The present invention relates to a separator membrane having a hierarchical structure, a production method therefor and a xylene separation method using same, and to: a separator membrane having a hierarchical structure comprising mesopores, the separator membrane having mesopores introduced inside a microporous zeolite separator membrane, thereby being thin, having less defects and exhibiting high xylene permeation and separation performance; a production method therefor; and a xylene separation method using same.

A composite body comprising a porous layer (1) made from oxide particles connected to one another and partially to a substrate, containing at least one oxide of the elements Al, Zr, Ti or Si, and comprising a further porous layer (2) at least on one side, having oxide particles connected to one another and partially to the layer (1) and containing at least one oxide of the elements Al, Zr, Ti or Si, wherein the oxide particles in the layer (1) have a greater average particle size (d.sub.50 is 0.5 to 4 μm) than the oxide particles in the layer (2) (d.sub.50 is 0.015 to 0.15 μm), characterised in that a polymer coating (PB) is provided on or above the layer (2), containing one or more polysiloxanes. A method for producing corresponding composite bodies and to the use thereof.

The present invention relates to a method for recovering a rare metal salt, the method including: an acid treatment step of obtaining a rare metal-containing acidic aqueous solution by bringing a material including a monovalent rare metal and a polyvalent rare metal into contact with an acidic aqueous solution; a separation step of obtaining permeated water including the monovalent rare metal and non-permeated water including the polyvalent rare metal from the rare metal-containing acidic aqueous solution by using a nanofiltration membrane satisfying the condition (1); and a concentration step of obtaining non-permeated water having a higher concentration of the monovalent rare metal and permeated water having a lower concentration of the monovalent rare metal than that of the permeated water in the separation step, by using a reverse osmosis membrane.

The present application relates to the technical field of further processing of dairy products, and in particular to a preparation method of milk oligosaccharides, and milk oligosaccharide powder and food prepared thereby. The preparation method comprises the steps of: performing ultrafiltration of whey liquid for at least three times, subjecting the ultrafiltration permeate to nanofiltration concentration for several times, then subjecting the nanofiltration retentate to chromatographic separation and purification, collecting chromatographic collection liquid containing sialyllactose while removing the fraction containing lactose, subjecting the collection to desalination and drying to obtain oligosaccharide powder. The milk oligosaccharides prepared by the present method and the food product containing the same comprise basically bovine milk oligosaccharides, which are light yellow or white in color, light in flavor, uniform in size, and have good thermal stability and solubility. The milk oligosaccharides mainly comprise 3′-sialyllactose and 6′-sialyllactose.

A porous membrane laminate of the present disclosure includes a porous support layer and a porous membrane laminated on one surface of the support layer and containing polytetrafluoroethylene as a main component. The porous membrane is formed of a uniaxially stretched material, the porous membrane has a mean pore size of 25 nm to 35 nm and a maximum pore size of 49 nm or less, and the porous membrane has an average thickness of 0.6 μm to 3.5 μm.

A device and method for separating and recovering intestinal contents, comprising removing the impurities from the intestinal contents by means of coarse filtration and cross-flow fine filtration, followed by obtaining a concentrate by microporous membrane cross-flow filter, and collecting the target contents. The microporous membrane has a spongy porous structure, and can rapidly and effectively achieve the separation and recovery of flora from the intestinal contents by cooperation with cross-flow filtration. The separated and recovered dry flora comprises at least 10-20% of the initial wet intestinal contents, and comprises at least 10.sup.11/1 g dry flora.

One embodiment of the present invention provides a hydrophilic composite porous membrane including: a polyolefin microporous membrane, and an olefin/vinyl alcohol-based resin with which at least one main surface and inner surfaces of pores of the polyolefin microporous membrane are coated, in which a ratio t/x of a membrane thickness t (μm) to an average pore diameter x (μm), as measured with a perm porometer, is from 50 to 630.

The porous hollow fiber membrane of the present invention contains a thermoplastic resin, and includes a surface having a surface porosity of 32 to 60% and a fine pore diameter of 300 nm or less, and has a compressive strength of 0.7 MPa or more. The porous hollow fiber membrane of the present invention may include at least two layers, and in this case, the surface of one layer has a thickness of backbone of 0.3 to 20 μm and a fine pore diameter of 0.3 to 10 μm, and the surface of the other layer has a surface porosity of 32 to 60% and a fine pore diameter of 0.05 to 0.3 μm.

Embodiments of the present disclosure describe an isoporous polymer membrane comprising a polymeric film having a plurality of isopores, wherein the isoporous polymer membrane is characterized in that it has one or more of the following features: a porosity of about 20% or greater, a plurality of isopores arranged in an ordered array, wherein the plurality of isopores extend from a first membrane surface to a second membrane surface along an axis perpendicular to the first and second membrane surfaces, a membrane size of about 45 cm.sup.2 or greater, and a pore size of about 2 μm or less. Embodiments of the present disclosure also describe methods of fabricating the isoporous polymer membranes, applications using the isoporous polymer membranes, and the like.

The present invention provides a porous membrane for water treatment, comprising: a high molecular weight polyethylene, a water-soluble polymer and an antioxidant, the high molecular weight polyethylene having an average molecular weight of 1.0×10.sup.5 to 10.0×10.sup.6 and a density of 0.940 to 0.976 g/cm.sup.3; wherein, the weight of the water-soluble polymer is 5 to 50 parts, the weight of the antioxidant is 0.1 to 10 parts, based on 100 parts of the weight of the high molecular weight polyethylene. The porous membrane for water treatment prepared by the present invention has a thickness of 5 to 30 μm, a pore size of 10 to 100 nm, a porosity of 20 to 60%, and a surface contact angle of 30° to 95°. The porous membrane according to the present invention has good durability, simple preparation process, and relatively thin thickness, a uniform pore size distribution and small pore size, good hydrophilicity, as well as good filtration and adsorption effect.