels and neat ILs was investigated using differential scanning spectroscopy (DSC) and thermogravimetric analysis (TG). It was found that the thermograms of PMImTFSI, BMImTFSI, and BDMImTFSI showed inflections corresponding to glass-transition, which shifted towards higher temperatures with the introduction of aluminosilicate. The largest shifts compared to the neat ILs were observed for IL/Bent ionogels. It was assumed that the identified differences in the thermal behavior between the neat and clay-entrapped ILs (confinement effect) are associated with an increased role of ion-wall interactions compared to ion-ion interactions. When studying the thermal stability of the materials under consideration, two opposite trends were noted. On the one hand, the characteristic temperatures of thermal decomposition of the synthesized ionogels were lower than those for the neat ILs. But on the other hand, when introducing aluminosilicate into any IL, a decrease in the maximum rate of thermal decomposition was observed in accordance with series of IL > IL/Mnt- K 10 > IL/Hly > IL/Bent. [ABSTRACT FROM AUTHOR]

• Polystyrene/montmorillonite composite films were prepared via solution cast technique. • Plasma treatment of the produced films was carried out in low-pressure air plasma. • The water contact angle on the composite surface decreased after plasma treatment. • Plasma treatment of the composite led to an increase in MB adsorption efficiency. Polystyrene/montmorillonite (PS/MMT) composite films with high adsorption activity were prepared via solution intercalation technique followed by treatment of composite films in low-pressure air plasma. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and scanning electron microscopy were used to investigate the impact of plasma on the elemental composition and morphology of the composite surface. It was revealed that plasma treatment of the PS/MMT composite led to an increase in wettability and adsorption performance. The removal kinetics of methylene blue dye from aqueous solutions was experimentally studied. It was determined that plasma processing of the composite resulted in a significant improvement of the MB adsorption process: the initial rate of the process increased by 4 times (from 1.2 × 10−8 to 4.8 × 10−8 mol/(g•min)). Adsorption kinetic curves are obeyed the pseudo-second order reaction equation. [Display omitted] [ABSTRACT FROM AUTHOR]

• Thermal depolymerization of polystyrene in the hydrocarbon medium was studied. • Maximum styrene yield was 84.4% in LCO at 500 °C and the vapor residence time 2.61 s. • Formation of a styrene dimer in the hydrocarbon medium is inhibited. • Depolymerization products seem suitable for further styrene monomer production. Data from the thermal depolymerization of polystyrene in a highly aromatic hydrocarbon medium (light and heavy cycle oil) have been obtained. The influences of the reaction conditions on the conversion and selectivity have been studied. The maximum yield of styrene obtained in the present work is 84.4% at a polymer conversion of 93.8% in light cycle oil under the following conditions: temperature: 500 °C, vapor residence time: 2.61 s, polymer concentration: 15%. The styrene yield obtained is higher than has been previously reported in the scientific literature. The high selectivity of styrene in the depolymerization reaction can be explained by the fact that under the reaction conditions studied, the formation of styrene dimers in the hydrocarbon medium is inhibited. [ABSTRACT FROM AUTHOR]