5250 results about "Precious metal" patented technology

The invention relates to a method for preparing alcohol by acetic acid gas phase hydrogenation. A reaction system comprises acetic acid, hydrogen and a catalyst; the reaction temperature is 120-300 DEG C; the reaction pressure is 1.0-20.0MPa; the space velocity of acetic acid liquid is 0.5-10.5h<-1>; the molar ratio of H2 to acetic acid is 1-250; the catalyst takes activated carbon as a carrier; and main active components comprise one or two of transitional metals such as W and Mo. The addition agent is one of or more of precious metals such as Pd, Re, Pt, Rh and Ru and the like; and the acetic acid and the hydrogen can be converted into alcohol with high activity and selectivity under the action of the catalyst.

A catalyst has a base catalyst layer containing platinum and barium as precious metal supported by alumina and an over catalyst layer containing platinum and rhodium as precious metal supported by zeolitr. The platinum and rhodium in the over catalyst layer activate NOx and HC so as to make them more reactive in terms of energy, and the barium in the base catalyst layer makes the platinum be more dispersive in the base catalyst layer. Under the existence of dispersive platinum, NOx in exhaust gas is decomposed and purified by reaction with reactive NO2 and partially oxidized HC generated in the over catalyst layer.

A process for preparing metal nanoparticles, comprising reacting suitable metal salts and anionic surfactant containing an anionic group of carboxylic group (COO-), sulfate group (SO42-) or sulfonate group (SO32-) as reducing agent in water under reflux at a temperature of 50-140° C., such that under the reducing power of said anionic surfactant itself, the metal salts can be effectively reduced into metal nanoparticles having a uniform particle size and that the reaction will be not too fast, no large microparticle will be formed, the yield will not be lowered, and the nanoparticle thus prepared can be dispersed stably in polar and non-polar solvent.

A catalyst for purifying exhaust gases of a diesel engine. The catalyst contains two functional layers superimposed on an inert supporting body, whereby the first layer, which is situated directly on the supporting body, has a nitrogen oxide storage function and the second layer, which is in direct contact with the exhaust gas, has a catalytic function. The second functional layer additionally has a hydrocarbon-storage function and its catalytic function is provided by catalytically active noble metals of the platinum group which are deposited in highly dispersed form on finely divided, acidic carrier materials. Nitrogen oxides in the oxygen-rich exhaust gas of a diesel engine can be converted with optimal utilization of the reductive constituents contained in the exhaust gas. For this purpose, no reducing agents going beyond the reductive components (carbon monoxide and hydrocarbons) which are contained as a consequence of incomplete combustion need to be added to the exhaust gas. Nevertheless, rates of conversion in respect of the nitrogen oxides are obtained, averaged over practical driving cycles, which lie distinctly above the rates of conversion of conventional reduction catalysts.

A shift converter (16) in a fuel processing subsystem (14, 16, 18) for a fuel cell (12) uses an improved catalyst composition (50) to reduce the amount of carbon monoxide in a process gas for the fuel cell (12). The catalyst composition (50) is a noble metal catalyst having a promoted support of mixed metal oxide, including at least both ceria and zirconia. Cerium is present in the range of 30 to 50 mole %, and zirconium is present in the range of 70 to 50 mole %. Additional metal oxides may also be present. Use of the catalyst composition (50) obviates the requirement for prior reducing of catalysts, and minimizes the need to protect the catalyst from oxygen during operation and/or shutdown.

High-surface-area carbon nanostructures coated with a smooth and conformal submonolayer-to-multilayer thin metal films and their method of manufacture are described. The preferred manufacturing process involves the initial oxidation of the carbon nanostructures followed by immersion in a solution with the desired pH to create negative surface dipoles. The nanostructures are subsequently immersed in an alkaline solution containing non-noble metal ions which adsorb at surface reaction sites. The metal ions are then reduced via chemical or electrical means and the nanostructures are exposed to a solution containing a salt of one or more noble metals which replace adsorbed non-noble surface metal atoms by galvanic displacement. Subsequent film growth may be performed via the initial quasi-underpotential deposition of a non-noble metal followed by immersion in a solution comprising a more noble metal. The resulting coated nanostructures may be used, for example, as high-performance electrodes in supercapacitors, batteries, or other electric storage devices.

