Confined space synthesis of chromium–based metal–organic frameworks in activated carbon: Synergistic effect on the adsorption of contaminants of emerging concern from water

Carbon Dioxide Removal from Humid Atmosphere by a Porous Hierarchical Silicoaluminophosphate/Carbon Composite Adsorbent

“…250 °C corresponds to the removal of functional groups (−CO, −OH, etc.) from the surface of the carbon, 20 while the one observed at ca. 450 °C corresponds to decomposition by pyrolysis.…”

“…15 Generally, for systems where the hydrophilicity limits the removal efficiency, the design of hierarchical composites with tailored hydrophobicity could be an alternative 16−19 and confined space synthesis procedures can be used to create a core/shell arrangement where advantages of different adsorbent material phases can be synergistically combined. 20 Based on this, it is reasonable to hypothesize that the in situ growth of a SAPO-34 phase within the meso-and macropores of a commercial activated carbon (AC; the hydrophobic phase), followed by incorporation of extraframework Sr 2+ via ion exchange, would be highly effective for the removal of CO 2 from humid gas streams; the shell material (i.e., AC) can act as a barrier toward water, allowing for better interactions between the selective core (Sr 2+ -SAPO-34) and CO 2 . Furthermore, for closed-loop environments, this approach will also help to simplify the process and operations by reducing energy consumption and perhaps volume requirements, given the hierarchical nature of the composite.…”

“…Nevertheless, although the Sr 2+ -SAPO-34 framework is tolerant to water, its adsorptive capacity is limited due to the competitive adsorption of water since a CO 2 roll-up behavior was observed during fixed-bed adsorption tests . Generally, for systems where the hydrophilicity limits the removal efficiency, the design of hierarchical composites with tailored hydrophobicity could be an alternative − and confined space synthesis procedures can be used to create a core/shell arrangement where advantages of different adsorbent material phases can be synergistically combined . Based on this, it is reasonable to hypothesize that the in situ growth of a SAPO-34 phase within the meso- and macropores of a commercial activated carbon (AC; the hydrophobic phase), followed by incorporation of extraframework Sr 2+ via ion exchange, would be highly effective for the removal of CO 2 from humid gas streams; the shell material (i.e., AC) can act as a barrier toward water, allowing for better interactions between the selective core (Sr 2+ -SAPO-34) and CO 2 .…”

Superior single- and multi-component siloxane removal from water using a faulted silica DON zeolite adsorbent

“…Pure silica zeolite materials (PSZs), which contain only silicon and oxygen atoms, are highly hydrophobic 32,33 and this holds signicant importance for water treatment applications. [34][35][36][37] Moreover, PSZs display exceptional high thermal stability, opening the possibility of being regenerated by thermal swing aer being spent during adsorption. 38,39 PSZs have been extensively tested as adsorbents for gas/vapor [40][41][42][43] and liquid 38,[44][45][46] phase separations.…”