Abstract: A fuel cell system and an operating method of the same. The fuel cell system includes a carbon monoxide adsorbing device that is disposed at an exit of a shift reactor and removes carbon monoxide which is not completely removed in the shift reactor. Therefore, a start-up time of the fuel cell system is remarkably reduced without poisoning catalysts of electrodes of the fuel cell. An overall volume of the fuel cell system can be reduced since the carbon monoxide adsorbing device is only operating during the start-up, and thus the fuel cell system can be economically manufactured and operated. Additionally, the carbon monoxide adsorbent can be regenerated, thereby increasing economic efficiency of the fuel cell system.

Abstract: The present invention relates to a method for the preparation of a high molecular weight polycarbonate resin, and more particularly to a method for preparing a high molecular weight polycarbonate resin using a solid state polymerization method after the preparation of a crystalline polycarbonate or-conducting the preparation of the crystalline polycarbonate and the solid state polymerization thereof simultaneously. According to the method for the preparation of a high molecular weight polycarbonate resin of the invention, it is possible to produce a high molecular weight polycarbonate resin having a narrow molecular weight distribution and uniform properties and that is applicable to injection and extrusion in large quantities with a low cost within a short time.

Abstract: The present invention relates to a process for preparing high molecular weight polycarbonate resin, particularly to a process for preparing high molecular weight polycarbonate resin, which conducts condensation polymerization of low molecular weight amorphous polycarbonate prepolymer prepared by transesterification of dialkyl(aryl)carbonate and aromatic hydroxy compound and solid state polymerization within short time to increase molecular weight. The present invention introduces condensation polymerization to lower mole fractions of arylcarbonate existing in unreacted diarylcarbonate, end groups of reaction by products of polymerization degree less than 3, and polycarbonate prepolymer obtained by transesterification, and thus can maximize molecular weight increase of polycarbonate after solid state polymerization and remarkably reduce time required for preparing polycarbonate of the same molecular weight.

Abstract: A zeolite adsorbent for desulfurization and a method of preparing the same. More particularly, a zeolite adsorbent for desulfurization in which the relative crystallinity of Y zeolite that is ion exchanged with Ag is 45% to 98%, and a method of preparing the same. The zeolite adsorbent for desulfurization has excellent crystallinity over the known zeolite adsorbent for desulfurization, and thus has better performance of adsorbing sulfur compounds though it contains less Ag. Accordingly, when the sulfur compounds of a fuel gas are removed by employing the zeolite adsorbent for desulfurization, a desulfurizing device that is bettereven with less cost can be constructed.

Abstract: The present invention relates to a method for the preparation of a high molecular weight polycarbonate resin, and more particularly to a method for preparing a high molecular weight polycarbonate resin using a solid state polymerization method after the preparation of a crystalline polycarbonate or-conducting the preparation of the crystalline polycarbonate and the solid state polymerization thereof simultaneously. According to the method for the preparation of a high molecular weight polycarbonate resin of the invention, it is possible to produce a high molecular weight polycarbonate resin having a narrow molecular weight distribution and uniform properties and that is applicable to injection and extrusion in large quantities with a low cost within a short time.

Abstract: A catalytic system for CO removal includes a gold (Au) catalyst and a co-catalyst in contact with an aqueous phase, and a fuel cell system using the same. The catalytic system is relatively very simple compared to a common CO removal system, and can highly efficiently remove CO at low temperature without side reaction. In addition, water contacted in the catalytic system can act as a buffer for the rise and fall of temperature, and thus, can cope with an accidental temperature change. Further, the catalytic system shows a low operation temperature, and thus, can be operated over a broad operation range considering the activity and/or selectivity of the gold catalyst, etc.

Abstract: The present invention relates to a method for preparing polycarbonate resin, and more particularly to a method for effectively preparing polycarbonate resin having a large molecular weight in a short time under a melt polymerization condition using a catalyst system comprising phosphoranylidene ammonium salts, which is stable and maintains superior reactivity during melt polymerization and solid state polymerization.

Abstract: The present invention relates to a process for preparing high molecular weight polycarbonate resin, particularly to a process for preparing high molecular weight polycarbonate resin, which conducts condensation polymerization of low molecular weight amorphous polycarbonate prepolymer prepared by transesterification of dialkyl(aryl)carbonate and aromatic hydroxy compound and solid state polymerization within short time to increase molecular weight. The present invention introduces condensation polymerization to lower mole fractions of arylcarbonate existing in unreacted diarylcarboante, end groups of reaction by products of polymerization degree less than 3, and polycarbonate prepolymer obtained by transesterification, and thus can maximize molecular weight increase of polycarbonate after solid state polymerization and remarkably reduce time required for preparing polycarbonate of the same molecular weight.