The invention provides a noble metal-containing supported catalyst which contains one of the noble metals from the group Au, Ag, Pt, Pd, Rh, Ru, Ir, Os or alloys of one or more of these noble metals in the form of noble metal particles on a powdered support material. The particles deposited on the support material have a degree of crystallinity, determined by X-ray diffraction, of more than 2 and an average particle size between 2 and 10 nm. The high crystallinity and the small particle size of the noble metal particles lead to high catalytic activity for the catalyst. It is particularly suitable for use in fuel cells and for the treatment of exhaust gases from internal combustion engines.

A process for converting renewable resources such as vegetable oil and animal fat into paraffins in a single step which comprises contacting a feed which is a renewable resources with hydrogen and a catalyst which comprises molybdenum, a non-precious metal and an oxide to produce a hydrocarbon product having a ratio of even-numbered hydrocarbons to odd-numbered hydrocarbons of at least 2:1.

A catalyst layer on a substrate material which contains a proton-conducting polymer (ionomer), electrically conductive carbon particles and fine particles of at least one precious metal. The catalyst layer is obtainable by coating the substrate material with an ink which contains a dispersion of the carbon particles and at least one organic precious metal complex compound in a solution of the ionomer, and drying the coating below a temperature at which the ionomer or the substrate material is thermally damaged, the precious metals in the complex compounds being present with an oxidation number of 0 and the complex compounds being thermally decomposed during drying to form the fine precious metal particles.

Zoned diesel oxidation catalysts containing a higher precious metal loading in the inlet zone that the outlet zone and an equal or shorter length inlet zone are described. Emission treatment systems and methods of remediating nitrogen oxides (NOx), particulate matter, and gaseous hydrocarbons using zoned diesel oxidation catalysts are also described.

The invention discloses a preparation method of a catalyst with a core-shell structure for a low-temperature fuel cell, belonging to the technical field of fuel cells. In the catalyst with the core-shell structure prepared with the preparation method, platinum is taken as a shell, a metal alloy consisting of more than one of metals including ruthenium, platinum, iron, cobalt, nickel, copper, tin, iridium, gold and silver is taken as an inner core, and the shell and the inner core are loaded on a carbon carrier. The preparation method comprises the following preparation steps of: reducing a metal chloride or a metal nitrate with a reducing agent, and forming a core on the carbon carrier with a large specific surface area; stabilizing the core; and precipitating Pt on a core layer with a impregnation reduction method, a high-pressure organic sol method, a microwave method or an electrodeposition process to form the catalyst with the core-shell structure. Due to the adoption of the preparation method, the utilization ratio of noble metal platinum is increased, the cost of an electro-catalyst is reduced effectively, and the methanol oxidizing capability and oxygen reducing activity of the obtained catalyst are increased by 10.8 times and 8.7 times in maximum respectively in comparison to the mass ratio and activity of a commercial JM4100Pt/C catalyst.

The invention relates to hydrogen production and hydrogen storage technologies and materials, in particular to a catalyst for catalytic hydrolysis of borane for the hydrogen production and a preparation method thereof, thereby solving the problems that the direct application of powder catalyst in a catalytic hydrolysis solid-liquid reaction system can cause the loss of the catalyst, the catalytic hydrolysis reaction is difficult to control and the hydrolysis by-products are difficult to be recovered, etc. The catalyst is composed of an active component and a carrier; the active component is a binary, ternary or multinary alloy or a single precious metal or the combination thereof which is composed of one or more transition metals, rare earth metals or precious metals and metalloids; the active component is deposited on the carrier through the improved chemical plating technology, the surface thereof is rough and porous, and the structure of the prepared catalyst is the amorphous or the nanocrystalline structure. The preparation method has simple preparation process, high preparation efficiency and convenient large-scale preparation; the sources of the used raw materials are rich; the catalytic activity of the prepared supported catalyst is high, the real-time control of the catalytic hydrolysis reaction of the borane can be realized, the catalytic performance is stable, and the catalyst can be repeatedly used for a plurality of times.

