455results about How to "Low ignition temperature" patented technology

A combustor method and apparatus is provided. The method utilizes flameless combustion with one or more of three improvements to enhance ignition of the flameless combustor. A catalytic surface can be provided within a combustion chamber to provide flameless combustion at least in the vicinity of the catalytic surface at a temperature that is much lower than the autoignition temperature of fuel in air without the presence of the catalytic surface. Nitrous oxide or supplemental oxygen may also be used as an oxidant either instead of air or with air to reduce ignition temperatures. Further, electrical energy can be passed through the fuel conduit, raising the temperature of the conduit to a temperature above which the fuel will ignite when combined with the oxidant.

Disclosed are, inter alia, methods of forming coated substrates for use in catalytic converters, as well as washcoat compositions and methods suitable for using in preparation of the coated substrates, and the coated substrates formed thereby. The catalytic material is prepared by a plasma-based method, yielding catalytic material with a lower tendency to migrate on support at high temperatures, and thus less prone to catalyst aging after prolonged use. Also disclosed are catalytic converters using the coated substrates, which have favorable properties as compared to catalytic converters using catalysts deposited on substrates using solution chemistry. Also disclosed are exhaust treatment systems, and vehicles, such as diesel vehicles, particularly light-duty diesel vehicles, using catalytic converters and exhaust treatment systems using the coated substrates.

A catalyst for purifying the exhaust gases of diesel engines, which catalyst contains at least one zeolite and, additionally, at least one of the support oxides aluminum oxide, silicon dioxide, titanium dioxide and aluminum silicate and at least one of the noble metals platinum, palladium, rhodium and iridium. In this catalyst the atoms of the noble metals have a mean oxidation number of less than +2.5, on average more than 3 metal ligands and less than 3 oxygen ligands and are present on the zeolites and support oxides in the form of crystallites having a mean particle size of from 1 to 6 nm.

The invention discloses a method for coating micro/nano-metal powder by chemical vapor deposition, including: decomposing difluorocarbene precursor gas via a cracking pipe to generate difluorocarbene free radicals; contacting the generated difluorocarbene free radicals with micro/nano-metal powder, and due to polymerization between difluorocarbene free radicals, a compact polytetrafluoroethylene coating film is generated on the surface of micro/nano-metal powder. In allusion to disadvantages and defects of the application of micro/nano-metal powder in energy-containing materials, polytetrafluoroethylene is polymerized on the surface of metal powder by chemical vapor deposition in order to coat micro/nano-metal powder. In the invention, the ignition temperature of metal powder is effectively decreased, the ignition delay time is shortened, and the combustion speed of metal powder is improved; the surface of metal powder coated with polytetrafluoroethylene is highly hydrophobic, so that reactive metal powder can be effectively prevented from absorption of moisture and oxidation.

The invention provides a boiler coal combustion-improving desulfurizing and denitrifying agent composition. The composition comprises the following raw materials in parts by weight: 2-7 parts of sodium carbonate, 1-3 parts of alumina, 2-8 parts of aluminium hydroxide, 2-5 parts of ferric trichloride, 2-6 parts of ferric oxide, 3-10 parts of potassium permanganate, 3-10 parts of potassium chlorate, 10-35 parts of activated attapulgite clay, 15-30 parts of urea, 2-4 parts of ammonium formate, 2-4 parts of ammonium chloride, 6-23 parts of ammonium acetate, 3-9 parts of manganese oxide, 9-12 parts of copper chloride, 1-3 parts of copper oxide, 2-4 parts of zinc sulfate, 1-3 parts of zinc nitrate, 7-18 parts of potassium dichromate, 1.0-1.5 parts of titanium dioxide, 0.5-1.0 part of barium molybdate, 0.5-1.5 parts of cobalt sulfate, 0.5-1.5 parts of vanadium pentoxide, 0.3-0.7 part of cerium oxide, 0.1-0.2 part of sodium dodecyl benzene sulfonate and 0.1-0.2 part of alkyl glyceryl ether. The composition is convenient to use, has stable properties, plays roles of combustion improving, desulfurization and denitrification, has coal saving rate of 8-25% and can remove fixed sulfur by 50-70%.

The catalyst for eliminating HCN-containing waste gas is prepared via dissolving H2PtCl6.6H2O in H2O, impregnating Al2O3 carrier in H2PtCl.6H2O solution, drying calcinating and reduction. When it is used, the catalyst is loaded in reactor furnace, the temperature in the furnace is raised to 250-450 deg.c mixed gas contg. HCN, NH3, tar and air is introduced into the reactor furnace to eliminate waste gas via catalytic burning. The present invention has the advantages of simple preparation process, low cost and simple operation.

