An asymmetric polyvinylidene chloride copolymer membrane is made by a method using a dope solution comprised of a polyvinylidene chloride copolymer and a solvent that solubilizes the polyvinylidene chloride copolymer that is shaped to form an initial shaped membrane. The initial shaped membrane is then quenched in a liquid comprised of a solvent that is miscible with the solvent that solubilizes the polyvinylidene chloride copolymer but is immiscible with the polyvinylidene chloride copolymer to form a wet asymmetric polyvinylidene chloride copolymer membrane. The solvents are removed from the wet membrane to form the asymmetric polyvinylidene chloride (PVDC) copolymer membrane. The membrane then may be further heated to form a carbon asymmetric membrane in which the porous support structure and separation layer of the PVDC membrane is maintained. The asymmetric carbon membrane may be useful to separate gases such as olefins from their corresponding paraffins, hydrogen from syngas or cracked gas, natural gas or refinery gas, oxygen/nitrogen, or carbon dioxide and methane.

An object is to form a hole having a desired size accurately and uniformly in a carbon nanomaterial used for a filter or the like, such as a graphene, a carbon nanotube, or a carbon nanohorn.

Provided is a method for perforating a carbon nanomaterial for forming a hole having a desired size in a carbon nanomaterial, characterized in that the carbon nanomaterial is heated and held at a low temperature in the air containing oxygen of 160 to 250 C. for a predetermined time and that a hole having a desired size is thereby formed uniformly in the carbon nanomaterial by controlling a length of heating time.

Membranes having a permselective active layer of a copolymerized perfluorinated monomer and an non-fluorinated alkylvinylester monomer demonstrate superior selective permeability performance for separating gas mixtures compared to membranes of exclusively perfluorinated polymers. Preferred active layer compositions are copolymers of perfluoro-2,2-dimethyl-1,3 dioxole (PDD) copolymerized with an alkylvinyl ester such as vinyl acetate, and vinyl pivalate, and with alkylvinyl esters that are substantially hydrolyzed to provide copolymerized vinyl alcohol functionality. The membranes can have a thin, high diffusion rate, gutter layer of a fluorinated polymer highly permeable to nitrogen positioned between the active layer and a porous support layer. A novel copolymer effective in selectively permeable membranes is a copolymer of PDD and an alkylvinyl ester compound having the formula H.sub.2CCHOC(O)R.sup.1 in which R.sup.1 is a linear or branched alkyl group of from 2 to 5 carbon atoms.

A method for producing an asymmetric porous membrane includes: forming a first casting film from a casting solution on a carrier, the casting solution containing a hydrophobic polymer, a hydrophilic polymer, a water-soluble polymer, and a solvent; placing the first casting film in an environment containing water vapor to contact the first casting layer with the water vapor, thereby obtaining a second casting film, the environment having a temperature ranging from 20 C. to 33 C. and a relative humidity of 30% to 80%; and contacting the second casting film with a coagulating agent so as to perform a wet-phase inversion. The hydrophilic polymer is polyvinylpyrrolidone, polyalkylene glycol, or a combination thereof. The water-soluble polymer is a copolymer of vinylpyrrolidone and vinyl acetate, a copolymer of vinylpyrrolidone and alkylene glycol, a vinyl alcohol-based polymer, an ethylene glycol/propylene glycol based copolymer, an ethyleneimine-based polymer, a water-soluble cellulose, or combinations thereof.

Disclosed are a polyolefin resin composition usable in manufacturing a single-layered dry porous membrane having excellent meltdown and shutdown properties, and a porous membrane using the polyolefin resin composition. The present invention provides a polyolefin resin composition for a porous membrane, wherein the polyolefin resin composition includes 30 wt % to 70 wt % of a high-density polyethylene having a melt flow index (190 C., 2.16 kg load) of 0.1 g/10 min to 5 g/10 min, a crystallization temperature of 115 C. to 125 C., and a degree of crystallinity of 75% or greater, and 30 wt % to 70 wt % of a high-crystallinity polypropylene having a melt flow index (230 C., 2.16 kg load) of 5 g/10 min to 20 g/10 min.

M(SiF.sub.6)(pyz).sub.3 (M=Cu, Zn, Co, or Ni) has a pore size between a size of H.sub.2 and a size of CO.sub.2, and thus exhibits prominent screening performance for H.sub.2/CO.sub.2. A strong interaction between Cu(SiF.sub.6)(bpy).sub.2 and a CO.sub.2 molecule can hinder the transport of the CO.sub.2 molecule. The above two MOFs both can achieve the H.sub.2/CO.sub.2 separation. By preparing a dense MSiF.sub.6/polymer layer, MSiF.sub.6 is uniformly dispersed in the polymer and is fixed, and subsequently, MSiF.sub.6 is converted into M(SiF.sub.6)(pyz).sub.3 or Cu(SiF.sub.6)(bpy).sub.2 by interacting with an organic ligand. Through vapor-induced in-situ conversion, MOF particles can be well dispersed without interface defects between the MOF particles and the polymer. Even at a doping amount of 80%, the mechanical flexibility and stability of the MMM can still be retained.

Design, fabrication, and usage of a reactor are presented for synthesis of structured materials from a liquid-phase precursor by heating. The structured materials are particles, membranes or films of micro-porous molecular sieve crystals such as zeolite and meso-porous materials. The precursor solution and structured materials in the reactor are uniformly heated by a planar heater with characteristic heat transfer dimension in the range of 3 mm to 10 cm. A planar heater having width and length at least three times of the characteristic heat transfer dimension provides at least one surface of uniform temperature distribution for heating purposes. Heating is conducted over a temperature range of 20 to 300 C. The planar heater can be heated by electrical power of by thermal fluid.

One or more polymeric hollow fiber membranes are pyrolyzed to form one or more hollow fiber CMS membranes by directing a flow of pyrolysis gas through a polymeric membrane cartridge (including a porous center tube around which one or more green, polymeric, hollow fiber membranes is arranged) or a bundle of polymeric membranes (including a plurality of green, polymeric hollow fiber membranes oriented so that their ends are disposed with ends of the bundle) in a direction perpendicular to a length direction of the cartridge or bundle in order to sweep away off-gases that are formed during pyrolysis.

The present invention relates to a method for the production of a porous ceramic body, the method comprises the following steps: (i) selecting a ceramic powder; (ii) selecting a binder comprising a pre-ceramic polymer; (iii) mixing the ceramic powder from step (i) with the binder from step (ii) providing a ceramic composition; (iv) coating a porous support with the ceramic composition providing a ceramic coated porous support; (v) heating the ceramic coated porous support to a temperature between 500 C.-1500 C. producing the porous ceramic body.

One or more polymeric hollow fiber membranes are pyrolyzed to form one or more hollow fiber CMS membranes by directing a flow of pyrolysis gas through a bundle of polymeric membranes (including a plurality of green, polymeric hollow fiber membranes oriented so that their ends are disposed with ends of the bundle) in a direction perpendicular to a length direction of the bundle in order to sweep away off-gases that are formed during pyrolysis.