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The adsorption equilibrium of carbon dioxide (CO 2 ), carbon monoxide (CO), nitrogen (N 2 ), methane (CH 4 ), and hydrogen (H 2 ), was studied at 303 K, 323 K, and 343 K, and pressures up to 7 bar, in titanium based MOF granulates, amino-functionalized titanium terephthalate MIL-125(Ti)_NH 2 . The affinity of the different adsorbates towards the adsorbent presented the following order: CO 2 > CH 4 > CO > N 2 > H 2 from the most adsorbed to the less adsorbed component. Subsequently, adsorption kinetics and multicomponent adsorption equilibrium were studied by means of single, binary and ternary breakthrough curves at 323 K and 4.5 bar with different feed mixtures. Both studies are complementary, and aim the syngas purification for two different applications, hydrogen production and H 2 /CO composition adjustment to be used as feed in the Fisher-Tropsch processes. The isosteric heats were calculated from the adsorption equilibrium isotherms and are 21.9 kJ mol -1 for CO 2 , 14.6 kJ mol -1 for CH 4 , 13.4 kJ mol -1 for CO, and 11.7 kJ mol -1 for N 2 . In the overall pressure and temperature range the adsorption equilibrium isotherms were well regressed against the Langmuir model. The multicomponent breakthrough experimental results allowed validation of the adsorption equilibrium predicted by the multicomponent extension of the Langmuir isotherm, and validation of the fixed-bed mathematical model. To conclude, two pressure swing adsorption cycles were designed and performed experimentally, one for hydrogen purification from a 30%/70% CO 2 /H 2 mixture (hydrogen purity was 100 % with recovery of 23.5 %), and a second PSA cycle to obtain a light product with a H 2 /CO ratio between 2.2 and 2.4 to feed to a Fischer-Tropsch processes. The experimental cycle produced a light stream with a H 2 /CO ratio of 2.3, and a CO 2 enriched stream with 86.6 % purity as heavy product. The CO 2 recovery was 93.5 %

An essential line of worldwide research towards a sustainable energy future is the materials and processes for carbon dioxide capture and storage. Energy from fossil fuels combustion always generates carbon dioxide, leading to a considerable environmental concern with the values of CO2 produced in the world. The increase in emissions leads to a significant challenge in reducing the quantity of this gas in the atmosphere. Many research areas are involved solving this problem, such as process engineering, materials science, chemistry, waste management, and politics and public engagement. To decrease this problem, green and efficient solutions have been extensively studied, such as Carbon Capture Utilization and Storage (CCUS) processes. In 2015, the Paris Agreement was established, wherein the global temperature increase limit of 1.5 °C above pre-industrial levels was defined as maximum. To achieve this goal, a global balance between anthropogenic emissions and capture of greenhouse gases in the second half of the 21st century is imperative, i.e., net-zero emissions. Several projects and strategies have been implemented in the existing systems and facilities for greenhouse gas reduction, and new processes have been studied. This review starts with the current data of CO2 emissions to understand the need for drastic reduction. After that, the study reviews the recent progress of CCUS facilities and the implementation of climate-positive solutions, such as Bioenergy with Carbon Capture and Storage and Direct Air Capture. Future changes in industrial processes are also discussed.

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New hybrid materials, shaped by extrusion, suitable to be used in the electric swing adsorption (ESA) process for CO2 capture, were developed. Pellets were produced using activated carbon (AC) and zeolite 13X (with four different compositions). An extensive study was carried out to determine the characterization and adsorption equilibrium of CO2 and N2. The CO2/N2 selectivity of the pellets was 62.8, 41.9, 24.6, and 12.2 at 1.5 bar, and 298 K, respectively, for the 30% AC–70% 13X, 50% AC–50% 13X, 70% AC–30% 13X, and 100% AC pellets, considering multicomponent adsorption of 20% CO2 of in N2. All pellets demonstrated a temperature increase when electric current was applied, except for the 30% AC–70% 13X pellets, concluding that these were not suitable for the ESA process because heat regeneration is used and also that there is a percolation threshold limit. Binary breakthrough curves developed using 50% AC–50% 13X pellets with electrification have proven that the heating by the Joule effect resulted in significantly faster adsorbent regeneration.

The synthesis of 1,1‐diethoxybutane (DEB) through the acetalization reaction between ethanol and butyraldehyde was studied in a fixed‐bed adsorptive reactor packed with Amberlyst‐15 wet. The miscibilities of reactants and water were evaluated and breakthrough experiments with nonreactive pairs of ethanol‐water and ethanol‐DEB were performed. The parameters of the isotherms were fitted by a Langmuir competitive model. Synthesis of the acetal was carried out with mixtures of ethanol and butyraldehyde at different molar ratios. The dynamic behavior of the fixed‐bed adsorptive reactor was described by a mathematical model developed taking into account the reaction kinetics, adsorption mechanisms, mass transfer resistances, and velocity variations.

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