231 results about "Ammoxidation" patented technology

The invention discloses an amorphous PtNi self-supporting catalytic electrode, a preparation method thereof and a direct ammonia fuel cell, and belongs to the technical field of electrode materials. According to the technical scheme, the catalytic electrode adopts foamed nickel as a conductive framework substrate, and an amorphous PtNi alloy wall-shaped array structure grows on the foamed nickel in situ; the preparation method of the catalytic electrode comprises the following steps: pretreating the foamed nickel substrate; the preparation method comprises the following steps: adding platinum diacetylacetonate, potassium hydroxide, N, N-dimethylformamide and diethylenetriamine into ethylene glycol to prepare a precursor solution; and immersing foamed nickel into the precursor solution, and carrying out in-situ growth reaction under high-temperature and high-pressure conditions to obtain the amorphous PtNi self-supporting catalytic electrode. The catalytic electrode has the beneficial effects that the catalytic electrode shows high specific activity and extremely low apparent activation energy in ammoxidation reaction, still keeps 90% of current density after continuously working for 1000 hours, and shows excellent long-term stability and durability.

This invention discloses a composite sponge carrier for anaerobic ammonia oxidation, its preparation method, and its application, belonging to the field of wastewater treatment technology. The composite sponge carrier comprises: a porous polyurethane sponge and a composite component loaded on the surface and internal pores of the porous polyurethane sponge; wherein the composite component includes chitosan-modified biochar as a microbial affinity functional component and zeolite powder as a component for ammonia nitrogen adsorption and ion exchange regulation. This invention introduces more active functional groups and hydrophilic interfaces conducive to microbial attachment through chitosan modification, and then co-impregnates and loads it with zeolite powder onto the surface and pores of the polyurethane sponge. This improves the composite sponge carrier's retention and enrichment capacity for anaerobic ammonia oxidizing bacteria, improves the local substrate environment during the start-up phase, promotes rapid biofilm establishment, and enhances the system's operational stability.

The present invention discloses an ammonia oxidation process and a method for recovering Rh from a gas phase comprising volatile precious metals, comprising the steps of: a) generating or providing volatile precious metals, particularly by operating a catalytic system comprising a catalyst, wherein the catalyst contains precious metals, wherein the precious metals at least comprise Rh, wherein the volatile precious metals comprise at least volatile Rh; b) contacting volatile Rh generated in step a) with a recovery system comprising a compound of formula Co3-xMxO4, where M is Fe or Al and x = 0-2; and c) forming a solid composition comprising the compound of formula Co3-xMxO4 and Rh, wherein the compound of formula Co3-xMxO4 is bonded with Rh, particularly as determined by SEM-EDS and TEM analysis. The present invention further relates to the use of the compound of formula Co3-xMxO4, where M is Fe or Al and x = 0-2, or the use of the recovery system, for recovering at least volatile Rh.

The application provides an ammonia oxidation catalyst, a preparation method and application thereof, and a method for synthesizing acrylonitrile by propylene ammonia oxidation, and the general formula of the active component of the catalyst is Mo 12 Bi a B b C c D d O x ; wherein B is selected from at least one of group VIII metal elements; C is selected from at least one of alkaline earth metal elements; D is selected from at least one of alkali metal elements; and the hollow rate of the catalyst is 0-5%. The catalyst has the advantages of good sphericity, few hollow particles, uniform particle size distribution, good fluidization state in a fluidized bed reactor, less catalyst loss after long-term operation, high acrylonitrile yield, low content of by-products two-carbon and propylene aldehyde, and better long-term operation stability.

The present application provides a catalyst for preparing acrylonitrile, which comprises a carrier and an active component, wherein the active component is a metal oxide having the general formula (I) A a B b C c Fe d Ni e Bi f Mo 12 O x (I). The present application also provides a method for preparing the catalyst for preparing acrylonitrile of the present application. The present application also provides the use of the catalyst for preparing acrylonitrile of the present application or the catalyst for preparing acrylonitrile prepared according to the method of the present application in the preparation of acrylonitrile by propylene ammoxidation. The catalyst for preparing acrylonitrile of the present application still has a high acrylonitrile yield under a high propylene load. The catalyst not only has a high acrylonitrile yield under a high propylene load, but also has a low acrolein yield, so that the acrylonitrile recovery rate of the device is high to improve the production efficiency and economic benefit of the device.

