186results about How to "Promote catalysis" patented technology

Improved catalysts useful in a number of organic synthesis reactions such as olefin metathesis and atom or group transfer reactions are made by bringing into contact a multi-coordinated metal complex comprising a multidentate Schiff base ligand, and one or more other ligands, with an acid under conditions such that said acid is able to at least partly cleave a bond between the metal and the multidentate Schiff base ligand of said metal complex, optionally through intermediate protonation of said Schiff base ligand.

The invention discloses a titanium silicalite TS-1 catalyst preparation method. Cheap inorganic Titanium silicalite is used as raw material, low quantity of tetrapropylammonium hydroxide or tetrapropylammonium bromide is adopted as template agent, and inorganic alkali such as ammonia water is used as alkali source so that the raw materials for preparation have low price and the production cost isgreatly reduced. The precursor preparation process is simple and easy to control, seed crystal is added to reduce the crystallization time and the repeatability is good. As secondary crystallization is adopted, the non-framework titanium is further reduced, and the acid site of the molecular sieve is reduced, the grain size is controllable within certain range, the molecular sieve channel becomessmoother to facilitate direct membrane separation of micrometer crystalline grains, and the obtained Titanium silicalite TS-1 catalyst has large grains, high activity, stable catalytic performance and broad industrial application prospect.

The invention relates to the field of materials and analytical chemistry, and particularly relates to a noble-metal nanoparticle-loading metal-organic framework composite material, a preparation method and application. The preparation method of the metal-organic framework composite material loading two or more than two noble-metal nanoparticles, provided by the invention, comprises the following steps: mixing raw materials containing organic metal ligands, metal ions and one, two or more than two kinds of first noble-metal nanoparticles, then, putting the mixture in a reaction still or microwave oven, and carrying out a reaction, so as to obtain a metal-organic framework loading one, two or more than two kinds of first noble-metal nanoparticles; mixing the metal-organic framework loading the first noble-metal nanoparticles, a precursor solution of second noble-metal nanoparticles and a reducer, thereby obtaining the metal-organic framework composite material. The composite material hasthe characteristics of high specific surface area, high porosity and easiness in surface functionalization, meanwhile, has the electric conductivity and catalytic effect of the noble-metal nanoparticles, and can be applied to an electrochemiluminescence system.

A method for operating a broadband lambda sensor for determining the concentration of oxygen in the exhaust gas of an internal combustion engine operated with a fuel-air mixture is provided. In this method, a pump voltage (UP) is applied to the pump cell of the sensor, this voltage-being set dependent on a Nernst voltage (UN) tapped at the Nernst cell, and, dependent on the oxygen content of the exhaust gas, driving a cathodic or anodic pump current IP via the pump cell. In order to maintain the measurement sensitivity of the sensor even during secondary fuel injection in lean operation and / or in “fast light off” operation, the polarity of the pump voltage (UP) is repeatedly reversed during the duration of a secondary fuel injection and / or of the “fast light off” operation, so that an anodic pump current briefly arises that pumps oxygen ions into the measurement chamber, occupied by the measurement electrode of the Nernst cell and the inner electrode of the pump cell, in which chamber the oxygen ions oxidize the hydrocarbons.

The present invention relates to a process for the treatment of at least one of the electrodes (cathode and / or anode) of a fuel cell, before the said cell is operated, and before or after the said electrode is placed in the said cell, comprising the step consisting in forming a biofilm on at least part of the surface of the said electrode, by immersing the said electrode in a medium capable of causing the growth of biofilms, the said biofilm being intended to catalyse the reaction at the electrode, and the step consisting simultaneously in subjecting the said electrode to a polarization potential. The invention also relates to a fuel cell comprising at least one electrode covered with a biofilm, obtained before the said electrode is placed in the cell, and to the electrode.

