7 results about "Cryptomelane" patented technology

The invention discloses an ethylbenzene dehydrogenation catalyst as well as a preparation method and application thereof. The catalyst is prepared from Fe2O3, K2O, CeO2, MoO3 and a doped cryptomelane oxide. The catalyst provided by the invention is used in a reaction for preparing styrene by ethylbenzene dehydrogenation, and has the characteristics of high activity, high stability and good carbon deposition resistance.

The invention discloses a manganese-potassium hidden ore-based core-shell catalyst for synergistically removing NOx and VOCs at medium and low temperatures as well as a preparation method and application of the manganese-potassium hidden ore-based core-shell catalyst. According to the catalyst, manganese potassium hidden ore loaded copper oxide (Cu-OMS-2) is taken as a core, TiO2 is taken as a shell, a Cu-OMS-2-coated TiO2 core-shell composite structure is formed, the TiO2 accounts for 20%-35%, the doping amount of CuO is 5%-20%, and the balance is manganese potassium hidden ore (OMS-2). Active sites are separated by utilizing space confinement coupling interface electron confinement under the condition of 175-300 DEG C, efficient synergistic removal of NOx and VOCs is realized, the efficiency is greater than 90%, mutual inhibition between two reactions is remarkably relieved, generation of secondary pollutants is reduced, and the catalyst has excellent stability. The catalyst is suitable for medium and low temperature industrial flue gas purification, and has a good industrial application prospect.

The invention discloses a catalyst grading method for purifying methanol and application. The grading method comprises the following steps: sequentially arranging a first catalyst and a second catalyst along a material flow direction; the first catalyst is an MFI type molecular sieve catalyst; the second catalyst comprises a cryptomelane molecular sieve KOMS-2. According to the invention, methanol in-situ catalytic oxidation cyclic regeneration is realized, and the oxidation rate and mineralization rate of methanol and the adsorption capacity of the catalyst to methanol are obviously improved.

The application discloses a kind of low-temperature synergic removal NO x And VOCs of cryptomelane-based core-shell catalyst and its preparation method and application.The catalyst is with cryptomelane supported copper oxide (Cu-OMS-2) as core, TiO2 as shell, and forms Cu-OMS-2@TiO2 core-shell composite structure, wherein TiO2 accounts for 20%~35%, CuO doping amount is 5%~20%, and the balance is cryptomelane (OMS-2).By using space limit under the condition of 175~300 ℃, the active sites are separated by coupling interface electron limit, the efficient synergic removal of NO x And VOCs is realized, and the efficiency is greater than 90%, which significantly relieves the mutual inhibition between the two types of reactions, reduces the generation of secondary pollutants, and has excellent stability.The catalyst is suitable for low-temperature industrial flue gas purification and has good industrial application prospect.

The invention discloses a ternary lead-free BiFeO3-based perovskite-pyrochlore composite ceramic material as well as a preparation method and application thereof, the stoichiometric formula of the material is (1-x) (0.67 BiFeO3-0.33 BaTiO3)-xSmNbO4, x represents molar percentage and is 0.03-0.07, x represents molar percentage, x represents molar percentage, and x represents molar percentage. The preparation method comprises the following steps: carrying out ball milling on raw materials, drying, sieving, calcining in air at 800-850 DEG C for 3-4 hours, adding 0.1 wt% of manganese dioxide, carrying out secondary ball milling, drying, sieving, pouring into a mold, carrying out compression molding, demolding, and carrying out cold isostatic pressing to obtain a blank body; embedding the green body into powder with the same components, putting the powder into a muffle furnace, and keeping the temperature for 2-4 hours at 1020-1040 DEG C in an air atmosphere to obtain the ternary lead-free BiFeO3-based perovskite-pyrochlore composite ceramic material. According to the invention, rhombohedral phase / pseudo-cubic phase (R / PC) regulation and control are combined with a perovskite-pyrochlore composite structure, so that a high dielectric constant, excellent breakdown strength and excellent frequency-temperature stability are obtained, and polarization intensity and energy storage density are improved at the same time.

The application discloses a method for degrading organic pollutants containing carbonyl and carboxyl by using cryptomelane oxygen vacancies, and adds cryptomelane into wastewater containing organic pollutants containing carbonyl and carboxyl, mixes sufficiently to generate hydrogen peroxide, and further degrades the organic pollutants by the hydrogen peroxide; the cryptomelane is an octahedral molecular sieve of manganese oxide mineral, and the crystal form is alpha-MnO2. The application utilizes the catalytic ability, oxidation ability and adsorption ability of the cryptomelane itself to degrade pollutants, and simultaneously utilizes the catalytic ability of the cryptomelane oxygen vacancies to generate hydrogen peroxide from pollutants containing carbonyl and carboxyl to remove the pollutants deeply, and the whole reaction process simultaneously utilizes the oxidation, adsorption and catalytic properties of the cryptomelane. Therefore, the application has the advantages of cheap and easily available required catalyst, wide pH application range, small required catalyst amount, no need of additional other oxidants, low reaction activation energy, completion under normal temperature and pressure air conditions, simple operation, high catalytic efficiency, recyclable catalyst and the like.

The present application relates to dehydrogenation catalysis technical field, specifically relates to a kind of dehydrogenation catalyst and preparation method and application and the method for preparing styrene by dehydrogenation of ethylbenzene, with the total weight of catalyst as benchmark, in the catalyst, cryptomelane-type oxide content is 4.2wt%-8.5wt%;Fe2O3 Content is 56wt%-72wt%;K2O content is 5.6wt%-10wt%;CeO2 Content is 6wt%-11wt%;MoO3 Content is 2wt%-6.5wt%;Co3O4 Content is 2wt%-4.4wt%;ZrO2 Content is 1.8wt%-3.2wt%;CaO content is 0.3wt%-1.2wt%.The dehydrogenation catalyst described in the present application is applied in the reaction of alkylbenzene (ethylbenzene) dehydrogenation to prepare alkenylbenzene (such as styrene), with the characteristics of high catalytic activity, good stability, not easy to be deactivated.