A pre-chamber spark plug that includes a shell. Additionally, the pre-chamber spark plug includes an insulator disposed within the shell. In a particular embodiment, a center electrode has a first portion surrounded by the insulator, and a second portion that extends from the insulator into a pre-chamber. The pre-chamber defined by the shell. In a further embodiment, a ground electrode is attached to the insulator. In particular embodiments, the ground electrode is tubular in shape and includes an inner spark surface ring spaced in surrounding relation to the center electrode to create a spark gap, an outer ring attached to the shell, and a plurality of rounded spokes connecting the inner and outer rings. In a particular embodiment, the ground and center electrodes accommodate attachment of precious metal alloys to increase electrode surface life. In another embodiment the ground electrode and insulator is coaxial to the center electrode.

High-stability, self-protecting particles encapsulated by a thin film of a catalytically active noble metal are described. The particles are preferably nanoparticles comprising a passivating element having at least one metal selected from the group consisting of columns IVB, VB, VIB, and VIIB of the periodic table. The nanoparticle is preferably encapsulated by a Pt shell and may be either a nanoparticle alloy or a core-shell nanoparticle. The nanoparticle alloys preferably have a core comprised of a passivating component alloyed with at least one other transition metal. The core-shell nanoparticles comprise a core of a non-noble metal surrounded by a shell of a noble metal. The material constituting the core, shell, or both the core and shell may be alloyed with one or more passivating elements. The self-protecting particles are ideal for use in corrosive environments where they exhibit improved stability compared to conventional electrocatalyst particles.

A catalyst for the catalytic combustion of combustible waste gas is prepared by dipping the Pt as active component on the coated layer of cellular ceramics as carrier. The said coated layer contains Al2O3 (20-80 wt.%), TiO2 (10-40 wt.%), CeO2 (5-30 wt.%) and ZrO2 (5-20 wt.%). Its advantages are high utilization rate of Pt, and high distribution uniformity.

The invention discloses a hydroisomerization catalyst, a preparation method and an application thereof. The preparation method comprises the following steps: a) providing a catalyst precursor containing a carrier, and a compound containing noble metals in the VIII group and a compound containing a second metal which are both supported on the carrier, wherein the two compounds hereinabove are both non-oxides, the second metal is one or more than two selected from the metal in the VB group, the metal in the VIB group, non-noble metal in the VIII group and lanthanum-series metals, the carrier containing mesoporous molecular sieve; and b) roasting the catalyst precursor in an atmosphere formed by a gas containing an oxidizing gas and a halogen-containing compound. The invention also discloses a hydroisomerization method for hydrocracked tail oil with the hydroisomerization catalyst. The hydroisomerization catalyst, when being used in the hydroisomerization for the hydrocracked tail oil, can be used for producing an isomerized product having high viscosity index and low pour point, which is suitable for being used as lubricant basic oil.

The invention relates to a lead-free solder alloy for welding the electronic elements and its manufacturing method. The lead-free solder alloy is characterized in that the main components are Sn, Ag, Cu, and Ni, and In, Bi, Pd, P, Ge, Ga, Se, Te, La, Ce, Pr, Nd, Pm, Sm, Eu, Tm are added selectively. The preparation method is characterized by taking Sn, Ag, Cu, Ni and the additional elements in proportion and smelting them at the temperature of 1300 C. to 1500 C. to obtain the intermediate alloy by using water glass covering process; melting the residual Sn and the intermediate alloy at the temperature of 300 C. to 350 C. by using water glass covering process, and casting the molten materials into alloy pig and soldering tin rod at the temperature of between 250 C. and 350 C.. The lead-free solder alloy provided by the invention can be used for welding the Ag and Pd noble metal electronic element.