The invention provides an exhaust gas purifying apparatus comprising a NOx storage reduction catalyst and a particulate filter, wherein the original NOx storage ability of the NOx storage reduction catalyst is sufficiently utilized. Specifically, the exhaust gas purifying apparatus comprises a filter (40) arranged in the upstream of a NOx storage reduction catalyst (22), a fuel supply means (42) for supplying a fuel so that the fuel is mixed with the exhaust gas flowing into the filter (40), and an ozone supply means (30) for supplying ozone in the downstream of the filter (40) so that ozone is mixed with the exhaust gas flowing into the NOx storage reduction catalyst (22).

The invention discloses a method for preparing a coating with a micro-nano composite structure through liquid plasma spraying. The method comprises the following steps of (1) adding solution salt and suspension liquid granules into a solvent to obtain a suspension liquid; and (2) delivering the suspension liquid to a flame flow generated by a plasma spraying gun through a non-atomizing nozzle, and praying the flame flow generated by the plasma spraying gun to a pretreated spraying matrix, thereby obtaining the costing with the composite structure on the spraying matrix. By using the method, the problems of coating performance reduction and invalidation caused by grain growth in a thermal barrier coating, a solid oxide fuel battery electrode coating, an air-sensitive coating of a medium-high temperature gas sensor and a high-temperature wear-resistant lubricating coating can be solved or partially solved.

The invention discloses an acrylic acid synthesis method. The method is characterized by directly synthesizing acrylic acid by using CO2 and ethylene as raw materials, acetonitrile as a solvent and a metal Ru complex as a catalyst, wherein the mole ratio of ethylene to carbon dioxide is (1 to 1)-(1 to 5), preferably (1 to 2)-(1 to 4); the reaction temperature is 40-130 DEG C, preferably 50-120 DEG C; the reaction pressure is 0.5-6.0MPa, preferably 1.0-5.5MPa. In the method, acrylic acid is directly synthesized by using CO2 and ethylene as the raw materials. The method has the advantages of low reaction temperature, high product yield, and the like.

The invention relates to a nitrated carbon fiber loaded bismuth oxyhalide nanoflower and a preparation method of the nanoflower. The preparation method of the nanoflower comprises the following steps: respectively dissolving a halogenous ionic solution and bismuth nitrate in ethylene glycol monomethyl ether, slowly adding the halogenous ionic solution into a bismuth nitrate solution after the halogenous ionic solution and the bismuth nitrate are fully dissolved in the ethylene glycol monomethyl ether, evenly stirring and mixing the mixed solution, pouring the mixed solution to a high-pressure reaction kettle with a polytetrafluoroethylene liner, then placing nitrated carbon fiber in the kettle, reacting for 0.5-6 hours in a drying oven at the temperature of 150-160 DEG C, naturally cooling and then washing and drying to obtain a product. Through the nitrated carbon fiber loaded bismuth oxyhalide nanoflower, the BiOX is reused and the problem of secondary pollution is solved; ACF (Active Carbon Fiber) is excellent in adsorption property and capable of absorbing organic pollutants and facilitating the photo-catalysis.

The invention provides a cryptomelane-based composite metal element catalyst, and a preparation method and application thereof. The cryptomelane-based composite metal element catalyst is prepared from acryptomelane-containing manganese oxide molecular sieve and a doping metal element, wherein the doping metal element enters a cryptomelane type manganese oxidemolecular sieve framework; the mole ratio of the manganese element in the cryptomelane type manganese oxidemolecular sieve to the doping metal element is (100 to 1) to (10 to 1); the cryptomelane type manganese oxide molecular sieve is obtained through the reaction of septivalence manganese and bivalent manganese; the mole ratio of the septivalence manganese to the bivalent manganese is (2 to 1) to (0.5 to 1). The cryptomelane-based composite metal element catalyst provided by the invention has high catalytic activity, and the usage of precious metal is not needed or reduced, so that the cost of the catalyst is greatly reduced; the catalyst has no need to be activated by utilizing hydrogen reduction, is simple in usage conditions, and can be widely applied in purification treatment of benzene-containing waste gas discharged by fixed sources such as a smelting plant, an oil refinery plant and a chemical plant.