Disclosed are, inter alia, methods of forming coated substrates for use in catalytic converters, as well as washcoat compositions and methods suitable for using in preparation of the coated substrates, and the coated substrates formed thereby, which in some cases use iron-exchanged zeolite particles that provide enhanced performance such as lower light-off temperatures and lower pollutant levels in exhaust gases. The catalytic material is prepared by a plasma-based method, yielding catalytic material with a lower tendency to migrate on support at high temperatures, and thus less prone to catalyst aging after prolonged use. Also disclosed are catalytic converters using the coated substrates, which have favorable properties as compared to catalytic converters using catalysts deposited on substrates using solution chemistry. Also disclosed are exhaust treatment systems, and vehicles, such as diesel vehicles, particularly light-duty diesel vehicles, using catalytic converters and exhaust treatment systems using the coated substrates.

A Diesel engine anti-wear lubricant oil additive composition that includes organo-metallic compounds of Cu, Ce, etc., is used to catalytically bum-off diesel particulate matter (PM) collected by diesel particulate filter (DPF). A fuel borne catalyst (FBC) of Cu,Ce,Fe etc., required for regenerating the DPF is made by blending a predetermined quantity of used engine oil, removed from the engine crankcase oil system, with fuel in the fuel tank of a diesel engine equipped with DPF and EGR systems. A method of fumigating water and catalytic compounds of Cu, Fe, Ce, etc., into the air-intake system of a diesel engine in the EGR gases from the DPF or air, to reduce both PM and NOx emissions from a diesel engine, with improved engine lubrication performance, is also disclosed.

The invention disclosed herein relates to an explosive capable of enhanced combustion efficiently capable of sustaining a high pressure over a period of time in a confined environment, such as an air tight room or a cave, where oxygen may be in limited supply. An embodiment of the present invention is a metal composite that combines a binder, a reactive metal and an oxidizer. In another embodiment, a plasticizer and a catalyst are added. In another embodiment of the present invention, a solid fuel-air explosive (SFAE) having an annular construction is used. In a typical annular construction, a cylindrical shell of SFAE surrounds the cylindrically shaped high explosive. The SFAE includes at least one of reactive metal and metal composite. In addition, the metal composite is formed from at least one reactive metal, at least one binder and an oxidizer.

The invention provides a catalyst for tail gas purification and a preparation method of the catalyst for tail gas purification. The catalyst for tail gas purification comprises an alumina supporter, cerium dioxide borne on alumina and a precious metal active component borne on the surface of the cerium dioxide. The alumina supporter and the cerium dioxide are prepared according to the sediment hydrothermal method. The precious metal active component is borne according to the hydrothermal in-situ reduction sediment method. According to the catalyst for tail gas purification, the interaction between the cerium dioxide and a precious metal species is strong, the cerium dioxide supporter can generate more oxygen vacancies, oxygen molecules are activated and converted into a reactive oxygen species, and therefore the activity of catalytic oxidation is improved. Interspersion and mutual contact are conducted between the alumina and the cerium dioxide, the mutual insulation function is achieved, sintering with the single cerium oxide serving as a supporter can be avoided, and the thermal stability of the alumina at a high temperature is remarkably improved.

The invention relates to the field of internal combustion engine tail gas treatment, in particular to a ternary catalyst for purifying the tail gas of an internal combustion engine and a preparation method thereof. The preparation method is characterized in that cordierite ceramic honeycomb is used as a carrier, precious metals such as platinum, palladium and rhodium are adopted as active components, the bottom layer catalyst contains the palladium active component with the active component concentration of 0.1 to 6g/L, the content of cerium of a cerium-containing oxygen storage material is 15-30 percent by weight, the top catalyst contains palladium and/or rhodium active component with the concentration of 0.01 to 0.6g/L, the content of cerium of the cerium-containing oxygen storage material is 40 to 80 percent by weight, a heat-resisting oxide is aluminum oxide consisting of gamma-aluminum oxide or theta-aluminum oxide, the aluminum oxide is stabilized by 3 to 8 percent by weight of lanthanum, the specific surface area is 120 to 300 m<2>/g, the weight ratio of the aluminum oxide to cerium-containing oxygen storage material to additive is 100: (40-80): (11-30). By adopting the catalyst based on the technical scheme, the conversion efficiency of the pollutants in tail gas of the internal combustion engine is high, the ignition temperature is lower, and the thermal stability in high temperature is high.

The invention provides a dual-layer noble metal active component catalyst, wherein the active component is distributed in lamination, and a dual-layer coating method is adopted to separate the active components of noble metal and lead the active components to stay on different layers to play individual functions fully. Not only the resistance to aging at high temperature of catalyst can be satisfied but also the catalytic reduction ability of nitrogen oxide under lean-burn condition can be improved and the ignition temperature of the catalyst can be reduced, thus greatly improving the utilization of active component.

The conversion of NO_x to nitrogen in the exhaust of a lean burn engine using a hydrocarbon assisted-selective catalytic reduction system is benefited by a two-stage oxidation catalyst-reduction catalyst SCR reactor. The character and quantity of the oxidation catalyst is managed to just activate the hydrocarbon reductant at low temperatures (but not fully burn it at high temperatures) to increase its NO_x reduction efficiency as the exhaust then contacts the larger reduction catalyst stage of the two-stage reactor.