The invention discloses a mercury-free catalyst with low bullion content for acetylene hydrochlorination and application thereof and belongs to the technical field of a catalyst for the acetylene hydrochlorination and a preparation technique and a reaction process thereof. The catalyst comprises a noble metal element which accounts for 0.05 to 0.5 weight percent of the total weight of the catalyst, a common metal element which accounts for 0.1 to 5 weight percent of the total weight of the catalyst, and a carrier, wherein the noble metal element and the noble metal element exist in the form of metallic compounds. The noble metal element content of the catalyst is reduced greatly, the loading amount of a cocatalyst metallic element is also low, and the cost of the catalyst is reduced greatly; and the catalyst can replace the highly toxic mercury catalyst and is applied to the industrial production of the acetylene hydrochlorination.

A time display device (“TDD”)—equally adaptable to watches, clocks, computers, phones, and vehicles—indicates the current hour of the day by displaying a color that refers an observer to the disclosed color-to-hour matrix, thereby eliminating the traditional hour hand or digit altogether. Alternately adaptable to months, the system may be used with both mechanical and electronic displays. Various disclosed minute indicators provide minute indication by shape, complexity, company logo, air bubbles, or other novel methods. Environmental sensors allow switching between functions. TDD appearance is user-customizable via Internet. Birthstones, gemstones, and precious metals are alternately used as stand-alone time indicators.

A method of noble metal layer formation for high aspect ratio interconnect features is described. The noble metal layer is formed using a cyclical deposition process. The cyclical deposition process comprises alternately adsorbing a noble metal-containing precursor and a reducing gas on a substrate structure. The adsorbed noble metal-containing precursor reacts with the adsorbed reducing gas to form the noble metal layer on the substrate. Suitable noble metals may include, for example, palladium (Pd), platinum (Pt) cobalt (Co), nickel (Ni) and rhodium (Rh).

A catalyst carrier which comprises particles of a silicon-containing ceramic material. Each of these particles is covered by a film of alumina on which a noble metal is carried.

A catalyst element (30) for high temperature applications such as a gas turbine engine. The catalyst element includes a metal substrate such as a tube (32) having a layer of ceramic thermal barrier coating material (34) disposed on the substrate for thermally insulating the metal substrate from a high temperature fuel/air mixture. The ceramic thermal barrier coating material is formed of a crystal structure populated with base elements but with selected sites of the crystal structure being populated by substitute ions selected to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a higher rate than would the base compound without the ionic substitutions. Precious metal crystallites may be disposed within the crystal structure to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a lower light-off temperature than would the ceramic thermal barrier coating material without the precious metal crystallites.

The invention relates to a carbon supported catalyst for ozone oxidation, and a preparation method and a use thereof. The carbon supported catalyst is composed of an active carbon supported Fe, Cu, Ni or Mg transition metal active component and a Ce, La or K cocatalyst. The catalyst has a very high catalysis activity against non-degradable organic wastewater, allows the COD removal rate to reach above 55% and the biodegradability of the wastewater to be improved to above 0.30, has the advantages of long service life, simple preparation, no secondary pollution, containing of no precious metals, and low production cost, and is very suitable for the use in the industrialized production.

New and improved applications of Raman Scattering are disclosed. These applications may be implemented with or without using an enhanced nano-structured surface that is trademarked as the RamanNanoChip™ disclosed in a pending patent. As a RamanNanoChip™ provides much higher sensitivity in SERS compared with conventional enhance surface, broader scopes of applications are now enabled and can be practically implemented as now disclosed in this application. Furthermore, a wide range of applications is achievable as new and improved Raman sensing applications. By applying the analysis of Raman scattering spectrum, applications can be carried out to identify unknown chemical compositions to perform the tasks of homeland security; food, drug and drinking materials safety; early disease diagnosis; environmental monitoring; industrial process monitoring, precious metal and gem authentications, etc.

