Abstract: Provided is a double crosslinked sodium alginate/polyvinyl alcohol composite nanofiltration membrane, including: a porous polymer support; and a sodium alginate/polyvinyl alcohol blend coating layer formed on the porous polymer support and having a first crosslinking structure formed by complexation with divalent metal ions and a second crosslinking structure formed by acetalization with aldehyde groups. The double crosslinked sodium alginate/polyvinyl alcohol composite nanofiltration membrane disclosed herein not only shows excellent chlorine resistance but also has improved water permeation flux and salt rejection ratio, and thus may be manufactured in the form of a spirally wound type membrane module and applied to a water treatment system in which it may be utilized for an actual nanofiltration separation process.

Abstract: A carbon dioxide conversion system is provided. The carbon dioxide conversion system includes: an ion transfer membrane that separates oxygen in the air; an oxy-fuel combustor that combusts using oxygen that is separated at the ion transfer membrane as an oxidizing agent; and a dry-reformer that converts carbon dioxide that is generated through an oxy-fuel combustion reaction of the oxy-fuel combustor and methane gas that is supplied from the outside to carbon monoxide and hydrogen by a dry-reforming reaction.

Abstract: Provided is a double crosslinked sodium alginate/polyvinyl alcohol composite nanofiltration membrane, including: a porous polymer support; and a sodium alginate/polyvinyl alcohol blend coating layer formed on the porous polymer support and having a first crosslinking structure formed by complexation with divalent metal ions and a second crosslinking structure formed by acetalization with aldehyde groups. The double crosslinked sodium alginate/polyvinyl alcohol composite nanofiltration membrane disclosed herein not only shows excellent chlorine resistance but also has improved water permeation flux and salt rejection ratio, and thus may be manufactured in the form of a spirally wound type membrane module and applied to a water treatment system in which it may be utilized for an actual nanofiltration separation process.

Abstract: Provided is a polyacrylonitrile/chitosan composite nanofiltration membrane, including: a polyacrylonitrile support; and a chitosan coating layer modified with graphene oxide, or a polyacrylonitrile/chitosan composite nanofiltration membrane, including: a polyacrylonitrile support modified with graphene oxide; and a chitosan coating layer or chitosan coating layer modified with graphene oxide. The polyacrylonitrile/chitosan composite nanofiltration membrane containing graphene oxide shows high permeability and a high salt rejection ratio, has excellent anti-fouling property and chlorine resistance, and thus may be manufactured in the form of a spirally wound type membrane module applied to a water treatment system so that it may be utilized for an actual nanofiltration separation process.

Abstract: Provided is a nanocomposite ultrafiltration membrane including a hydrophobic polymer matrix impregnated with graphene oxide or reduced graphene oxide. The PAN/GO nanocomposite ultrafiltration membrane has improved mechanical properties, high permeability and a high salt rejection ratio, and excellent anti-fouling property and durability. Thus, the nanocomposite ultrafiltration membrane may be manufactured in the form of a membrane module applied to a water treatment system so that it may be utilized in an actual ultrafiltration separation process.

Abstract: A carbon dioxide conversion system is provided. The carbon dioxide conversion system includes: an ion transfer membrane that separates oxygen in the air; an oxy-fuel combustor that combusts using oxygen that is separated at the ion transfer membrane as an oxidizing agent; and a dry-reformer that converts carbon dioxide that is generated through an oxy-fuel combustion reaction of the oxy-fuel combustor and methane gas that is supplied from the outside to carbon monoxide and hydrogen by a dry-reforming reaction.

Abstract: Disclosed are a nano-sized palladium-doped anion exchange resin catalyst or palladium-doped cation exchange resin catalyst, a preparation method thereof and a method of removing dissolved oxygen in water using the same. The palladium-doped anion exchange resin catalyst exhibits high dissolved oxygen removal efficiency of 99˜99.99%, and the palladium-doped cation exchange resin catalyst exhibits high dissolved oxygen removal efficiency of at least 97%, and further, dissolved oxygen in water can be removed through a catalytic reaction without the use of additional chemicals, thereby discharging no secondary pollutants. This catalyst is environmentally friendly, can be continuously developed, and can prevent the loss of the palladium catalyst, which is expensive, and thus can be efficiently applied to various fields, including semiconductors, power plants, microbial culture, food and pharmaceutical production, and the fermentation industry.

Abstract: The present invention relates to a titania composite membrane for separating water/alcohol mixtures and a method of preparation thereof, and more particularly to the titania composite membrane and the method of preparation thereof, wherein a surface of a porous support is modified with silica xerogel and ?-alumina sol and titania sol is coated on the modified surface to form a titania surface layer and then the obtained titania surface layer is dried and calcined to optimize performance of separation and promote thermal stability. The titania composite membrane of the present invention has excellent properties such as thermal stability, mechanical strength and good perm-selectivity for water molecule in water/alcohol mixtures due to the hydrophilic property of the titania surface layer, thus being applicable to the membrane for separating water/alcohol mixtures.

Abstract: Disclosed are a nano-sized palladium-doped anion exchange resin catalyst or palladium-doped cation exchange resin catalyst, a preparation method thereof and a method of removing dissolved oxygen in water using the same. The palladium-doped anion exchange resin catalyst exhibits high dissolved oxygen removal efficiency of 99˜99.99%, and the palladium-doped cation exchange resin catalyst exhibits high dissolved oxygen removal efficiency of at least 97%, and further, dissolved oxygen in water can be removed through a catalytic reaction without the use of additional chemicals, thereby discharging no secondary pollutants. This catalyst is environmentally friendly, can be continuously developed, and can prevent the loss of the palladium catalyst, which is expensive, and thus can be efficiently applied to various fields, including semiconductors, power plants, microbial culture, food and pharmaceutical production, and the fermentation industry.

