9 results about "Temperature-programmed reduction" patented technology

The application discloses a preparation method of a supported high-dispersion molybdenum phosphide catalyst, and comprises the following steps: S1, dissolving molybdenum acetylacetonate and ammonium hypophosphite in an aqueous solution of N,N-dimethylformamide to obtain an impregnation solution; S2, immersing a carrier in the impregnation solution, then drying and reducing to obtain a supported molybdenum phosphide catalyst. The hydrogenation activity and the hydrodesulfurization activity of the prepared molybdenum phosphide catalyst are higher than those of MoP catalysts prepared by a temperature programmed reduction method and a molybdenum trioxide reduction method with ammonium hypophosphite, and the molybdenum phosphide catalyst has very high hydrodesulfurization activity on p-benzothiophene.

The invention relates to a preparation method of metal beryllium based on a composite reducing agent. The preparation method comprises the following steps: 1) preparing an aluminum oxide coated magnesium composite reducing agent by adopting an in-situ chemical precipitation method; the preparation method comprises the following steps of (1) preparing a composite reducing agent, (2) mixing: mixing the composite reducing agent obtained in the step (1) with beryllium fluoride powder, (3) carrying out temperature programming reduction: carrying out two-stage temperature programming reduction in an inert atmosphere to obtain crude beryllium, (4) carrying out high-temperature vacuum refining, and (5) carrying out densification treatment.The preparation method can synchronously realize a metal beryllium product with the direct recovery rate gt of the beryllium and the purity gt of 82% and the purity gt of 99% on the premise of ensuring safety (no splashing).

The application discloses a high-activity hydrogenation catalyst and a preparation method and application thereof. The hydrogenation treatment catalyst contains at least molybdenum, nickel active metal, metal additive, carbon and inorganic refractory oxide carrier; the metal additive is at least one or more of zinc, copper, magnesium and gallium, and the hydrogen temperature programmed reduction (H2-TPR) of the catalyst should have the following properties: the peak area integral value of the reduction peak in the temperature range of 350-450 DEG C accounts for more than 50%, preferably more than 60%, further preferably more than 70%, more further preferably 65%-85%, and best preferably 70%-80% of the total peak area integral value in the temperature range of 150-650 DEG C. The hydrogenation catalyst not only has strong hydrogenation activity without sulfuration, but also has good stability compared with conventional noble metal and nickel catalysts when treating low-sulfur raw materials.

The invention provides a catalyst for preparing 3-methylpyridine through dehydrogenation as well as a preparation method and application of the catalyst. According to the catalyst, an active component and an auxiliary metal are loaded on a carrier, metal palladium is used as the active component, and at least one of copper, nickel, cobalt, platinum and lead is used as the auxiliary metal; wherein based on the mass percentage of the total mass of the catalyst, the loading capacity of the active component is 0.5%-1.2%, and the loading capacity of the auxiliary metal is 0.1%-0.5%. The prepared catalyst adopts a step-by-step loading method and temperature programmed reduction, after the catalyst runs for 4000 hours, the catalytic performance is stable, the conversion rate of the 3-methylpiperidine can be maintained to be greater than 99%, and the selectivity of the 3-methylpiperidine is more than 99%.

The invention relates to the field of heterogeneous catalyst preparation, in particular to a metal-loaded Fischer-Tropsch synthesis catalyst and a preparation method and application thereof. The catalyst comprises an alumina carrier and Co3O4 nanoparticles, wherein the mass ratio of the Co3O4 nanoparticles to the alumina carrier is 1: (3.5-5); the average particle size of the Co3O4 nanoparticles is 8-12 nm, and the difference value between the minimum particle size and the maximum particle size of the Co3O4 nanoparticles is 5-10 nm; in a hydrogen temperature programmed reduction H2-TPR test, the temperature corresponding to the highest value of the first reduction peak of the catalyst is 250-350 DEG C, and the integral area of the reduction peak corresponding to the temperature of 100-400 DEG C accounts for 55-75% of the total integral area of all the reduction peaks. The particle sizes of Co3O4 nanoparticles in the catalyst are intensively distributed in an interval suitable for the Fischer-Tropsch synthesis reaction, and the catalyst has excellent catalytic performance when being used in the Fischer-Tropsch synthesis reaction.

A catalyst has a carrier and a hydrogenation active metal component supported on the carrier. The hydrogenation active metal component contains at least one Group VIB metal component and at least one Group VIII metal component, and the carrier is composed of phosphorus-containing alumina. When the hydrogenation catalyst is measured using a hydrogen temperature programmed reduction method (H2-TPR), the ratio of the peak height of the low-temperature reduction peak, Plow-temp peak, at a temperature of 300-500° C. to the peak height of the high-temperature reduction peak, Phi-temp peak, at a temperature of 650-850° C., i.e. S=Plow-temp peak / Phi-temp peak, is 0.5-2.0; preferably 0.7-1.9, and more preferably 0.8-1.8. The hydrogenation catalyst shows excellent heteroatom removal effect and excellent stability when used in hydrotreatment.

The invention provides a method for characterizing active oxygen species on the surface of a catalyst. The method comprises the following steps: introducing ethylene-oxygen into a catalyst for in-situ pretreatment; carbon monoxide is introduced into the pretreated catalyst for temperature-programmed reduction treatment, and gas and other gas phase products subjected to temperature-programmed reduction treatment are detected. According to the method, the surface oxygen activity and relative quantity of the catalyst are rapidly analyzed, and the reaction activity and selectivity of the catalyst are directly and clearly reflected.

The present application provides a reforming catalyst, a preparation method and application thereof. The catalyst contains a carrier and a reforming active component supported on the carrier. The reforming active component elements include iron and a transition metal. The reduction peak temperature of the surface active metal in the hydrogen temperature programmed reduction test is less than or equal to the reduction peak temperature of a sample with a corresponding active component dispersion of 50%. And / or the active metal is dispersedly distributed on the surface of the carrier. The method comprises: contacting a solution containing a source of the reforming active component with a source of the carrier in equal volumes, the polarity of the solvent in the solution or the weighted polarity in terms of mole fraction is weak polarity, and then drying and calcining. The present application provides a method for dry reforming of ethane and carbon dioxide. The preparation method of the catalyst of the present application controls the polarity of the mixed solvent in the one-step equal-volume co-impregnation, so as to obtain a surface structure with controllable active component distribution. The preparation method of the catalyst of the present application is simple, has little influence on the environment, and is suitable for large-scale production.

The invention discloses a core-shell structure copper-zinc-based methanol reforming catalyst and a preparation method thereof, and belongs to the technical field of catalysts, the catalyst comprises a gallium-doped copper-zinc composite oxide active core and a bifunctional shell layer, the bifunctional shell layer comprises a zinc oxide migration layer and a mesoporous silicon dioxide protection layer which are formed in situ through strong metal-carrier interaction, and the preparation method comprises the steps of preparing a precursor through a coprecipitation method, coating the mesoporous shell layer through an improved Stber method and inducing the SMSI effect through temperature programmed reduction. The catalyst shows excellent catalytic activity and long-term stability in a methanol steam reforming reaction.