A process is provided to separate a hydrocarbon stream comprising a mixture of light olefins and light paraffins, the process comprising sending the hydrocarbon stream through a pretreatment unit to remove impurities selected from the group consisting of sulfur compounds, arsine, phosphine, methyl acetylene, propadiene, and acetylene to produce a treated hydrocarbon stream; vaporizing the treated hydrocarbon stream to produce a gaseous treated hydrocarbon stream; adding liquid or vapor water to the gaseous treated hydrocarbon stream; then contacting the gaseous treated hydrocarbon stream to a membrane in a membrane system comprising one or more membrane units to produce a permeate stream comprising about 96 to 99.9 wt % light olefins and a retentate stream comprising light paraffins.

A process is provided to separate a hydrocarbon stream comprising a mixture of light olefins and light paraffins, the process comprising sending the hydrocarbon stream through a pretreatment unit to remove impurities selected from the group consisting of sulfur compounds, arsine, phosphine, methyl acetylene, propadiene, and acetylene to produce a treated hydrocarbon stream; vaporizing the treated hydrocarbon stream to produce a gaseous treated hydrocarbon stream; adding liquid or vapor water to the gaseous treated hydrocarbon stream; then contacting the gaseous treated hydrocarbon stream to a membrane in a membrane system comprising one or more membrane units to produce a permeate stream comprising about 96 to 99.9 wt % light olefins and a retentate stream comprising light paraffins.

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.

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.

Described herein is a graphene material based membrane that provides selective resistance for solutes or gas while providing water permeability. A selectively permeable membrane comprising graphene oxide, reduced graphene oxide, and also functionalized or crosslinked between the graphene, that provides enhanced salt separation from water or gas permeability resistance, methods for making such membranes, and methods of using the membranes for dehydrating or removing solutes from water are also described.

A method of deionizing saline water by contacting the saline water with a diffusion barrier to remove at least a portion of divalent ions to form deionized water, in order to desalinate the deionized water without scale formation, and a method of fabricating the diffusion barrier. Various embodiments of the diffusion barrier, the method of fabricating thereof, and the method of deionizing the saline water are provided.

The present invention provides, inter alia, compositions including at least one pliable layer comprising a plurality of silk fibroin nanofibrils, and at least one rigid layer comprising a plurality of mineral crystals, wherein each rigid layer is associated with at least one pliable layer, as well as methods for the production and use thereof.

Described herein is a graphene material and polymer-based anti-microbial element that provides anti-microbial capabilities. Described is an element that can also comprise a support. Also described is an element where the support can be the article to be protected from microbial buildup. Also described are methods for preventing microbial fouling by applying the aforementioned anti-microbial elements and related devices.

This invention relates thin film nanocomposites (TFNCs) and methods of preparing the same by molecular layer-by-layer assembly. The TFNCs comprise a porous nanofibrous support first layer coated with a mid-layer having an outer separating layer, wherein the out separating layer has one or more bilayers or trilayers. The TFNCs can be particularly suitable for use as filtration membranes for the separation of dissolved components from fluids such as ultrafiltration, nanofiltration, and reverse osmosis. Thus, embodiments of the invention also include filtration systems and methods of filtering.

The present invention relates to a polymeric hollow fiber membrane and a carbon molecular sieve hollow fiber membrane, both of which have excellent gas separation performance, and processes for preparing the same. Specifically, the present invention relates to a hybrid polymeric hollow fiber membrane that comprises a glassy polymer containing fluorine and a ladder-structured polysilsesquioxane, a hybrid carbon molecular sieve hollow fiber membrane prepared by pyrolysis thereof, and processes for preparing the same. The hybrid polymeric hollow fiber membrane and the hybrid carbon molecular sieve hollow fiber membrane according to the embodiments of the present invention are excellent in gas flux and selectivity and can have a large surface area per unit volume. Thus, they can be advantageously used for separating gases with a high energy efficiency on a large scale.