The invention discloses an acrylate synthesis method. The method is characterized by directly synthesizing acrylate under the action of a methylation reagent by using CO2 and ethylene as raw materials, acetonitrile as a solvent and a metal Mo complex as a catalyst, wherein the mole ratio of the raw material ethylene to carbon dioxide is (1 to 1)-(1 to 5), preferably (1 to 2)-(1 to 4); the gas flow rate is 1-20ml / min, preferably 3-15ml / min; the reaction temperature is minus 5-50 DEG C, preferably 0-40 DEG C; the reaction pressure is 0.01-0.5MPa, preferably 0.05-0.4MPa. In the method, acrylate is directly synthesized under the action of the methylation reagent by using CO2 and ethylene as the raw materials. The method has the advantages of low reaction temperature, high product yield, and the like.

The invention discloses a pollution-free paddy rice planting method. The method comprises the following steps: A, planting milk vetch as green manure in a rice field, and applying a basic manure, wherein 500-800 kg of the basic manure is applied to each mu of the rice field; B, after the rice field is subjected to exposure, performing rotary tillage, ridge separation, irrigation and rice transplanting; C, applying a compound fertilizer to seedlings after the seedlings are inserted; D, grazing 8-15 7-10-day-old ducks to each mu of the rice field after 15-20 days of rice transplanting, evicting the ducks from the rice field after 25-40 days, spraying a biological pesticide, draining for 7-10 days, topdressing 30-100 kg of the compound fertilizer used in the step C to each mu of the rice field, irrigating till the depth of water is 8-10 cm, grazing 5-10 7-10-day-old ducks to each mu of the rice field again, and evicting the ducks from the rice field before 15-20 days of rice mature. According to the pollution-free paddy rice planting method, the yield is high, pollution is avoided, produced rice tastes good, and meanwhile, high-quality duck is obtained.

Composite combustion catalyst particles are described and disclosed. A metal core of a combustible metal can be coated with a metal oxide coating. Additionally, a catalyst coating can at least partially surround the metal oxide coating to form a composite catalyst particle. The composite catalyst particles can be dispersed in a variety of fuels such as propulsion fuels and the like to form an enhanced fuel. During initial stages of combustion, the catalyst coating acts to increase combustion of the fuel. As combustion proceeds, the metal core heats sufficiently to disturb the metal oxide coating. The metal core then combusts in highly exothermic reactions with an oxidizer and the catalyst coating to provide improved energy densities to the enhanced fuel. Enhanced fuels using these composite combustion catalyst particles can exhibit decreased ignition delay times and increased energy densities sufficient for use in high performance propulsion applications such as pulse detonation engines, scramjets, and ramjets.

The invention discloses a planting method for organic high-yield rice. The method comprises: planting broad beans in a rice field, after harvesting the broad beans, performing green manure dressing and retting, and applying base fertilizer; performing water-controlling harden-seedling on rice seedlings whose seedling age is 15-20 days for 2-3 days; performing rotary tillage, ridge dividing, irrigation on the rice field, and then transplanting rice seedlings; after the rice seedlings survive, dressing a compound fertilizer to promote rice seedling tiller; 13-18 days after rice transplanting, putting newly-hatched ducklings whose day-age is 12-20 in the rice field according to amount of 8-15 per mu, 25-40 days after putting the ducks in the rice field, driving the ducks out of the rice field, spraying biopesticide, performing field draining for 7-10 days, topdressing a nitrogen-phosphorus-potassium composite fertilizer according to amount of 20-50 kg per mu, and then irrigating to 8-10 cm, and driving the ducks in the rice field, 15-20 days before the rice is mature, taking back the ducks, and cutting off water and drying the field. The planting method for organic high-yield rice is high in yield, and obtained rice is good in quality, and high-quality duck meat is obtained.