The invention discloses a loaded reduced precious metal catalyst. The active component of the catalyst is one or more selected of reduced precious metal platinum, palladium, gold and silver, the active component accounts for 0.01-10% of the total weight of the catalyst, and the loaded reduced precious metal catalyst is prepared by adopting a low-temperature liquid phase reduction method. The invention also discloses a preparation method and application of the loaded reduced precious metal catalyst. The loaded reduced precious metal catalyst has high efficiency for removing formaldehyde in theair and can be widely applied to purification of formaldehyde in an industrial process and indoor air. The loaded reduced precious metal catalyst disclosed by the invention also has the advantages ofgood stability, simple preparation process, mild preparation and reaction conditions, low precious metal content, low use cost and the like.

A high exhaust gas-purifying efficiency is achieved. An exhaust gas-purifying catalyst includes a substrate, an oxygen storage layer covering the substrate and including an oxygen storage material, and a catalytic layer covering the oxygen storage layer and including palladium, rhodium and a carrier supporting them, the catalytic layer having a precious metal concentration higher than that of the oxygen storage layer.

A catalyst system to provide emission reductions under lean and stoichiometric conditions. The catalyst system comprises a forward catalyst having a first cerium-free zone including oxides of aluminum, alkali metals and alkaline earth metals and precious metals and a second zone with a lower loading of precious metals, oxides of aluminum, alkali metals or alkaline earth metals. This forward catalyst stores NOx emissions under lean conditions for subsequent reduction and converts HC, CO and NOx during stoichiometric operation. The second downstream catalyst includes precious metals, reduces emissions under stoichiometric conditions, and stores any residual NOx emitted from the first catalyst for subsequent reduction. In another embodiment, a forward catalyst has top and bottom layers designed to reduce emissions under lean conditions. In this embodiment, a second downstream catalyst is used to reduce emissions under stoichiometric conditions. In yet another catalyst, multiple zones are created within a single catalyst.

The invention relates to a preparation method of a noble metal modified titanium dioxide photocatalyst, which refers to a photo-catalytic oxidation-reduction coupling method realized in a photo-catalytic reactor: firstly, TiO2, noble-metal water soluble salt and organism are used for preparing a suspension which is then ultrasonically vibrated after the pH value is regulated to 1-12, put into a photo-catalytic reactor for reaction for 0.5h to 8h at 0 DEG C to 90 DEG C under the irradiation of an ultraviolet source with the power of 8W to 125W or a medium or high-voltage mercury lamp source with the power of 100W to 600W, and then separated, washed and dried to obtain the TiO2 photocatalyst modified by noble metal Ag, or Au, or Pt or Pd, wherein, the content of TiO2 is 90 percent to 99.99 percent, the content of the noble metal is 0.01 percent to 10 percent. The noble metal modified titanium dioxide photocatalyst has high photocatalytic degradation activity and strong surface hydrophobicity and the attached catabolites are easy to clean.

Thermal catalysts, particularly catalysts coated with precious metals, are used to reduce the concentration of CO, HC and NOx in exhaust gases from internal-combustion engines. While catalysts coated with precious metals exhibit catalytic activity from about 140 DEG C., to ensure very low emission levels thermal catalysts need to be heated during cold starting so that the pollutants produced during the cold start react. The specification discloses a catalyst with a photocatalytic semiconductor illuminated with UV light for this purpose. Suitable for use as the photocatalytic material is e.g. titanium dioxide. This enables pollutant levels to be reduced immediately after the engine has been started and even at relatively low ambient temperatures. The invention is suitable for use with diesel engines and lean-mixture spark-ignition engines.

A catalyst with high activity for cleaning the tail gas of car is prepared through preparing the coated composite alumina layer containing Ce, Zr and one or more of La, Pr, Y, Fe, Mn, Cu and Ba on the cellular cordierite ceramic carrier, and chemically plating Pd.