Abstract:
This invention relates to a bismuth molybdate catalyst, a preparation method thereof, and a method of preparing 1,3-butadiene using the same, and to a bismuth molybdate catalyst, a preparation method thereof, and a method of preparing 1,3-butadiene using the same, in which 1,3-butadiene can be prepared through oxidative dehydrogenation directly using a C4 mixture including n-butene and n-butane as a reactant in the presence of a mixed-phase bismuth molybdate catalyst including α-bismuth molybdate (Bi2Mo3On) and γ-bismuth molybdate (Bi2MoO6). According to this invention, the C4 raffinate, containing many impurities, is used as a reactant, without an additional n-butane separation process, thus obtaining 1,3-butadiene at high yield. Unlike complicated multicomponent-based metal oxides, the catalyst of the invention has simple constituents and synthesis routes, and can be easily formed through physical mixing, and thus is very advantageous in assuring reproducibility and can be directly applied to commercial processes.
Abstract:
This invention relates to a method of preparing multicomponent bismuth molybdate catalysts composed of four metal components and a method of preparing 1,3-butadiene using the catalyst, and particularly, to multicomponent bismuth molybdate catalysts composed of a divalent cationic metal, a trivalent cationic metal, bismuth and molybdenum, a preparation method thereof, and a method of preparing 1,3-butadiene from a C4 mixture including n-butene and n-butane using oxidative dehydrogenation. According to this invention, it is possible to prepare catalysts having high activity for the preparation process of 1,3-butadiene only using four metal components as shown through systematic investigation of types and ratios of metal components, unlike conventional multicomponent metal oxide catalysts having a complicated composition of metal components.
Abstract:
A display device may include a first substrate, a second substrate, and a liquid crystal layer. The first substrate may include a domain-forming layer including a depression pattern for forming a liquid crystal domain in a pixel area and a pixel electrode formed on the domain-forming layer. The second substrate may face the first substrate. The second substrate may include a common electrode formed on the entire surface thereof. The liquid crystal layer may be disposed between the first substrate and the second substrate. The liquid crystal layer may include a reactive mesogen (RM) which fixes liquid crystal molecules formed in the liquid crystal domain. Since a liquid crystal domain may be formed without a separate pattern on a common electrode, a display device having an enhanced aperture ratio and an enhanced viewing angle may be manufactured.
Abstract:
Disclosed herein is a method of producing an optically active thiophene-based compound using a simulated moving bed adsorption separation process, and more specifically, a method of continuously separating a racemic thiophene-based compound into its optically active thiophene-based compounds having high purity, through optical resolution using the simulated moving bed process. According to the method of the current invention, a racemic mixture of a thiophene-based compound can be continuously separated into its optically active thiophene-based compounds having high purity, which is an intermediate of optically active dorzolamide acting as a topical therapeutic agent for glaucoma, using a simulated moving bed adsorption separation technique, thereby increasing industrial usability.
Abstract:
A liquid crystal display includes a first substrate and a second substrate facing the first substrate, a gate line and a data line disposed on the first substrate, and a pixel electrode disposed on the first substrate. The pixel electrode is connected to the gate line and the data line, and includes subregions. The liquid crystal display further includes a storage electrode disposed on the first substrate overlapping the pixel electrode to form a storage capacitor, a common electrode disposed on the second substrate, and a liquid crystal layer interposed between the pixel electrode and the common electrode and including liquid crystal molecules disposed therein. The pixel electrode includes a stem defining boundaries between the subregions, and a width of the stem changes from a center portion of the pixel electrode to a peripheral portion of the pixel electrode.
Abstract:
This invention relates to a method of preparing a multicomponent bismuth molybdate catalyst by changing the pH of a coprecipitation solution upon coprecipitation and a method of preparing 1,3-butadiene using the catalyst. The multicomponent bismuth molybdate catalyst, coprecipitated using a solution having an adjusted pH, the preparation method thereof, and the method of preparing 1,3-butadiene through oxidative dehydrogenation using a C4 mixture including n-butene and n-butane as a reactant are provided. The C4 raffinate, containing many impurities, is directly used as a reactant without an additional process for separating n-butane or extracting n-butene, thus obtaining 1,3-butadiene at high yield. The activity of the multicomponent bismuth molybdate catalyst can be simply increased through precise pH adjustment upon coprecipitation, which is not disclosed in the conventional techniques. This method can be applied to the increase in the activity of multicomponent bismuth molybdate catalysts reported in the art.
Abstract:
The present invention relates to a hybrid process comprising an adsorption process and a distillation process for the separation of butene-1 from a C4 hydrocarbon mixture gas including butene-1, trans-2-butene, cis-2-butene, normal butane, isobutane, etc. The above hybrid process comprises introducing a gaseous C4 mixture into the adsorption tower loaded with adsorbents which adsorb olefins selectively to discharge C4 paraffins to the outlet of the tower, desorbing C4 olefins selectively adsorbed in the adsorption tower to produce high purity C4 olefins mixture gas in which isobutane and normal butane was removed, and separating the high C4 olefins mixture gas (a mixture of butene-1, trans-2-butene, cis-2-butene, and a trace amount of C4 paraffins) via distillation to obtain high purity butene-1 including a trace amount of isobutane in the top of the distillation tower and obtain a mixture gas including trans-2-butene, cis-2-butene and a trace amount of normal butane in the bottom of the tower.
Abstract:
A liquid crystal display (“LCD”) includes: a first substrate; a sensor pad disposed on the first substrate; a second substrate which faces the first substrate; a sensor spacer and a supporting spacer disposed on the second substrate; and a supporting dielectric portion disposed between the supporting spacer and the first substrate. The sensor spacer is spaced apart from the sensor pad, and includes a sensor electrode disposed on a portion of the sensor spacer which faces the sensor pad. The supporting spacer is spaced apart from the first substrate, and the supporting dielectric portion uniformly maintains a cell gap between the first substrate and the second substrate.
Abstract:
A frequency multiplier increases the frequency of an external clock and outputs a high-frequency external clock. A period determinator determines whether or not a predetermined period of the external clock elapses and outputs a period determination signal. A frequency selector selectively transmits the external clock or the high-frequency external clock to a clock input buffer under the control of a power-up signal and the period determination signal.