The invention discloses a carbon nitride-supported molybdenum nitride nanoparticle photocatalyst, and a preparation method and an application thereof. The preparation method comprises the steps: firstly, preparing ultra-thin precursors of CN and Mo2N, and then preparing a Mo2N aqueous solution and a CN ethanol dispersion solution; and then dropping the CN ethanol dispersion solution into the Mo2Naqueous solution in a 70 DEG C oil bath, stirring and mixing, then centrifuging, washing and drying to obtain the carbon nitride-supported molybdenum nitride nanoparticle photocatalyst. The photocatalyst has the advantages of wide light absorption range, property of high decomposition of water to produce hydrogen, low electrical resistivity, fast current carrier transfer ability, high photogenerated current carrier separation ability, low current carrier recombination rate, good hydrogen evolution circulation stability and the like, is used for photocatalytic decomposition of water to producehydrogen, and has the highest hydrogen production rate reaching 0.89 [mu]mol.g<-1>.h<-1>. The preparation method has the advantages of simple operation, low cost and non-toxic used raw materials, andconforms to production of the concept of environmental protection.

The invention relates to a method for preparing a porous magnetic and catalytic double-functional one-dimensional composite material. The method comprises the following steps of: (1) dissolving Zn(Ac)2.2H2O, Fe(NO3)3.9H2O and AgNO3 in distilled water and absolute ethanol, stirring by using magnetic force at room temperature for 1 to 3 hours until the added components are fully dissolved to obtain a solution a, slowing adding polyvinylpyrrolidone into the absolute ethanol, stirring by using the magnetic force for 1 to 3 hours until the polyvinylpyrrolidone is completely dissolved to form a transparent solution b, slowly adding the solution b into the solution a, continuously stirring by using the magnetic force for 1 to 3 hours, and thus obtaining a yellow viscous solution c; and (2) spinning by using the solution c through an electrostatic spinning instrument to obtain a one-dimensional fiber, drying the obtained fiber in a drying oven at the temperature of between 50 and 70 DEG C for 10 to 14 hours, calcinating the obtained fiber under different atmospheres, and thus obtaining the porous magnetic and catalytic double-functional one-dimensional composite material. Compared with the prior art, the method has the advantages of controllable components and crystal forms, high purity, convenience for treatment and the like and is easy to industrialize.

The invention provides a preparation method of porous carbon-supported nitrogen-containing bimetallic catalyst and application of the porous carbon-supported nitrogen-containing bimetallic catalyst inthe aspect of electrochemical reduction of nitrate in water. The preparation method of the catalyst comprises the following steps: sequentially adding copper nitrate trihydrate, triethylene diamine,a terephthalic acid solution and a precursor solution containing noble metal Pd or Pt into DMF; then dispersing the porous carbon carrier in the mixed solution and moving to a hydrothermal kettle forheating reaction to obtain a solid material; roasting the obtained solid material to obtain a porous carbon-supported nitrogen-containing bimetallic catalyst; the catalyst is coated on an electrode sheet to prepare a working electrode module, and the nitrate in water is reduced by electrocatalysis. The nitrogen-containing bimetallic catalyst obtained by the preparation method of porous carbon-supported nitrogen-containing bimetallic catalyst and electrochemical application thereof has high activity and high nitrogen selectivity for the electrochemical reduction of nitrate, and has higher removal efficiency under the condition that the pH value of a water body is neutral; the porous carbon carrier plays a role of dispersing active components and shows good stability.

The invention addressed two critical issues in fuel processing for fuel cell application, i.e. catalyst cost and operating stability. The existing state-of-the-art fuel reforming catalyst uses Rh and platinum supported over refractory oxide which add significant cost to the fuel cell system. Supported metals agglomerate under elevated temperature during reforming and decrease the catalyst activity. The catalyst is a perovskite oxide or a Ruddlesden-Popper type oxide containing rare-earth elements, catalytically active firs row transition metal elements, and stabilizing elements, such that the catalyst is a single phase in high temperature oxidizing conditions and maintains a primarily perovskite or Ruddlesden-Popper structure under high temperature reducing conditions. The catalyst can also contain alkaline earth dopants, which enhance the catalytic activity of the catalyst, but do not compromise the stability of the perovskite structure.