The invention discloses a gas water heater. The gas water heater comprises a pre-mixing cavity shell, a combustor, a heat exchanger, a pre-heating disc and controller; a mixing cavity is limited in the pre-mixing cavity shell, and the pre-mixing cavity shell is provided with a gas inlet, an air inlet and a mixed gas outlet which are communicated with the mixing cavity; the combustor is communicated with the mixed gas outlet, and a catalyst for catalyzing the combustor to carry out smokeless catalytic combustion is arranged in the combustor; the heat exchanger is connected with the combustor so as to absorb heat generated by combusting of the combustor and is provided with a water inlet and a water outlet; the pre-heating disc is connected with the combustor so as to preheat the combustor; and the controller is connected with the pre-heating disc so as to control heating temperature of the pre-heating disc. According to the gas water heater, the reaction rate of fuel can be improved, the utilization rate of the fuel is improved, generation of harmful gas can be avoided, the fuel can be subject to flameless catalytic combustion in the combustor, generation of the harmful gas is greatly reduced, and use is safe and environment-friendly.

The skin friction drag acting on a surface of an article travelling at high speed such as a vehicle at supersonic or particularly hypersonic speed can be reduced by introducing a fuel into the boundary layer under conditions of the fuel introduction to ensure combustion in the boundary layer. The fuel is injected through orifice(s) or a slot provided at the surface so that the fuel enters the passing fluid with a major component of the direction of injection being parallel to the local flow direction. The fuel is injected at supersonic speed, e.g. at a speed of about Mach 1.5 or higher. The invention is applicable to scramjet engines with the fuel being injected around the entire internal circumference of the wall of the scramjet engine, upstream of the commencement of the combustion chamber.

The invention discloses a preparation method of a composite metal oxide catalyst for the catalytic decomposition of VOCs (Volatile Organic Compounds). Nano powder TiO2 is used as a carrier; after a composite metal oxide layer is formed, transition metal salt is added; the composite metal oxide catalyst with multiple active components is formed after heat treatment. The composite metal oxide catalyst has higher catalytic oxidation capacity (more than 98 percent) for ester and benzene organic matters at a low ignition temperature (300 DEG C). The catalyst is prepared by adopting a normal-temperature precipitation method; the method is simple and convenient. The composite metal oxide catalyst does not contain a noble metal element, and is low in cost. The composite metal oxide catalyst is prepared by adopting a two-step precipitation method to ensure that Ce is closely in contact with the TiO2; a solid solution is conveniently formed during roasting; the composite metal oxide catalyst has favorable oxygen supply capacity. Finally, loaded transition metal elements are uniformly distributed on the surface of the catalyst; the adsorption on molecules of the VOCs is facilitated; an active site is provided; the catalytic capacity is increased. The obtained catalyst is used for oxidizing the VOCs into CO2 and H2O, has advantages of high catalytic conversion rate, low ignition temperature, high stability, low price and the like, and has favorable application value and prospect.

The invention provides a low-temperature plasma no-heat ignition flame stabilization device which adopts the low-temperature plasma to cause the flammable mixed gas to produce a plurality of free radicals and active components such as electrons and hydroniums, etc. to implement large-volume igniting flammable mixed gas, belonging to aeronautics and astronautics power thrust system field. The invention consists of a high pressure powers supply 1, a high pressure electrode 2, an air inlet hole 3, an air inlet seat 4, a retaining medium 5, a low voltage electrode 6, a rectifier 7 and a combustion chamber 8; the high voltage electrode 2 is hermetically connected with the air inlet seat 4 and is connected with a high voltage electrode 1; the air inlet hole 3 is provided with openings on the air inlet seat 4; the interior of the air inlet seat 4 is hermetically connected with the retaining medium 5; the external wall of the rectifier 7 is tightly close to the internal wall of the retaining medium 5; the upstream is the high voltage electrode 1 and the downstream is the combustion room 8 which is hermetically connected with the retaining medium 5. The invention can implement large-volume ignition, reduces the voltage amplitude to large extent, has simple structure and reliable system, and is an ignition device with extremely developmental prospect used by the aeronautics and astronautics and industrial combustion systems.

The invention discloses an aluminum powder surface self-activation method. The method includes steps: adding aluminum powder into an anhydrous solvent, mixing, and stirring to disperse uniformly to form aluminum powder dispersion liquid; dissolving organic fluoride into a solvent to form organic fluorine solution, adding the organic fluorine solution into the aluminum powder dispersion liquid by acertain rate, and stirring to volatilize the solvent in which the organic fluoride is dissolved at a certain temperature, so that organic fluoride is slowly separated out by crystallization on the aluminum powder surface to form a compact surface activation layer; centrifugally separating to remove the solvent, washing, and performing vacuum drying at 60 DEG C to obtain organic fluorine surface self-activated aluminum powder. By forming of the organic fluorine self-activation layer on the aluminum powder surface, the aluminum powder ignition temperature can be effectively lowered while ignition delay time is shortened, combustion efficiency of aluminum powder in oxidants is improved while the energy releasing rate is increased, and the organic fluorine surface activation layer is effective in aluminum powder oxidation, so that stability is improved.