摘要:
Provided is an ion exchange membrane including an ionic vinyl alcohol polymer having a cation exchange group or an anion exchange group. The ion exchange membrane 1 includes a porous support 3 and the ionic vinyl alcohol polymer. The porous support is provided, in a thickness direction from one surface thereof, with an impregnated layer 2 at least a part of which is impregnated with the ionic vinyl alcohol polymer. The ionic vinyl alcohol polymer includes an ionic vinyl alcohol polymer having an ion exchange group selected from a cation exchange group or an anion exchange group. The ion exchange membrane has a zeta potential value (ζ1) at one surface and a zeta potential value (ζ2) at the other surface, which are represented by the formula (1). ζ 1 - ζ 2 / ζ 1 0.5 ζ 1 ≥ ζ 2
摘要:
There is provided a charge-mosaic membrane comprising a cationic block copolymer (P) having a vinyl alcohol polymer block (A) and a cationic-group containing polymer block (B) as components; and an anionic block copolymer (Q) having a vinyl alcohol polymer block (C) and an anionic-group containing polymer block (D) as components. Such a charge-mosaic membrane is useful as a charge-mosaic membrane for piezodialysis because it exhibits higher membrane strength and higher permselectivity and has a larger charge density and a larger salt permeation flux.
摘要:
Provided is a cation exchange membrane having a stable ion exchange performance during usage, being excellent in basic properties such as membrane resistance and ion transportation as well as strength, and useful for electrodialysis and a method for producing the same. The cation exchange membrane is composed of a polyvinyl alcohol copolymer including an anionic group-containing anionic polymer segment and a vinyl alcohol polymer segment, and having a microphase separation structure having a domain size (X) in a range from 0 nm
摘要:
There is provided a multilayered charge-mosaic membrane having a porous supporting layer (A), a porous intermediate layer (B) and a charge-mosaic layer (C), wherein the porous supporting layer (A), the porous intermediate layer (B) and the charge-mosaic layer (C) are located in this order; the porous supporting layer (A) and/or the porous intermediate layer (B) are made of a fiber layer containing hydrophilic fibers; a thickness of the porous intermediate layer (B) is 0.1 to 100 µm; a porosity of the porous supporting layer (A) is larger than a porosity of the porous intermediate layer (B); the cationic and/or the anionic polymers constituting the charge-mosaic layer (C) is a polyvinyl alcohol having an ionic group. Thus, there is provided a multilayered charge-mosaic membrane having a large salt permeation flux and excellent mechanical strength.
摘要:
There is provided an ion-exchange membrane comprising an ion-exchange layer made of a cationic polymer and/or an anionic polymer and a supporting layer, wherein the ion-exchange layer is formed on the supporting layer by printing. Such an ion-exchange membrane exhibits excellent anti-organic fouling and low membrane resistance, thereby high efficient and long-time stable electrodialysis can be achieved. Formation of the ion-exchange layer as a charge-mosaic layer consisting of the cationic polymer domains and the anionic polymer domains provides a charge-mosaic membrane exhibiting excellent electrolyte permselectivity and mechanical strength.
摘要:
A problem to be solved by the present invention is to provide an ion exchange membrane that can increase the surface area of a membrane effective for ion permeation, properly decreases the electric resistance of a flow passage between membranes and the attachment of a contaminating substance thereto, also enhances the mechanical strength of the membrane itself, and further, is less deformed or damaged due to swelling over a wide range of salt concentrations and even if there is a large difference in salt concentration between two solutions contacted with the membrane. The present invention provides an ion exchange membrane having a concavo-convex shape, wherein the ion exchange membrane has a flat portion in the vicinity of ends, and a convex curve and a concave curve resulting from curvatures of the ion exchange membrane itself form a convex part and a concave parts, respectively, in the concavo-convex shape of the ion exchange membrane, wherein the convex part extends linearly or curvedly, the concave part between the convex parts is flat, the concave part includes a first concave part adjacent to the convex part in the lateral direction of the convex part, along the longitudinal direction of the convex part, the convex part has an apex and a side face in the longitudinal direction, and the side face is inclined from the apex toward the first concave part.
摘要:
Provided is a method in which carbon dioxide can be efficiently fixed, calcium carbonate that is a valuable can be efficiently produced from carbon dioxide, and a waste gypsum board can be effectively recycled without being wasted as it is by using the waste gypsum board for fixing carbon dioxide. This method includes: a first step of bringing a first solution containing an alkali metal hydroxide and gas containing carbon dioxide into contact with each other to produce a second solution containing an alkali metal salt; and a second step of bringing the second solution and a gypsum-containing material into contact with each other to produce calcium carbonate.
摘要:
Provided is a calcium carbonate generation method and system in which calcium carbonate having a high purity can be generated using a calcium-containing waste. Provided is a calcium carbonate generation method of generating calcium carbonate from a calcium-containing waste, the calcium carbonate generation method including: a calcium dissolution step of adding aqueous hydrochloric acid to a calcium-containing waste and dissolving calcium to generate an aqueous solution containing a calcium ion; a separation step of adjusting a hydrogen ion concentration index of the aqueous solution containing a calcium ion and separating a component containing at least one selected from the group consisting of Si, Al, Mg, and heavy metal from the aqueous solution; and a calcium carbonate collection step of generating calcium carbonate using an aqueous solution obtained in the separation step and an aqueous solution containing potassium carbonate and/or sodium carbonate.
摘要:
This invention provides a novel graft polymer that has excellent proton conductivity, is capable of regulating hydrogen permeability, methanol permeability, and the like, and can serve as a starting material for a polymer electrolyte membrane, which facilitates moisture balance control and efficient operation of a fuel cell. A polymer electrolyte membrane composed of such graft polymer is also provided. This graft polymer comprises a main chain comprising a hydroxyl group-containing polymer and a graft chain comprising a polymer containing a sulfonic acid group-containing monomer.