The invention relates to a manganese oxide catalyst as well as a preparation method and application of the manganese oxide catalyst. The preparation method comprises the steps: dissolving a manganesesource or a mixture of the manganese source and a composite metal source, adding urea, stirring, heating and precipitating the solution, and then, carrying out solid-liquid separation; and washing theobtained solid phase, drying the solid phase, and then, roasting the solid phase to obtain the manganese oxide catalyst. The manganese oxide catalyst is prepared by taking urea as a precipitant and using a uniform coprecipitation method; the obtained catalyst has the advantages such as high selectivity, high activity, high stability, low ignition temperature and long service life when being usedfor catalytic combustion of ethyl acetate; and compared with an existing noble metal catalyst, the manganese oxide catalyst is higher in catalytic activity, lower in catalysis temperature range, widein material source, simple in preparation process, high in economic benefit and wide in application prospect.

The invention discloses a preparation method of a silica-supported magnetic cobalt oxide catalyst. The preparation method of the silica-supported magnetic cobalt oxide catalyst sequentially comprises the following steps: respectively dissolving CoCl2, FeCl2 and FeCl3 in water to prepare solutions with the concentration of 1-2mol / L, mixing two solutions, dropwise adding a certain amount of NaOH, carrying out reaction and aging to form hydrotalcite-like precipitate of a layered structure, precipitating, separating and washing; adding solids obtained during precipitating into sodium silicate solution, stirring, precipitating, separating, and calcining the obtained solids at the temperature of 300-350 DEG C, so that the silica-supported magnetic cobalt oxide catalyst is obtained. Due to supporting of silica, hydrotalcite-like slice layers are separated from one another and are fixed, so that the silica-supported magnetic cobalt oxide catalyst has a good porous structure and large specific surface area, and adsorption and catalysis can be facilitated; and magnetic particles exist, so that the silica-supported magnetic cobalt oxide catalyst can be quickly separated after degrading pollutants in wastewater.

The invention discloses a preparation method of an iron oxide nanosheet. The method sequentially comprises the steps of: placing 500mL of a FeCl2 solution in waterbath at a constant temperature of 70-80DEG C, adding 2-4mL of 30% (mass fraction) hydrogen peroxide and a certain amount of a NaOH dilute solution dropwise into the solution at the same time, maintaining a pH value of 12-13, carrying out reaction for 2-3h, then transferring the product into an autoclave, performing heating to 150-180DEG C within 1h, further carrying out reaction for 4-8h, and conducting natural cooling to room temperature to form precipitate with a stratified structure, carrying out precipitation separation, and performing washing with deionized water 2-3 times; adding the solid obtained by precipitation into a sodium lactate solution with a concentration of 2-4mol / L in a solid-liquid ratio of 1:10-1:50, then performing stirring for 4-5h, and conducting precipitation separation, washing the obtained solid with deionized water 2-3 times, then performing calcination at 400-450DEG C to remove lactate therein, thus obtaining the iron oxide nanosheet. The structure is conducive to adsorbing and catalyzing pollutants.

The invention discloses a magnetic supported catalyst, which is a complex of a nano magnetic particle surface grafted polyvinyl imidazol ligand and metal ions. A molar ratio of imidazol groups to the metal ions in the complex is (0.5-300):1; and the polyvinyl imidazol ligand is homopolymer of N-polyvinyl imidazol monomers or copolymer of N-polyvinyl imidazol monomers and one or more types of water-soluble monomers. The catalyst has high catalytic efficiency, and can be separated from a reaction medium by applying a magnetic field, so that the catalyst is recycled, and solves the problem that the conventional catalyst has low catalytic efficiency of preparing polyphenyleneoxide (PPO) in a reaction medium, particularly in an aqueous medium, and is difficult to recycle. The invention also discloses a preparation method and application of the magnetic supported catalyst. The preparation method is easy to operate and control, and is suitable for industrial production.

