Abstract: The present invention provides an oxygen selective adsorbent containing oxides of BaxSr(1?x)Mgy(CO3)(1+y) or BaxSr(1?x)CO3 particles, increasing transition oxygen partial pressure, and representing high thermal stability and excellent oxygen sorption cavity, by adding another metal such as Sr to Ba which is active element for oxygen adsorption, so as to be capable of desorbing oxygen under lower vacuum even at the same operating temperature than the existing oxygen selective adsorbent; and a preparation method thereof.

Abstract: The present invention provides an oxygen selective adsorbent containing oxides of BaxSr(1?x)Mgy(CO3)(1+y) or BaxSr(1?x)CO3 particles, increasing transition oxygen partial pressure, and representing high thermal stability and excellent oxygen sorption cavity, by adding another metal such as Sr to Ba which is active element for oxygen adsorption, so as to be capable of desorbing oxygen under lower vacuum even at the same operating temperature than the existing oxygen selective adsorbent; and a preparation method thereof.

Abstract: Provided is a system for liquefying natural gas including: a pre-cooling means; a gas-liquid separating means; a first heat exchanging means; a second heat exchanging means; a first expanding means; a second expanding means; a first mixed refrigerant converting means; a pre-cooled refrigerant supplying means; a natural gas supplying means; and a mixer. Provided is also a method for liquefying natural gas including: a first pre-cooling operation (S01); a first mixed refrigerant separating operation (S02); a first introducing operation (S03); a first expanded refrigerant forming operation (S04); a second introducing operation (S05); a second expanded refrigerant forming operation (S06); and a second cooling operation (S07).

Abstract: Provided are a continuous oxygen adsorption and desorption device and an continuous oxygen adsorption and desorption method using the device, and more particularly, an continuous oxygen adsorption and desorption device for producing high-purity oxygen products by using a plurality of adsorption and desorption towers filled with an oxygen-selecting adsorption and desorption agent selected from BaMg(CO3)2 particles or particles in which either MgCO3 or Mg(OH)2 has been attached to the outside of BaMg(CO3)2, and also a continuous oxygen adsorption and desorption method using the device.

Abstract: Provided are a continuous oxygen adsorption and desorption device and an continuous oxygen adsorption and desorption method using the device, and more particularly, an continuous oxygen adsorption and desorption device for producing high-purity oxygen products by using a plurality of adsorption and desorption towers filled with an oxygen-selecting adsorption and desorption agent selected from BaMg(CO3)2 particles or particles in which either MgCO3 or Mg(OH)2 has been attached to the outside of BaMg(CO3)2, and also a continuous oxygen adsorption and desorption method using the device.

Abstract: The present invention provides an oxygen selective adsorbent containing BaxSr(1?x)Mgy(CO3)(1+y) or BaxSr(1?x)CO3 particles, increasing transition oxygen partial pressure, and representing high thermal stability and excellent oxygen sorption cavity, by adding another metal such as Sr to Ba which is active element for oxygen adsorption, so as to be capable of desorbing oxygen under lower vacuum even at the same operating temperature as existing oxygen selective adsorbents, and a preparation method thereof.

Abstract: Disclosed is a process for effecting liquid-phase hydrogenation of MAN to GBL in high conversion and high selectivity. The present invention provides an improved process of catalytic hydrogenation for converting MAN or SA to GBL in the liquid phase in the presence of a noble metal (palladium-molybdenum-nickel) catalyst supported on silica having a large surface area. The catalytic hydrogenation is conducted at a temperature of 150 to 250° C. and under a pressure of 50 to 150 kg/cm2.

Abstract: Disclosed is a process for effecting liquid-phase hydrogenation of MAN to GBL in high conversion and high selectivity. The present invention provides an improved process of catalytic hydrogenation for converting MAN or SA to GBL in the liquid phase in the presence of a noble metal (palladium-molybdenum-nickel) catalyst supported on silica having a large surface area. The catalytic hydrogenation is conducted at a temperature of 150 to 250° C. and under a pressure of 50 to 150 kg/cm2.