253 results about "Reduction Activity" patented technology

A molecular sieve-containing catalyst for cracking hydrocarbons, comprising molecular sieve, refractory inorganic oxide, clay and a metal component, wherein the amount of said molecular sieve is from 1 to 90% by weight, the refractory inorganic oxide is from 2 to 80% by weight, the clay is from 2 to 80% by weight, and the metal component is from 0.1 to 30% by weight, calculated as the oxide of said metal having its maximum valence state, based on the total amount of the catalyst, wherein said metal component exists essentially in a reduction state and is one or more metals selected from the group consisting of metals of Group III A(other than aluminum), and metals of Group IVA, VA, IB, IIB, VB, VIB and VIIB, and non-noble metals of Group VIII of the periodic table. The catalyst has higher cracking activity and higher sulfur reduction activity.

The invention relates to a preparation method of catalyst by ultralow-sulfur hydrofining. Al2O3-SiO2-ZrO2 tertiary compound oxide as a carrier, W-Mo-Ni-Co quaternary elements as active metal components and P as aid are used to prepare the catalyst which is butterfly-shaped. The preparation method is characterized by introducing SiO2 to Al2O3 to modulate surface acidity of the carrier and increasing specific surface area and pore volume of the carrier; introducing ZrO2 to increase low-temperature reactivity of the catalyst; preparing metallic co-impregnated solution by complexing process, and loading W-Mo-Ni-Co quaternary active metal components and the aid P by means of stepwise saturated impregnation to increase dispersity and utilization rate of active metals. The catalyst has the advantages of large specific surface, large pore volume, moderate surface acidity, high metal reduction activity and high low-temperature reactivity. Compared with like catalysts, the catalyst can be used to produce ultralow-sulfur diesel with lower than 10microgram/g sulfur content under low reaction severity.

The sulfur content of liquid cracking products, especially the cracked gasoline, of the catalytic cracking process is reduced by the use of a sulfur reduction catalyst composition comprising a porous molecular sieve which contains a metal in an oxidation state above zero within the interior of the pore structure of the sieve as well as a rare earth component which enhances the cracking activity of the cracking catalyst. The molecular sieve is normally a faujasite such as USY. The primary sulfur reduction component is normally a metal of Period 4 of the Periodic Table, preferably vanadium. The rare earth component preferably includes cerium which enhances the sulfur reduction activity of the catalyst. The sulfur reduction catalyst may be used in the form of a separate particle additive or as a component of an integrated cracking/sulfur reduction catalyst.

The sulfur content of liquid cracking products, especially the cracked gasoline, of the catalytic cracking process is reduced by the use of a sulfur reduction catalyst composition comprising a porous molecular sieve which contains a metal in an oxidation state above zero within the interior of the pore structure of the sieve as well as a cerium component which enhances the stability and sulfur reduction activity of the catalyst. The molecular sieve is normally a faujasite such as USY. The primary sulfur reduction component is normally a metal of Period 3 of the Periodic Table, preferably vanadium. The sulfur reduction catalyst may be used in the form of a separate particle additive or as a component of an integrated cracking/sulfur reduction catalyst.

Disclosed is a non-noble metal catalyst for oxygen reduction. The catalyst comprises a flake-like graphene carrier; a nitrogen-doped carbon skeleton arranged between neighbor flake layers of the flake-like graphene carrier; the graphene flake layers are separated by the nitrogen-doped carbon skeleton; and nanometer particles are adhered to the flake layers of graphene. The nanometer particles are one or more than two of carbon-coated non-noble metal particles, carbon-coated non-noble metal carbide particles, and carbon-coated non-noble metal nitride particles. A preparation method of the non-noble metal catalyst for oxygen reduction comprises: adding graphite oxide and non-noble metal precursor salt into water; performing mixing and standing; adding nitrogen-containing micro-molecules, a Nafion solution, and an oxidizing agent; performing uniform mixing; allowing the obtained solution to be evaporated; performing freeze-drying; and performing temperature programming thermal treatment and other after-treatment to obtain the non-noble metal catalyst for oxygen reduction. The catalyst has advantages of high oxygen reduction activity, good mass transfer performance, and low price.