The application provides a method for synthesizing adiponitrile by selective ammoxidation of epoxycyclohexane. The purpose of the application is to simulate and optimize the process of synthesizing adiponitrile by one-step direct ammoxidation of epoxycyclohexane, and to develop a new type of multiphase composite metal vanadium-based oxide catalyst, which is composed of Co a V b P c Mo d MNOx / TiO2, the active elements of which include vanadium element V, cobalt element Co, phosphorus element P and molybdenum element Mo, M is an auxiliary metal element (Mn, Cr, Fe or Ni), N is an alkali metal (Na, K or Cs); the value range of a is 0.2-1.2; the value range of b is 0.8-1.5; the value range of c is 0.1-0.23; the value range of d is 0.07-0.35; x is the proportion of oxygen atoms required to meet the oxidation state of metal. The catalyst has the advantages of simple preparation, good cycle stability, high yield and the like. The yield and product purity of adiponitrile are improved, the energy consumption in the production process of adiponitrile is reduced, and a breakthrough is realized in the production technology of adiponitrile.

A burner basket assembly of an ammonia oxidation reactor, wherein the burner basket assembly comprises a burner basket inner side wall, a gas-permeable bottom plate, wherein between the burner basket inner side wall and the bottom plate a circumferential radial clearance is present, an L-shaped clearance cover profile which comprises a horizontal clearance cover plate and a vertical clearance cover plate which has a certain length, wherein the horizontal and the vertical clearance cover plate are mechanically fixed to each other, and wherein the L-shaped cover profile during operation is displaceable in a vertical direction in view of the burner basket inner side wall, a support ring which is mechanically fixed to the burner basket inner side wall, an upside-down positioned L-shaped locking profile, comprising a horizontal locking plate and a vertical locking plate which are mechanically fixed to each other, wherein the horizontal locking plate is mechanically fixed to the support ring, wherein the L-shaped locking profile, the support ring and the respective part of the burner basket inner side wall limit a ring-shaped gap into which at least a top part of the vertical clearance cover plate is located, and wherein between the support ring and the vertical clearance cover plate a distance is arranged which is such that the vertical displacement of the vertical clearance cover plate in view of the burner basket inner side wall is limited by the support ring and at all times during the operation of the burner basket, collision between the L-shaped clearance cover profile and the L-shaped locking profile is avoided.

The invention discloses a preparation method of a superfine PtIr nanowire catalyst for ammoxidation. The preparation method comprises the following steps: firstly, fully dissolving platinum acetylacetonate, iridium acetylacetonate, tungsten hexacarbonyl and dodecyl trimethyl ammonium bromide in oleylamine to obtain a light yellow solution; carrying out ultrasonic treatment on the obtained light yellow solution until the solution is fully dissolved; and heating the obtained uniform light yellow solution to 190 DEG C in an oil bath, keeping the temperature for 5 hours, centrifuging, washing and drying to obtain the superfine PtIr nanowire catalyst. The nanowire structure has a high specific surface area and abundant active sites, and is beneficial to effective quality and electron transmission. Through alloying of Ir and Pt, the electronic structure on the surface of the catalyst is changed, and the poisoning probability is effectively reduced. Meanwhile, the adsorption and activation process of ammonia molecules is optimized through the synergistic effect between Pt and Ir, the reaction activation energy is reduced, and the reaction rate is remarkably increased. The catalyst not only has remarkable ammonia oxidation catalytic performance, but also is good in stability and simple in preparation process.

The invention belongs to the technical field of sewage treatment, and particularly relates to a lateral flow anaerobic ammonia oxidation effluent deep nitrogen and phosphorus resource recycling method which comprises the following steps: mixing treated anaerobic sludge digestion liquid and untreated anaerobic sludge digestion liquid in an intermediate water tank to form mixed inlet water; adding a magnesium source into the mixed inlet water in the middle water tank to form a middle mixed solution; transferring the intermediate mixed solution into a short-cut denitrification-anaerobic ammonia oxidation coupled struvite reactor, adjusting the pH value of the intermediate mixed solution, and adding a carbon source into the pH-adjusted intermediate mixed solution to form a reaction solution; and carrying out solid-liquid separation on a product obtained after the reaction of the reaction liquid, and discharging the separated liquid or systematically recycling the separated liquid. According to the invention, deep nitrogen removal and phosphorus resource recovery under the condition of low carbon source can be realized, and a new way is provided for subsequent deep treatment of a short-cut nitrification-anaerobic ammonia oxidation process.

Provided are a catalyst for an ammoxidation reaction, a method for producing the catalyst for an ammoxidation reaction, and a method for ammoxidation.

