The review focuses on the valorisation of two major greenhouse gases (methane and carbon dioxide) utilising different hybrid plasma reactors where valuable chemicals such as higher hydrocarbons, alcohols, aldehydes, carboxylic acids, etc. are produced.

Yellow-colored methylnitrocatechols (MNC) contribute to the total organic aerosol mass and significantly alter absorption properties of the atmosphere. To date, their formation mechanisms are still not understood. In this work, the intriguing role of HNO (catalytic and oxidative) in the dark transformation of 3-methylcatechol (3MC) under atmospherically relevant aqueous-phase conditions is emphasized. Three possible pathways of dark 3-methyl-5-nitrocatechol and 3-methyl-4-nitrocatechol formation, markedly dependent on reaction conditions, were considered. In the dominant pathway, HNO is directly involved in the transformation of 3MC via consecutive oxidation and conjugated addition reactions (nonradical reaction mechanism). The two-step nitration dominates at a pH around the p K of HNO, which is typical for atmospheric aerosols, and is moderately dependent on temperature. Under very acidic conditions, the other two nitration pathways, oxidative aromatic nitration (electrophilic) and recombination of radical species, gain in importance. The predicted atmospheric lifetime of 3MC according to the dominant mechanism at these conditions (2.4 days at pH 4.5 and 25 °C) is more than 3-times shorter than that via the other two competitive pathways. Our results highlight the significance of a catechol oxidation-conjugated addition reaction in a nighttime secondary nitroaromatic chromophore formation in the atmosphere, especially in polluted environments with high NO concentrations and relatively acidic particles (pH around 3).

Multi-scale modelling of various copper-based catalysts showed how and why different catalysts perform in methanol synthesis via carbon dioxide hydrogenation.

Cu‐based bifunctional materials were examined for carbon dioxide conversion, thus producing the syngas from hydrogen, which can be attained using surplus electrical energy. Catalysts were synthesized by deposition‐precipitation fabrication method, i.e., copper on Al2O3, CeO2, SiO2, TiO2, and ZrO2. To investigate chemical reaction kinetics, the turnover was screened in a parallel high‐throughput packed‐bed reactor system. The results indicated that catalytic pathway mechanisms were affected by the substrate. An optimal supporting oxide may thus contribute to the engineering and intensification of unconventional feedstock processing, e.g., CO2, as well as the design of emerging catalysis routes. The produced synthesis gas may be readily used for basic chemical platforms, such as methanol.

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