The invention discloses fuscoporia obliqua active ingredients capable of lowering blood sugar and a preparation method and application of the fuscoporia obliqua active ingredients. The preparation method takes fuscoporia obliqua fruit body as raw material and comprises the following steps: respectively extracting, filtering and concentrating the fuscoporia obliqua fruit body with normal temperature water and high temperature water; adding alcohol into concentrate and depositing to obtain crude polysaccharide; respectively pouring the polysaccharide extracted with normal temperature water and the crude polysaccharide extracted with high temperature water to flow through a (diethylaminoethanol) DEAE-52 cellulose column; carrying out subsection elution by using distilled water and NaCl solutions with different concentrations; and collecting stepwise elution peak sugar solution. Internal blood sugar reduction activity experiment shows that 0.2mol/L NaCl-section eluted sugar of the crude polysaccharide extracted with normal temperature water and 0.2mol/L NaCl-section eluted sugar of the crude polysaccharide extracted with high temperature water both have obvious blood sugar reduction activity, same blood sugar reduction activity with the blood sugar reduction medicine of metformin hydrochloride, and no obvious toxic or side effect.

The invention provides a preparation method of catalyst for the cathode of a direct methanol fuel cell, comprising the following steps: adding solvent into a reactor; adding with nitrogen; adding withM-salt and stabilizing agent in proportion; dropwise adding with reducing agent; reacting to prepare M nanometer catalyst solution; vacuuming and filtering to obtain M nanometer particles; dissolvingthe M nanometer particles into the solvent and stirring; adding with platinum base compound and stabilizing agent; ultrasonically stirring; adding with hydrazine hydrate solution and reacting; preparing black nanometer catalyst solution; separating and washing; and vacuum drying to obtain black powdered M-Pt core-shell structure nanometer particles catalyst. By using the characteristics that thenoble metal has higher catalytic activity to oxygen reduction and the transition metal has a special electronic structure, the method uses the transition metal with more d belt electron holes and lower electron negativity as core to prepare M-noble metal core shell structure nanometer particles which are used for oxygen electrode reduction catalyst of the direct methanol fuel cell, wherein the catalyst has higher oxygen reduction activity, methyl alcohol resistibility and stability, and the preparation method is simple and is low in cost.

The sulfur content of liquid cracking products, especially the cracked gasoline, of the catalytic cracking process is reduced by the use of a sulfur reduction catalyst composition comprising a porous molecular sieve which contains a metal in an oxidation state above zero within the interior of the pore structure of the sieve as well as a cerium component which enhances the stability and sulfur reduction activity of the catalyst. The molecular sieve is normally a faujasite such as USY. The primary sulfur reduction component is normally a metal of Period 3 of the Periodic Table, preferably vanadium. The sulfur reduction catalyst may be used in the form of a separate particle additive or as a component of an integrated cracking/sulfur reduction catalyst.

The invention relates to a method of raising zero-valent iron chromium removal catalytic reduction activity in neutral condition, characterized in that the electrolyte with 0.1 to 0.5 mol ferrous sulfate, 0.3 to 0.6 mol boric acid, 0.4 to 0.7 mol ammonium sulfate, 0.003 to 0.006 mol saccharin, 0.003 to 0.006 mol ascorbic acid, 0.002 to 0.004 mol sodium dodecyl sulfate per litre is deposited. Add the produced zero-valent iron into the solution with Cr (VI) in. Oxalic acid, citric acid, salicylic acid, tartaric acid or humic acid can also be added into the solution. The Ph of the solution is adjusted to 6.5 to 8.0 and the Cr (VI) content in the solution reduces remarkably. The method has the advantages of simple preparation technology, convenient operation and low cost. The produced zero-valent iron has a diameter less than 50 nm and is of uniform granularity and high catalytic activity. With 2.2 times chromium removal efficiency of ordinary methods, the method of raising zero-valent iron chromium removal catalytic reduction activity in neutral condition has a promising application prospect in remedying polluted soil and sewage.

