Gas separation membranes as may be used in separating gaseous materials from one another and methods of forming the membranes are described. The separation membranes include polymer-grafted nanoparticles (GNPs) as a platform and a relatively small amount of free polymer. The free polymer and the polymer grafted to the nanoparticles have the same chemical structure and similar number average molecular weights. The gas separation membranes can exhibit high ideal selectivity and can be used in a variety of applications, such as carbon capture.

The present disclosure relates to a membrane apparatus for selectively retaining and releasing target cations, such as lithium. The membrane apparatus comprises a cation exchange layer and an anion exchange layer that are coupled and configured for hydraulic communication with sufficient permselectivity to facilitate water splitting under an applied voltage. The cation exchange layer comprises a sorbing agent that has a target cation binding coefficient that is less than its hydrogen ion binding coefficient such that it may be efficiently regenerated by in situ produced hydrogen ions. Electrically regenerated ion exchange devices and methods are also described.

Water permeable coated substrates comprising a polymeric substrate in contact with a coating comprising a plurality of particles and a cross-linked polymer are disclosed. Uses of the coated substrates, particularly for water filtration are also disclosed.

New carbon nanomaterials, preferably titanium carbide-derived carbon (CDC) nanoparticles, were embedded into a polyamide film to give CDC/polyamide mixed matrix membranes by the interfacial polymerization reaction of an aliphatic diamine, e.g., piperazine, and an activated aromatic dicarboxylate, e.g., isophthaloyl chloride, supported on a sulfone-containing polymer, e.g., polysulfone (PSF), layer, which is preferably previously prepared by dry/wet phase inversion. The inventive membranes can separate CO.sub.2 (or other gases) from mixtures of CO.sub.2 and further gases, esp. CH.sub.4, based upon the generally selective nanocomposite layer(s) of CDC/polyamide.

The present disclosure relates to sustainable and green polylactic acid-based membranes embedded with self-assembled positively and negatively charged multiwalled carbon nanotube/graphene oxide nanohybrids for the removal of organic and inorganic nutrients from wastewater, and methods of synthesis of the same. A positively charged multi-walled carbon nanotube/graphene oxide (f-MWCNT/GO) nanohybrid-based mixed matrix membrane can comprise a self-assembled multi-walled carbon nanotube and graphene oxide (f-MWCNT/GO) nanohybrid, and a polylactic acid (PLA) membrane matrix. The f-MWCNT/GO nanohybrid is integrated into the PLA membrane matrix to form the positively charged mixed matrix membrane. A negatively charged multi-walled carbon nanotubes (f-GO/MWCNTs-COOH) nanohybrid-based mixed matrix membrane can comprise a positively charged Graphene Oxide and negatively charged multi-walled carbon nanotube-COOH (f-GO/MWCNTs-COOH) nanohybrid, and a polylactic acid (PLA) membrane matrix. The f-GO/MWCNTs-COOH nanohybrid is integrated into the PLA membrane matrix to form the negatively charged mixed matrix membrane.

A CO.sub.2 separation membrane can include a CO.sub.2-philic layer comprising one or more mobile CO.sub.2 carriers and one or more immobile CO.sub.2 carriers and a blended CO.sub.2-permeable and CO.sub.2-selective matrix that hosts the immobile or mobile CO.sub.2 carriers and porous nanostructures that adsorb water vapors. The CO.sub.2-philic layer can be disposed upstream of the CO.sub.2-permeance layer such that a flow of source gas to be separate enters the membrane from a feed side at which the CO.sub.2-philic layer is present and CO.sub.2 exits the membrane at a permeate side after passing through both the CO.sub.2-philic layer and the CO.sub.2-permeance layer.

Described in the present application are methods of producing silane-crosslinked polymer membranes at moderate temperatures using acid catalysts that, in certain embodiments, result in membranes with unexpectedly high permeabilities and selectivities. In certain embodiments, grafting and crosslinking of the silanes occur by immersing a preformed membrane in a solution comprising a silane and an acid catalyst. Alternatively, in certain embodiments, grafting of silanes to a polymer occurs in the presence of acid catalyst in solution and subsequent casting and drying produces crosslinked membranes. In certain embodiments, an acid catalyst is a weak acid catalyst. Also described in the present application are asymmetric crosslinked polymer membranes with porous layers. In certain embodiments, crosslinked cellulose acetate membranes have permeability up to an order of magnitude greater than the permeability of unmodified cellulose acetate membranes. The membranes have porous layers with a high porosity due to their processing in moderate conditions.

Described in the present application are methods of producing silane-crosslinked polymer membranes at moderate temperatures using acid catalysts that, in certain embodiments, result in membranes with unexpectedly high permeabilities and selectivities. In certain embodiments, grafting and crosslinking of the silanes occur by immersing a preformed membrane in a solution comprising a silane and an acid catalyst. Alternatively, in certain embodiments, grafting of silanes to a polymer occurs in the presence of acid catalyst in solution and subsequent casting and drying produces crosslinked membranes. In certain embodiments, an acid catalyst is a weak acid catalyst. Also described in the present application are asymmetric crosslinked polymer membranes with porous layers. In certain embodiments, crosslinked cellulose acetate membranes have permeability up to an order of magnitude greater than the permeability of unmodified cellulose acetate membranes. The membranes have porous layers with a high porosity due to their processing in moderate conditions.

A photothermal distillation membrane including a polydopamine (PDA) coated, polyvinylidene fluoride (PVDF) membrane is disclosed, as well as a process for synthesizing same. A photothermal aerogel membrane including a polydopamine (PDA)-containing bacterial nanocellulose (BNC) is also disclosed, as well as a process for synthesizing same.

The present invention relates to self-assembled nano structures comprising polyalkyleneimine (PAI) and a detergent solubilized transmembrane protein, such as an aquaporin protein.