Abstract: The present invention relates to a method for preparing a metallic membrane, more particularly to a method for preparing metallic membranes, which comprises dissolving a transition metal of Period 3 and its alloy particle powder and synthetic polymer in a fixed ratio; radiating or casting to prepare a membrane precursor; oxidizing the synthetic polymer on the membrane precursor under a mixed gaseous atmosphere of nitrogen and hydrogen; and sintering the membrane precursor at a predetermined temperature. The metallic membrane prepared by the process of the present invention has excellent mechanical and chemical properties and enables to maintain a relatively small pore size and high porocity than traditional membranes. Therefore, it is useful for water treatment.

Abstract: The present invention relates to a titania composite membrane for separating water/alcohol mixtures and a method of preparation thereof, and more particularly to the titania composite membrane and the method of preparation thereof, wherein a surface of a porous support is modified with silica xerogel and ?-alumina sol and titania sol is coated on the modified surface to form a titania surface layer and then the obtained titania surface layer is dried and calcined to optimize performance of separation and promote thermal stability. The titania composite membrane of the present invention has excellent properties such as thermal stability, mechanical strength and good perm-selectivity for water molecule in water/alcohol mixtures due to the hydrophilic property of the titania surface layer, thus being applicable to the membrane for separating water/alcohol mixtures.

Abstract: The present invention relates to a method for preparing a metallic membrane, more particularly to a method for preparing metallic membranes, which comprises dissolving a transition metal of Period 3 and its alloy particle powder and synthetic polymer in a fixed ratio; radiating or casting to prepare a membrane precursor; oxidizing the synthetic polymer on the membrane precursor under a mixed gaseous atmosphere of nitrogen and hydrogen; and sintering the membrane precursor at a predetermined temperature. The metallic membrane prepared by the process of the present invention has excellent mechanical and chemical properties and enables to maintain a relatively small pore size and high porocity than traditional membranes. Therefore, it is useful for water treatment.

Abstract: The present invention relates to a process for preparing dimethyl ether from methanol. More particularly, this invention relates to an improved process for preparing dimethyl ether with high yield useful as a clean fuel as well as a raw material in chemical industry performed via a catalytic system, wherein dehydration of methanol is first carried out by using a hydrophilic solid acid catalyst and then subsequent dehydration of methanol is carried out continuously by using a hydrophobic zeolite solid acid catalyst in the concurrent presence of unreacted methanol, dimethyl ether produced and water.

Abstract: The present invention relates to a method for preparing a composite silica membrane with thermal stability by a soaking-rolling method, and more particularly to a method for preparing a composite silica membrane with improved thermal stability by rolling the surface of a porous support with silica xerogel, soaking-rolling the surface with ?-alumina, coating, drying, and sintering the porous support surface, thereby forming a fine coating membrane on the porous support surface.

Abstract: The present invention relates to a silicone-coated organic solvent resistant polyamide composite nanofiltration membrane and a method for preparing the same. More particularly, the present invention relates to a nanofiltration composite membrane that is not only rejection rate superior but also organic solvent stable and flux excellent, prepared by coating with silicone during the process of interfacial polymerization of polyamide on the surface of porous support; and a method for producing it.

Abstract: The present invention relates to a method for preparing dimethylether from methanol using a membrane reactor, more particularly to a method for preparing dimethylether from methanol using a membrane capable of carrying out a reaction and a separation at the same time while preparing dimethylether from methanol. Because water vapor generated by dehydration of methanol can be selectively removed from the catalytic reaction zone, decrease in catalytic activity can be prevented and thus life span of a catalyst can be extended. Further, reaction efficiency can be improved even at a temperature milder than the conventional one for dimethylether preparation, and also additional steps of separation and purification after completion of the reaction is no longer necessary.

Abstract: The present invention relates to a process for preparing dimethyl ether from crude methanol.

Abstract: The present invention relates to a method for preparing a composite silica membrane with thermal stability by a soaking-rolling method, and more particularly to a method for preparing a composite silica membrane with improved thermal stability by rolling the surface of a porous support with silica xerogel, soaking-rolling the surface with &ggr;-alumina, coating, drying, and sintering the porous support surface, thereby forming a fine coating membrane on the porous support surface.

Abstract: The present invention relates to a method for preparing dimethylether from methanol using a membrane reactor, more particularly to a method for preparing dimethylether from methanol using a membrane capable of carrying out a reaction and a separation at the same time while preparing dimethylether from methanol. Because water vapor generated by dehydration of methanol can be selectively removed from the catalytic reaction zone, decrease in catalytic activity can be prevented and thus life span of a catalyst can be extended. Further, reaction efficiency can be improved even at a temperature milder than the conventional one for dimethylether preparation, and also additional steps of separation and purification after completion of the reaction is no longer necessary.

Abstract: The present invention relates to a silicone-coated organic solvent resistant polyamide composite nanofiltration membrane and a method for preparing the same. More particularly, the present invention relates to a nanofiltration composite membrane that is not only rejection rate superior but also organic solvent stable and flux excellent, prepared by coating with silicone during the process of interfacial polymerization of polyamide on the surface of porous support; and a method for producing it.