A catalytic article for treating an exhaust stream, which comprises -a substrate, -a coating layer, comprising a first catalyst containing a precious metal component and a second catalyst containing a molecular sieve component, in a first coating configuration; or -a substrate, -a first coating layer, which comprises a first catalyst containing a precious metal component, and -a second coating layer, which covers at least part of the first coating layer and comprises a second catalyst containing a molecular sieve component, in a second coating configuration; wherein the coating layer in the first coating configuration or the second coating layer in the second coating configuration has inter-particle pores at a pore ratio of 5.7% or more respectively. It also relates to a process for preparing the catalytic article by using a pore-forming agent in the slurry for depositing a coaing layer, and to a system for treating an exhaust stream comprising the catalytic article.

The utility model provides an anaerobic ammonia oxidation reaction system. The reaction system comprises a wastewater treatment system, the wastewater treatment system comprises: a first reactor for removing nitrate nitrogen in wastewater and producing first treated water; the second reactor is used for removing ammonia nitrogen and nitrite nitrogen in the first treated water and producing second treated water; the third reactor is used for adjusting the nitrogen composition and concentration of the second treated water and producing third treated water; and the fourth reactor is used for reducing nitrate nitrogen in the third treated water into nitrogen so as to reduce the concentration of total nitrogen in the effluent. The utility model solves the technical problems that an anaerobic ammonia oxidation water treatment system adopting a traditional activated sludge process is insufficient in total nitrogen treatment capacity during operation, and particularly cannot effectively remove nitrate nitrogen in an anaerobic ammonia oxidation reaction product; in the prior art, the treated water can still contain a certain amount of nitrogen pollutants and cannot meet the requirements of discharged water quality.

A device and a method for maintaining the stability of anaerobic ammonium oxidation (anammox) by using a combined zeolite filler to resist water quality fluctuations are provided. The device includes a water inlet tank, an anammox reactor, and a water outlet tank, where the anammox reactor is filled with the combined zeolite filler maintained in a state of suspension, domestic sewage enters the anammox reactor through a water inlet pump, and effluent water enters the water outlet tank through an overflow port. The device combines the physical characteristics of zeolite adsorption of ammonium with the anammox process: when the concentration of ammonium in the influent water is too high, the zeolites will temporarily store the excess ammonium adsorbed; when the concentration of nitrite in the influent water is too high, the zeolites are capable to release the stored ammonium into a liquid phase through balanced adsorption desorption.

The application provides a method for one-step conversion of aromatic alcohol into aromatic nitrile, which comprises the following steps: using a metal salt as a catalyst, a hydroxylamine salt as an ammonia source, air or oxygen as an oxidant, and performing an ammoxidation reaction of the aromatic alcohol under light conditions to convert the aromatic alcohol into the aromatic nitrile in one step. The application does not use any expensive or toxic photocatalyst, material or reagent, the raw material is easy to obtain, the operation is simple, the reaction is carried out at normal temperature and pressure, the conditions are mild, and the application has an industrial amplification prospect; and the safety, environmental protection, economy and social benefit of the application have remarkable advantages.

The invention discloses a starting and control method for treating ammonia-nitrogen wastewater by an integrated complete ammoxidation coupling short-cut denitrification anaerobic ammoxidation process, and belongs to the field of wastewater biological treatment. The starting method adopts a step-by-step inoculation strategy, and comprises the following steps: firstly, inoculating complete ammoxidation sludge in the SBR reactor for low-oxygen domestication, and after successful starting, supplementing and inoculating short-cut denitrification coupled anaerobic ammoxidation sludge. The control method adopts a sectional water inlet mode, and comprises the following steps: a first part of ammonia nitrogen wastewater firstly enters an integrated SBR (Sequencing Batch Reactor), and ammonia nitrogen is directly oxidized into nitrate nitrogen through complete ammonia oxidizing bacteria (Comammox) under the condition of low dissolved oxygen; aeration is stopped, a carbon source is added for short-cut denitrification, and nitrate nitrogen is reduced into nitrite nitrogen; and then pumping a second part of ammonia nitrogen wastewater, and converting ammonia nitrogen in the wastewater and accumulated nitrite nitrogen into nitrogen by using anaerobic ammonium oxidation bacteria, so as to remove the ammonia nitrogen in the wastewater. According to the invention, deep denitrification is realized under the condition of saving energy consumption and a carbon source.