The present invention provides a catalyst which is not corroded in an acidic electrolyte or at a high potential, is excellent in durability and has high oxygen reduction activity. The catalyst of the present invention comprises an oxycarbonitride of titanium. The oxycarbonitride of titanium is preferably represented by the composition formula TiC_xN_yO_z (wherein x, y and z represent a ratio of the numbers of atoms and are numbers satisfying the conditions of 0<x≦1.0, 0<y≦1.0, 0.1≦z<2.0, 1.0<x+y+z≦2.0 and 2.0≦4x+3y+2z). The catalyst is preferably a catalyst for a fuel cell.

The invention discloses a non-precious metal oxygen reduction catalyst and a preparing method and application thereof. The preparing method comprises the following steps that 1, conductive carbon is dispersed into water, and a carbon source and ferric salt are added to carry out a hydrothermal reaction, so that a precursor is obtained; 2, heat treatment is carried out on the precursor and a nitrogen source to obtain the non-precious metal oxygen reduction catalyst. An iron source is dispersed into a solution phase, a hydrothermal method is used for compounding the iron source and an obtained carbon layer, then high-temperature treatment is carried out, nitrogen is doped to prepare a FeN4 active site, and compared with other methods of directly mixing the iron source with the carbon source and the nitrogen source in a solid phase mode, the method is more uniform in compounding, and effectively prevents iron atoms from aggregating at high temperature and growing up; moreover, the hydrothermal method and high-temperature treatment are convenient to control. The prepared catalyst is excellent in catalytic performance and has higher oxygen reduction activity compared with that of other existing non-precious metal catalysts.

The invention discloses sulfydryl-ferrum composite and modified clay and a preparation method thereof. The preparation method comprises the steps of: firstly mixing a sulfhydryl compound solution in the concentration of 0.5-2.0 mol/L with a clay suspension liquid with the mass percentage of 1-3% according to the volume ratio of 1: (5-10), then stirring for 1.5-4 hours, carrying out solid-liquid separation, removing upper-layer aqueous phase components, drying solid matters at 40-60 DEG C and grinding the solid matters into powder after washing the solid matters, mixing ground powdery solid matters with water to form a suspension liquid with the mass ratio of 2%, mixing the suspension liquid with the hydroxy acid iron solution in the concentration of 1.0-2.0 mol/L, carrying out the solid-liquid separation after stirring for 1.5-4 hours, and grinding the solid matters into the powder after drying the solid matters at 40-60 DEG C, so as to obtain the sulfydryl-ferrum composite and modified clay. The clay has large loading capacity and reduction activity, can effectively adsorb the heavy metal Cr (VI) polluting the environment, and can convert the Cr (VI) into Cr(III) with low toxicity.

The invention discloses a metal sulfide electrode with a hydrogen reduction catalytic function and a preparation method of the metal sulfide electrode, belonging to the fields of inorganic chemistry and catalysis. The electrode contains metal titanium, porous anatase TiO2 nanotubes grown on the surface of titanium and metal sulfide nanoparticles loaded on the surfaces of the nanotubes. The preparation method comprises the following steps: firstly preparing the anatase TiO2 nanotubes with a porous structure on the surface of metal titanium by an electrochemical anode oxidation method; then placing the TiO2 nanotubes into a solution containing molybdenum ions or tungsten ions, and irradiating ultraviolet light on the surface; and reducing the molybdenum ions or the tungsten ions by utilizing the photocatalytic reduction of the TiO2 nanotubes under the ultraviolet light to generate MoS2 or WS2 nanoparticles. The metal sulfide electrode prepared by the preparation method disclosed by the invention shows hydrogen reduction catalytic activity and has the characteristics of low cost, simple preparation method and environmental friendliness. In the metal sulfide electrode disclosed by the invention, a metal sulfide catalyst is directly loaded on a conductive porous substrate to form the electrode and can be directly applied to hydrogen reduction reaction, and the catalyst particles do not need to be fixed.

