A system and method for acid gas separations using porous frameworks of metal atoms coordinatively bound to polytopic linkers that are functionalized with basic nitrogen ligands that expose nitrogen atoms to the pore volumes forming adsorption sites. Adjacent basic nitrogen ligands on the metal-organic framework can form an ammonium from one ligand and a carbamate from the other. The formation of one ammonium carbamate pair influences the formation of ammonium carbamate on adjacent adsorption sites. Adsorption of acid gas at the adsorption sites form covalently linked aggregates of more than one ammonium carbamate ion pair. The acid gas adsorption isotherm can be tuned to match the step position with the partial pressure of acid gas in the gas mixture stream through manipulation of the metal-ligand bond strength by selection of the ligand, metal and polytopic linker materials.

The invention relates to a heat exchanger having at least one sorption duct in which is arranged a sorption medium and through which a fluid can be made to flow, characterized in that the heat exchanger also contains at least one catalyst with which a fuel can be converted exothermically such that at least some of the resulting heat can be conveyed to the sorption medium. The invention also relates to a method for heating and/or conditioning a gas stream, having at least the following steps: supplying a gas stream, containing multiple different components, into a sorption duct in which is arranged a sorption medium, such that at least one component is bound in the sorption medium, and supplying and exothermically converting at least one fuel under the action of a catalyst, such that at least one component of the gas stream is expelled from the sorption medium.

An adsorption material is disclosed that comprises a metal-organic framework and a plurality of Hgands. The metal-organic framework comprising a plurality of metal ions. Each respective ligand in the plurality of ligands is amine appended to a respective metal ion in the plurality of metal ions of the metal-organic framework. Each respective ligand in the plurality of ligands comprises a substituted 1,3-propanediamine. The adsorbent has a CO2 adsorption capacity of greater than 2.50 mmol/g at 150 mbar CO2 at 40° C., Moreover, the adsorbent is configured to regenerate at less than 120° C. An example ligand is diamine 2,2-dimethyl-1,3-propane-diamine. An example of the metal-organic framework is Mg2(dobpdc), where dobpdc.sup.4− is 4,4′-dioxidobiphenyl-3,3′-dicarboxylate. Example applications for the adsorption material are removal of carbon dioxide from flue gas and biogasses.

To reduce loss due to water evaporation and to efficiently release moisture from a moisture absorbing portion, in the humidity controller according to the present invention, a moisture absorbing portion (2) is formed to include at least two gel sections each with a different thermal conductivity and to release absorbed moisture from an exposed surface (31) that is a specific region exposed outside and that is disposed on the surface opposite to a heater (5) on the basis of heating by the heater (5).

Disclosed are MOFs containing nucleophilic transition metal hydroxide (M-OH) groups. In certain embodiments, these MOFs can include a plurality of metal ions, each coordinated with one or more hydroxide ligands and one or more backbone ligands. In certain embodiments, the MOFs can comprise Kuratowski cluster-based secondary building units (SBUs). These MOFs can exhibit excellent performance for low pressure CO.sub.2 capture via a CO.sub.2/HCO.sub.3.sup.− fixation mechanism in which cooperative inter-cluster hydrogen bonding interactions enhance CO.sub.2 capture performance. Also provided are methods of making MOFs including one or more metal hydroxide moieties, as well as methods of using these MOFs to capture an acidic gas (e.g., CO.sub.2, SO.sub.2, NO.sub.2, or acetylene).

Processes for regenerating sorbents at high temperatures, and associated systems, are generally described.

A nucleophilic substitution reaction to crosslink cyclodextrin (CD) polymer with rigid aromatic groups, providing a high surface area, mesoporous CD-containing polymers (P-CDPs). The P-CDPs can be used for removing organic contaminants from water. By encapsulating pollutants to form well-defined host-guest complexes with complementary selectivities to activated carbon (AC) sorbents. The P-CDPs can rapidly sequester pharmaceuticals, pesticides, and other organic micropollutants, achieving equilibrium binding capacity in seconds with adsorption rate constants 15-200 times greater than ACs and nonporous CD sorbents. The CD polymer can be regenerated several times, through a room temperature washing procedure, with no loss in performance.

Provided herein are metal organic frameworks comprising metal nodes and N-donor organic ligands which have high selectivity and stability in the present of gases and vapors including H.sub.2S, H.sub.2O, and CO.sub.2. Methods include capturing one or more of H.sub.2S, H.sub.2O, and CO.sub.2 from fluid compositions, such as natural gas.

Certain embodiments described herein are directed to systems and methods that can be used to analyze species in a fluid stream. In some configurations, a sorbent tube effective to directly sample aromatics and/or polyaromatics in a fluid stream is described.

The purpose of the present disclosure is to provide a method for regenerating a highly water-absorbing polymer that has been deactivated by an acid, the method enabling formation of a highly water-absorbing recycled polymer having predetermined water absorption properties. The regeneration method according to the present disclosure is configured as follows. This method regenerates a highly water-absorbing polymer that has been deactivated by an acid into a highly water-absorbing recycled polymer having predetermined water absorption properties. The method includes: a preparation step (S1) for preparing a highly water-absorbing polymer which has an acid group and which has been deactivated by an acid; a highly water-absorbing recycled polymer-forming step (S3) for adding an alkali metal ion source, which can supply an alkali metal ion, to a regeneration-use aqueous solution that contains the highly water-absorbing polymer that has been deactivated by an acid, and forming the highly water-absorbing recycled polymer in a wet state from the highly water-absorbing polymer that has been deactivated by the acid; and a drying step for drying the highly water-absorbing recycled polymer in a wet state and forming the highly water-absorbing recycled polymer having the predetermined water absorption properties.