The invention belongs to the technical field of material chemistry, and particularly relates to an MOF catalyst containing high-valence copper and a preparation method and application of the MOF catalyst. According to the invention, Ag is doped on a Cu-based metal organic framework material framework through an ion exchange method, then the Ag is mixed with a binder solution to prepare slurry, the slurry is coated on an electrode substrate, the electrode substrate is dried to serve as a working electrode, constant potential or circulating potential is applied to the working electrode in a preset voltage range in an electrochemical system containing an electrolyte, and thus the Cu-based metal organic framework material is obtained. Cu (III) is generated in situ through electrochemical reconstruction, and the MOF catalyst containing high-valence copper is obtained. The MOF catalyst containing high-valence copper has excellent ammoxidation reaction activity and stability, is especially suitable for high-conversion-rate and high-selectivity ammoxidation reaction to prepare nitrite, and is suitable for industrial induced production application.

The invention relates to the technical field of wastewater treatment, and particularly provides a method for improving the anaerobic ammonia oxidation denitrification effect of high-ammonia-nitrogen wastewater. The method is realized by adding one or more enhancer combinations into a reaction system, wherein the enhancer is selected from vitamin B6, siderophore catechin (CAT) and siderophore hydroxyethyl ethylenediamine triacetic acid (HEDTA). By adding the enhancer, the inhibition effect of a high-ammonia-nitrogen environment on anaerobic ammonium oxidation functional flora can be effectively relieved, and the metabolic activity and the proliferation rate of the anaerobic ammonium oxidation flora are remarkably enhanced. The method is simple and convenient to operate and low in cost, can greatly improve the denitrification efficiency and operation stability of the system under high ammonia nitrogen load on the premise of not changing the structure of the existing reaction system, and is suitable for treating high ammonia nitrogen wastewater such as mine leaching tail water, landfill leachate and the like.

The present invention relates to a composition comprising platinum supported on titanium oxide, the platinum particles having an average particle diameter of 50-200 nm. The composition has a surprisingly low light-off temperature for the ammonia oxidation and a high selectivity for oxidation to N2.

The invention discloses a collaborative deep purification method and system for phenol-cyanamide in coking wastewater, and belongs to the technical field of industrial wastewater treatment. According to the invention, a quality-based grading and recycling coupled system is adopted, and oil-water separation and soluble tar reduction are simultaneously realized through front-stage pretreatment, so that the subsequent treatment load is effectively reduced; catalytic oxidation and ozone oxidation are synergistically enhanced in the middle section, so that favorable conditions are created for biochemical treatment; the biochemical section is used for constructing a poison-resistant flora and coupling a short-cut nitrification and denitrification or anaerobic ammonia oxidation process to realize low-carbon denitrification; at the tail end, through the synergistic effect of membrane separation and selective adsorption, the water quality of recycled water is guaranteed, and meanwhile resource recycling of ammonia nitrogen is achieved.

The invention belongs to the technical field of catalysts, and particularly provides a supported acrylonitrile catalyst and a preparation method thereof, the acrylonitrile catalyst comprises the following raw materials by weight: 50-60 parts of an active component, 6-10 parts of a rare earth precursor, 50-65 parts of a MnO2 / SiO2 composite carrier, 18-28 parts of a cosolvent, and 160-200 parts of deionized water. The acrylonitrile catalyst provided by the invention can be used in a production process of a propylene ammoxidation method, and has the advantages of high acrylonitrile yield, low acraldehyde yield and good mechanical strength.

This invention discloses a two-dimensional layered ammonia oxidation catalyst based on MXene, its preparation method, and its application in low-temperature ammonia fuel cells. The catalyst comprises an active component and a support. The active component is one or two of the transition metals Pt, Ir, and Pd, and the support is accordion-shaped MXenes. The catalyst support prepared by this invention has a large specific surface area, in which the transition metal nanoparticles are uniformly dispersed and have strong interactions with the MXenes, which can significantly improve its ammonia electrocatalytic oxidation activity, showing good application prospects in ammonia fuel cells.

The present invention describes a method for producing precious metal meshes for ammonia oxidation. The method according to the invention allows for the robust and simple production of distortion-free meshes through a special winding process.

The present application relates to the technical field of ammonia oxidation catalyst, in particular to a transition metal-based ammonia oxidation catalyst and a preparation method and application thereof.The present application provides a transition metal-based ammonia oxidation catalyst, the ammonia oxidation catalyst comprises a carrier and an active component, the structural formula of the carrier is Ce a Sb b O2;wherein a=0.8-0.95, b=0.05-0.2.The transition metal-based ammonia oxidation catalyst provided by the present application can reach 80-100% ammonia conversion rate under the condition of 200-300 DEG C, and when copper is used as the active component, the nitrogen selectivity can reach more than 55% under the condition of 150-300 DEG C.

