Hydrogen sulfide removal from small quantities of gas such as biogas or landfill gas is usually carried out via technologies based on its adsorption onto solid sorbents. Biogas or landfill gas has a high moisture content; thus, for H 2 S removal, nonpolar-activated carbon is the most suitable sorbent. However, the adsorption capacity of common activated carbon for H 2 S is small. Therefore, sorbents that have been properly impregnated are often used because they react with H 2 S to form various products. This leads to great differences among the different sorbents regarding the adsorption capacity and H 2 S removal efficiency. Various commercially available impregnated sorbents for H 2 S capture were tested at different reaction conditions (type of impregnation agent, gas moisture content, and oxygen presence in gas). The test results showed that the H 2 S adsorption capacity of the sorbents is strong depending on the reaction conditions. To properly select a suitable sorbent for a specific industrial application, it is necessary to know the gas composition, in particular, oxygen and water content.

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Potassium modified acid–base bifunctionalized MgAl-SBA-15 for mild aldol condensation of furfural and acetone to high-quality jet-fuel range or chemical intermediates.

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The formation of a polycrystalline 3D gallium–imidazole framework (MOF) was closely studied in three steps using ssNMR, XRPD, and TGA. In all steps, the reaction products show relatively high temperature stability up to 500 °C. The final product was examined by structural analysis using NMR crystallography combined with TG and BET analyses, which enabled a detailed characterization of the polycrystalline MOF system on the atomic-resolution level. 71Ga ssNMR spectra provided valuable structural information on the coexistence of several distinct gallium species, including a tunable liquid phase. Moreover, using an NMR crystallography approach, two structurally asymmetric units of Ga­(Im6)6– incorporated into the thermally stable polycrystalline 3D matrix were identified. Prepared polycrystalline MOF material with polymorphic gallium species is promising for use in catalytic processes.