The invention relates to a metal-doped nitrogen-containing carbon-based catalyst of a fuel cell and application of the catalyst. The catalyst adopts organic surface active agents as a protection agent and a structural guide agent and adopts an aromatic compound and aldehyde as reaction monomers, metal elements are added in the reaction process to obtain a polymer-metal compound, and the polymer-metal compound is dried and then is subjected to high-temperature processing with inert gas or/and ammonia gas to finally obtain the metal-doped nitrogen-containing carbon-based catalyst. When the metal-doped nitrogen-containing carbon-based catalyst is used as a cathode catalyst of a proton exchange membrane fuel cell and a direct-methanol fuel cell, the oxide reduction activity, stability and toxicity resistance are excellent; moreover, the catalyst has an environment-friendly effect, is low in cost, controllable in aperture, high in specific surface area and rich in resource and can substitute for platinum to serve as an electric catalyst of the proton exchange membrane fuel cell.

The invention provides a lithium iron phosphate composite material coated with a ternary carbon source and a preparation method of the material and belongs to the technical field of positive materials for lithium ion cells, aiming at the defects of poor conductivity and low tap density of lithium iron phosphate. The invention provides a modification method of the lithium iron phosphate composite material coated with the ternary carbon source according to the characteristics including pyrolysis characteristics, carbonization degrees, dispersion manners, residual carbon structures, reduction activity and the like of different carbon sources, based on a process and reaction process of preparing the lithium iron phosphate by using a carbon heat reduction method; micro-molecular water-soluble organic matters, high-molecular polymers, graphene compounds, iron source compounds, phosphorus source compounds and lithium source compounds are ball-grinded and homogenized and then are dried to prepare a composite precursor; then the composite precursor is sintered to obtain the lithium iron phosphate composite material. According to the lithium iron phosphate composite material coated with the ternary carbon source, the problems that the conductivity of the lithium iron phosphate composite material is low, the lithium ion diffusion coefficient is low, the tap density is low, and the like are solved.

A method of removing nitrates from water by utilization of a zero-valent iron/oxidizing agent/zeolite synergetic system is provided. The zero-valent iron is common iron powder. The oxidizing agent is a common oxidizing agent used in water treatment. The zeolite is natural zeolite or artificial zeolite. The method is characterized in that: the oxidizing agent in the system oxidizes and strips a passivation layer formed on the surface of the zero-valent iron to allow electrons in the zero-valent iron to be transferred continuously to the outside, so that the zero-valent iron maintains high reduction activity to reduce the nitrates into ammonia nitrogen. Then efficient selective absorption of the zeolite to the ammonia nitrogen is utilized to remove the ammonia nitrogen in the water body. The method is environmental friendly, simple, feasible, low in cost, and capable of being efficiently used for treatment of waste water containing nitrates of industrial enterprises and nitrate restoration and removal for underground water.

The invention belongs to the field of precious metal electrocatalysts, and relates to a preparation method and application of a precious metal electrocatalyst. The preparation method comprises the steps: mixing a carbon carrier, an alkaline substance and a precious metal salt aqueous solution evenly, to prepare a suspension; at the temperature of 50-200 DEG C, carrying out reflux condensation for 0.5 h or more, carrying out standing precipitation, and removing the supernatant; then adding a reducing agent, stirring for 0.5 h or more, to eventually obtain a precipitate, carrying out suction filtration, washing to neutral, and carrying out vacuum drying; and in a mixed atmosphere of one or more than two of nitrogen gas, ammonia gas, helium gas, argon gas and hydrogen gas and at the temperature of 100-800 DEG C, carrying out heat treatment for 0.5-5 h, and thus obtaining the precious metal electrocatalyst. The prepared precious metal electrocatalyst can be applied in fuel cells. The preparation method is simple to operate, is environmentally friendly, and is suitable for mass production; the loading capacity of active components of the precious metal electrocatalyst is 0.01-90 wt %, and the carrier selection range is extensive; and the precious metal electrocatalyst has higher oxygen reduction activity, and can be applied in the fuel cells.

