A two-reactor catalytic system including a catalytic membrane gasification reactor and a catalytic membrane water gas shift reactor. The catalytic system, for converting biomass to hydrogen gas, features a novel gasification reactor containing both hollow fiber membranes that selectively allow O.sub.2 to permeate therethrough and a catalyst that facilitates tar reformation. Also disclosed is a process of converting biomass to H2. The process includes the steps of, among others, introducing air into a hollow fiber membrane; mixing the O.sub.2 permeating through the hollow fiber membrane and steam to react with biomass to produce syngas and tar; and reforming the tar in the presence of a catalyst to produce more syngas.

A filter for isolating nucleic acid from a sample and methods of isolating and purifying nucleic acid from a sample are described. The filter has a first porous region and a second porous region. The first porous region is arranged to be contacted in use by the sample before the second porous region, and the first porous region has a nominal pore size that is greater than the second porous region.

Provided are a composite semipermeable membrane that will maintain a sufficient level of rejection performance even when produced using different thicknesses of a porous support or different production conditions, a separation membrane element having such a composite semipermeable membrane, and a method for producing such a composite semipermeable membrane. The composite semipermeable membrane includes a porous support including a nonwoven fabric layer and a polymer porous layer on one surface of the nonwoven fabric layer; and a separation function layer on the surface of the porous support, wherein the porous support has a defect frequency F1 of 50 or less per 480 m.sup.2 with respect to defects having a width of 0.3 mm or more perpendicular to the direction of the polymer porous layer production line, when the relationship between the size and frequency of defects in the porous support is measured with transmitted light.

A polyolefin microporous membrane is disclosed. The membrane has a width of not less than 100 mm, and a variation range of an F25 value in a width direction is not greater than 1 MPa. The F25 value is a value obtained by dividing a load at 25% elongation of a sample of the laminated polyolefin microporous membrane as measured with a tensile testing machine by a cross-sectional area of the sample.

A hand-carry gravity-driven water filter with high throughput and water disinfection performance is formed. Membranes used for this water filter can be fabricated using electrospun method and non-solvent induced phase inversion method. A novel composite membrane structure (interwoven composite structure) was designed for further enhances water permeability and mechanical strength. The composite membrane can be composed of nanofibers with different diameter from the same polymer or different polymers. Membrane porosity and surface pore size can be controlled. Silver nanoparticles can be in-situ loaded on the surface of the membranes. The developed filter is effective for removal of a wide range of contaminants (e.g., pathogens, suspended solids and heavy metals). The purification process can be carried out under the drive of gravity (with an option for mechanically-enhanced filtration) without electricity.

A method for producing a fluorosulfonyl group-containing compound to obtain a compound represented by the following formula 5 from a compound represented by the following formula 1 as a starting material and a method for producing a fluorosulfonyl group-containing monomer in which the fluorosulfonyl group-containing compound is used: ##STR00001##
wherein R.sup.1 and R.sup.2 are a C.sub.1-3 alkylene group, and R.sup.F1 and R.sup.F2 are a C.sub.1-3 perfluoroalkylene group.

A hydrophobic-oleophilic and hollow fiber composite membrane includes hollow tubular braids and surface separation layers coated on the outer surfaces of the hollow tubular braids. Membrane-forming polymers in the surface separation layers are polyvinylidene fluoride, and all other components are hydrophobic ingredients, including graphene. A preparing method includes preparing hollow tubular braids by two-dimensional braided technique using polyester filaments, wherein the hollow tubular braids are used as the reinforcements. The method further includes mixing polyvinylidene fluoride, hydrophobic pore-forming agent, and the rest of solvent to prepare a casting solution of surface separation layer. The method further includes pre-treatment processing of the reinforcements; and coating the casting solution of surface separation layer on the outer surface of the processed reinforcements through a spinning spinneret to form a primary membrane. The reinforcements are replaced by the primary after post-processing, and repeating the coating process.

Provided are reverse-osmosis-membrane device capable of treating raw water including a large amount of membrane foulants, such as MBR-treated water, with stability while preventing a reduction in the amount of permeate, and a method for operating the reverse-osmosis-membrane device. The raw water includes a high-molecular organic substance having a molecular weight of 10,000 or more at a concentration of 0.01 ppm or more. The reverse-osmosis-membrane device includes a reverse-osmosis-membrane element including a membrane unit, the membrane unit including a reverse osmosis membrane having a thickness of 0.1 mm or less, a feed spacer disposed on a surface of the reverse osmosis membrane, and a permeate spacer disposed on the other surface of the reverse osmosis membrane. The reverse-osmosis-membrane device is operated at a permeation flux of 0.6 m/d or less.

Described herein are crosslinked polymeric based composite membranes that provide selective resistance for gases while providing water vapor permeability. Such composite membranes have a high water/air selectivity in permeability. The methods for making such membranes and using the membranes for dehydrating or removing water vapor from gases are also described.

A membrane for the purification of blood, or a dialysis membrane, in hollow-fiber membrane or flat membrane geometry, made of a composite assembled from at least a base membrane based on at least one polysulfone or a polyphenylsulfone with at least one pore-forming hydrophilic additive and at least one functional layer arranged on the base membrane, whereby the functional layer is formed from at least one polymeric polycationic bonding agent and at least one polymeric polyanion, whereby the base membrane is made of a material which is selected from: a polysulfone [PSU], a sulfonated polysulfone [SPSU], a polyethersulfone [PES], a sulfonated polyethersulfone [SPES], a polyphenylsulfone [PPSU], a sulfonated polyphenylsulfone [SPPSU]; and mixtures of these.