The present invention discloses a direct methanol fuel cell anode catalyst, in particular to a platinum-based compound catalyst; the basic structure is Pt-WO 3. The method of preparing the catalyst is as follows: mixed sol of H 2 SO 4, H 2 PtCl 6 and Na 2 WO 4 with a certain concentration is electrodeposited by positioning a certain electric potential on a carbon material to prepare the platinum-based compound catalyst with the basic structure: Pt-WO3. The catalyst of the invention improves activity of catalyzing methanol to oxide and has good stability; the doping of auxiliary catalyst WO3 improves the utility ratio of Pt; the invention also improves the catalytic activity of catalyzing CH3OH to oxide; the method of depositing and preparing catalyst is simple in technique, convenient in operation and easy in control; the catalyst can be electrodeposited in the condition of room temperature, thereby the preparation cost of the catalyst is low.

The invention belongs to the field of sulfur recovery, and particularly relates to an SWSR-8 pressurization sulfur recovery process. The process comprises the steps that acid gas enters a sulfur making furnace, H2S is subjected to a high-temperature Claus reaction and converted into sulfur, and sulfur enters a two-stage converter to conduct two stage catalytic conversion for recovering sulfur; sulfur making tail gas enters a hydrogenation reactor, under the action of a hydrogenation catalyst, SO2 and COS are reduced to H2S through hydrogenation hydrolysis, reduced H2S gas is absorbed with an MDEA solution, and after purified tail gas recovers heat through incineration, flue gas is exhausted to the atmosphere through a chimney, wherein the pressure of acid gas entering the sulfur making furnace ranges from 90 kPa(g) to 120 kPa(g), and the pressure of the sulfur making furnace ranges from 90m kPa(g) to 120 kPa(g). The pressure of cooling and heat exchange equipment such as a sulfur making waste heat furnace, a first stage sulfur condenser, a second stage sulfur condenser, a third stage sulfur condenser, a steam generator and a tail gas waste heat boiler is higher than that in the prior art, the total heat transfer coefficient is increased, the occupied area is decreased, catalytic and absorption reactions can be conducted conveniently, the sulfur recovery rate is increased, and SO2 discharge is reduced.

The invention relates to a fuel oil additive, in particular to a fuel oil additive which can be added into gasoline and diesel. The fuel oil additive consists of the following raw materials by weight percentage: 2 to 3 percent of octanol, 10 to 13 percent of isopropyl alcohol, 1.5 to 3.5 percent of nitrobenzene, 1.5 to 3.5 percent of methenamine, 0.3 to 0.5 percent of ferrocene, and the rest is methyl alcohol. The fuel oil additive of the invention adopts the liquid phase catalysis technology to promote the catalysis and cracking of the fuel oil, and enhance the physical activity, thereby causing the combustion to be more full, even and thorough. The fuel oil additive of the invention has the following functions of: 1. saving the fuel oil; 2. eliminating carbon in exhaust gases; and 3. reducing exhaust gas discharge to satisfy the European III standard.

The invention discloses an in-situ carbon-coated copper-nickel alloy material photocatalyst and a preparation method and an application thereof. The preparation method comprises the steps: firstly, acopper-nickel bimetallic organic framework (CuNiBTC) is prepared through a hydrothermal method, and a CuNiBTC material is obtained through centrifugation, washing and drying; and vacuum sealing is carried out on a sample by using a quartz tube, and calcining is carried out at high temperature to obtain the in-situ carbon-coated copper-nickel alloy nanoparticle photocatalyst. The in-situ carbon-coated copper-nickel alloy nanoparticle photocatalyst has the advantages of wide light absorption range, high carbon dioxide reduction performance, low electrical resistivity, rapid carrier transfer capability, high photon-generated carrier separation capability, low carrier recombination rate and good carbon dioxide conversion cycle stability, is used for near-infrared light catalytic reduction of carbon dioxide, and has the carbon monoxide precipitation rate up to 11.205 [mu]mol*g<-1>*h<-1>. The preparation method is simple to operate and low in cost, the used raw materials are non-toxic, and the product has a certain economic value and conforms to production of the environmental protection concept.