The invention discloses a metal-doped nitrogen-containing carbon gel catalyst used for proton exchange membrane fuel cell cathode and its preparation method, a nitrogenous aromatic compound and aldehyde are taken as a reaction precursor, a reaction monomer is subjected to an addition reaction and a condensation polymerization through base catalysis, and a metallic element is simultaneously added to prepare a metal-doped hydrogel, the metal-doped hydrogel is subjected to processes of drying, pyrolysis and secondary nitridation to obtain the metal-doped nitrogen-containing carbon gel nano charcoal material. When the catalyst of the present invention is used as the anode catalyst of the proton exchange membrane fuel cell, the catalyst indicates excellent reduction activity, the catalyst has the advantages of environmental protection, low cost, microscopic control and abundant resource, and is expected to be an electrocatalyst of the proton exchange membrane fuel cell.

A System and Method for monitoring risk reduction activities in one or more medical practice settings and environments is described. The system automatically monitors communications and equipment to verify proper clinical treatment processes and activities that reduce the risk of poor clinical outcomes or increased risk to health. The system can also automatically monitor out-patient activities. Clinical activities are monitored and various rules and risk reduction metrics calculated from the data. Real-time monitoring further permits alarms to be triggered if certain clinical steps considered proper are not followed in a particular case.

The invention relates to a 'copper and iron modified titanium dioxide pillared bentonite catalyst and a preparation method thereof', and belongs to the catalyst field of ammonia selective catalytic reduction of nitrogen oxides to nitrogen gas. The catalyst consists of X/Cu-Fe-TiO2-PILC, wherein, percentage content of X is 0-10% by weight, the percentage content of Cu is 0.05-30% by weight, the percentage content of Fe is 0.05-30% by weight, the content of Ti is 5-50% by weight, and precursors of Cu and Fe are Cu salts and Fe salts; wherein, X represents a rare earth metal oxides. Compared with conventional vanadium-based catalysts, the catalyst has higher reduction activity on nitrogen oxides. Cu-TiO2-PILC has higher low-temperature catalytic activity, Cu-Fe-TiO2-PILC has a wider activation temperature range, and the rare earth metal oxide is added, which can further improve the catalytic activity.

The vacuum chemical plating process for preparing composite metal film includes the first pre-modification of porous film by means of sol-gel technology to introduce one transition layer containing metal crystal seed with self-catalytic reduction activity to the chemical plating, and the subsequent vacuum chemical plating by means of forming different vacuum degrees on two sides of the modified porous composite film. The process can raise the hydrogen permeating performance of the composite metal film and raise the stability of the composite metal film.

The invention relates to a carbon-doped ultrathin bismuth tungstate nanosheet photocatalytic material and a preparation method thereof. The modified carbon-doped ultrathin bismuth tungstate nanosheet photocatalytic material is characterized by being doped with carbon and prepared by piling ultrathin flaky bismuth tungstate nanosheets bent and agglomerated to some degree. The novel visible-light responsive carbon-doped ultrathin bismuth tungstate nanosheet photocatalytic material is of a flaky structure, has more active sites and large specific surface area, excellent CO2 capturing capability and visible-light response and charge transfer capability and low photoproduced electron-hole pair compounding efficiency, the solar energy utilization rate is greatly improved, the material is used for photocatalytic reduction of CO2, and the photocatalytic reduction activity of the CO2 can be obviously improved.