The embodiment of the application provides a kind of propane ammoxidation preparation acrylonitrile, it is related to acrylonitrile generation technical field;The method comprises: propane, ammonia and oxygen are mixed, and mixed gas is obtained;The mixed gas occurs ammoxidation under the action of metal oxide composite catalyst, and acrylonitrile is obtained;The metal oxide composite catalyst includes Mo-V base metal oxide, and also includes alkali metal or alkaline earth metal.The method of the present application has relatively mild reaction conditions, the yield can basically reach more than 60%, the selectivity can reach more than 80%, improves the raw material utilization rate, reduces energy consumption and equipment investment, thereby effectively reducing the production cost of acrylonitrile.At the same time, the process of the present application can effectively control the side reaction in the reaction process, reduce the generation of by-products, and reduce the difficulty of subsequent separation and purification of reaction products.

The present application relates to a kind of ammonia oxidation catalyst and its preparation method and application, the catalyst includes outer layer structure, intermediate layer structure and inner layer structure, wherein, outer layer structure includes Mo, V, Co, optional metal Bi and metal A, wherein the metal A is selected from one or more of Cs, K, Cu;Intermediate layer structure includes Mo, Cr, optional Sb, optional W and element X, wherein metal X is selected from one or more of Fe, P, Na, Mg;Inner layer structure includes Mo, Al, Si and optional element Y, element Y is selected from one or more of Sb, Sr, Ru, B, Ce.The catalyst has the characteristics of high activity, high thermal conductivity, which is applied to the reaction process of gaseous ammonia oxidation hydrocarbon or alcohol to prepare nitrile compound, and the catalyst has good stability, long service life, and high selectivity, high yield.

The application discloses a catalyst for preparing acrylonitrile through propylene ammoxidation and a preparation method and application thereof. An active component of the catalyst comprises La, Q and R, R is at least one of Ce, Pr, Nd, Sm and Eu elements, and Q is at least one of Zr, Ca, Ti and P elements; an atomic ratio of the La to the R is 0.05-0.45, and an atomic ratio of the Q / (La+R) is 0.01-0.25. When the catalyst is used for preparing acrylonitrile through propylene ammoxidation, the catalyst has the characteristics of high activity and low two-carbon yield in a long-period running process.

The application provides an ammonia oxidation expanded granular sludge bed reactor and a sewage treatment method thereof, and belongs to the technical field of biological denitrification of sewage. The reactor comprises a reactor main body, a reagent adding box connected with the reactor main body, a clean water temporary storage tank, a membrane assembly and a high-pressure gas cylinder connected with the membrane assembly. The reactor is based on a nitrite-dependent anaerobic methane oxidation process. The reactor is inoculated with n-DAMO bacteria after enrichment culture. The n-DAMO bacteria, methane and nitrite are used to realize the ammonia oxidation process in wastewater. The energy and resource consumption in the traditional ammonia oxidation process is greatly saved, the global warming problem caused by greenhouse gas emission is solved, and the implementation of the new ammonia oxidation process is possible.

The present invention discloses an ammonia oxidation catalyst, a preparation method thereof, and a method for producing nitrile compounds. The catalyst of the present invention has an XRD diffraction peak at 2θ = 27 ± 0.3° as X, and an XRD diffraction peak at 2θ = 28 ± 0.3° as Y, with the intensity ratio of X to Y satisfying 0 ≤ X / Y ≤ 1.1. The catalyst is prepared from raw materials including a support and an active component, wherein the support includes silicon dioxide and a support additive, wherein the support additive is an inorganic base. The catalyst of the present invention is used to produce nitrile compounds, achieving high raw material conversion and high selectivity for nitrile compound products.

The present invention relates to a vehicle-mounted ammonia cracking hydrogen generation system for an ammonia engine and a thermal management method therefor. The system comprises a liquid ammonia storage tank, a liquid ammonia gasification preheating tank, a hydrogen generation line, a cracking gas storage line, an ammonia hydrogen inlet channel premixing pipe, an ammonia oxidation plant heat generation line, an air supply line, and an end gas supply line.The heat from the ammonia oxidation plant heat generation line not only provides heat for cracking ammonia, but also preheats the ammonia required for cracking; the ammonia required by the ammonia oxidation plant heat generation line is preheated, and the heat, along with the exhaust gas heat from an engine, is supplied to an aftertreatment system; the molar ratio of the supplied ammonia to that of the air is adjusted according to the engine's operating conditions to modify the heat release from the ammonia oxidation plant heat generation line, and the reaction is carried out according to the most suitable reaction equation, thus avoiding the generation of exhaust gas pollutants; furthermore, the heat is distributed and managed with the ammonia oxidation plant heat generation line as its core.