Potassium‐promoted hydrotalcite‐like material was prepared with potassium nitrate as the K precursor. The highest ever reported CO2 adsorption capacity (1.13 mol kg–1) was obtained at 656 K with p CO 2 = 0.5 bar at humid conditions. A mathematical model was developed and it satisfactorily simulated the adsorption and desorption processes. The stability of the material was tested with repeated adsorption/desorption cycles; the CO2 adsorption capacity decreased around 7 % after ten cycles. In addition, regeneration was performed with temperature swing operation (from 656 K to 708 K), where a complete regeneration was achieved within 60 min, which reduced to half the time required for regeneration under isothermal conditions.

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The adsorption equilibriums of CO 2 , CH 4 , and N 2 pure gases on pitch-based activated carbon beads have been studied using a magnetic suspension microbalance at (293, 303, 333, and 363) K within a pressure range of 0 kPa to 4000 kPa. It is found that experimental adsorption capacities can be successfully described with both the Sips and Multisite Langmuir (MSL) isotherm models. Afterward, binary competitive adsorption breakthrough experiments (CO 2 /CH 4 and CH 4 /N 2 ) at 303 K and adsorption isotherms of gas mixtures under different conditions have been measured. Theoretical calculations from Sips model-based ideal adsorbed solution theory are found to have better agreement with experimental data of competitive binary adsorption than that from MSL model. Promising adsorption selectivity (5.5) between CH 4 and N 2 is obtained at 303 K as the pressure of a binary gas mixture is 100 kPa with y CH4 = 0.5 in the feed. Therefore, the activated carbon beads reported in this study can be considered as a promising adsorbent for CH 4 enrichment from coalbed methane (CH 4 /N 2 ) gas mixture.

A multifunctional K−Ni−Cu−hydrotalcite hybrid material was synthesized for hydrogen production via sorptionenhanced steam reforming of ethanol. The hydrotalcite material was used as support for the incorporation of nickel and copper, both used as active catalytic phases. This material was studied for its catalytic properties for steam reforming of ethanol; it was found that Cu preferentially catalyzes ethanol dehydrogenation and water−gas shift reactions, while Ni is more suitable for acetaldehyde decomposition and steam reforming of methane. It was found that Ni and Cu formed a Ni 0.5 Cu 0.5 alloy with the advantage of ensemble formation. Also, promising carbon dioxide adsorption capacity of the material was obtained. The potassium promoter together with the hydrotalcite material for carbon dioxide adsorption ensured a successful sorptionenhanced reaction process. High-purity hydrogen stream (99.8 mol % on dry basis) was obtained during the prebreakthrough period at 773 K with a water-to-ethanol molar ratio of 10 in the feed; the concentration of hydrogen then decreased to 67.1 mol % after the breakthrough period.