The invention discloses Co-Fe-B amorphous alloy catalyst and its preparation. The mole ratios of the components are: Co: 0-32%, Fe: 0.1-32%, B: 67-70%. The catalyst of the invention passes X-ray diffraction and selective-area electronic diffraction tests, and has apparent non-crystal structure and 19-71m2 / g surface area. The catalyst is utilized to acetonitrile election hydro-preparation of ethamine. The method has simple operation and the good catalyzing and active selection to the reactions of hydro-furfural, hydro-dextrose and cinnamaldehyde.

The invention relates to a molecular sieve nanotube aerogel as well as a preparation method thereof and belongs to the technical field of the preparation of a molecular sieve. The inner diameter of the molecular sieve nanotubes is adjustable within a range of 50nm to 100nm and the outer diameter of the molecular sieve nanotubes is adjustable within the range of 170nm to 400nm. The molecular sieve nanotubes are symbiotically built of molecular sieve nanocrystals and have firm and stable structure; and the nanotubes are crosslinked and communicated to form a network skeleton. A macropore of which the diameter is 1-20mu m is defined by the crosslinked molecular sieve nanotubes, the molecular sieve nanotubes have the same structural characteristics as micropore-mesopore-macropore-nanotubes. The different macroscopical morphologies of the molecular sieve nanotubes, such as zero dimensional particle, two-dimensional films, and three-dimensional block can be self-formed and have a very low density of 0.15-0.25g / cm3 and a high porosity of 85-95%. The preparation method disclosed by the invention is applied to silica-alumina and heteroatom silica-alumina molecular sieves, such as Silicalite-1, ZSM-5, TS-1, X, Y and A.

The invention discloses a preparation method and application of a superparamagnetic Fe3O4 nano material, and relates to the technical field of nano materials. The preparation method comprises the following steps: dissolving solid FeCl3.6H2O into distilled water, stirring under room temperature, and fully dissolving, thus obtaining a solution a; slowly adding triethanolamine (TEA) into the solution a, continuously stirring, thus obtaining a brown red solution b, adjusting the pH value of the solution b by ammonia water or solid NaOH, thus obtaining a dark brown solution c, putting the solution c under a closed state for hydrothermal synthesis, and finally taking out a product by a magnetic separation method. The superparamagnetic Fe3O4 nano material prepared by the preparation method disclosed by the invehtion is better in water solubility, good in biocompatibility, high in adsorption performance and excellent in catalysis and magnetic property, can be applied to the fields such as magnetic resonance imaging, data storage, medicament and gene targeting, cell separation and sewage treatment, and has a wider application prospect.

Apparatus for reactivating a sulfur poisoned oxidation catalyst operating in exhaust of a lean burn, methane source fueled combustion device. Reactivation includes desulfation of the poisoned catalyst through a CO supplementation apparatus communicating with the control unit that is adapted to supplement CO content in exhaust reaching the catalyst, while avoiding an overall rich exhaust atmosphere at the catalyst (e.g., an added supply of hydrocarbons to one or more-of the lean burn engine's combustion chambers as by an ECU controlled extra supply of NG to some of the combustion chambers). Also featured is a method for desulfation of an oxidation catalyst of a lean burn CNG engine by supplying excess CO to exhaust reaching the catalyst while retaining an overall lean state, and a method of assembling an apparatus for reactivating a sulfur deactivated lean burn NG engine catalyst by assembling a CO supplementation apparatus with control unit.