651 results about "Rhodium" patented technology

The invention provides a method and system for detecting the content of platinum, palladium and rhodium in an automobile exhaust purification catalyst and application, and relates to the technical field of automobile exhaust purification, the method comprises the following steps: crushing, grinding, sieving, performing microwave acidolysis, neutralizing, washing and drying a catalyst sample to obtain dry filter residues; a trapping agent and a fluxing agent are added into the dry filter residues, constant-temperature heating is conducted in inert gas, then cooling forming is conducted, and an alloy button is obtained; blowing ash on the alloy, then adding mixed acid into the alloy, heating the alloy in a water bath at 95 DEG C for 25-35 minutes to obtain a dissolved solution, then adding a masking agent into the dissolved solution, and oscillating to obtain a solution to be detected; and filtering the liquid to be detected, fixing the volume and detecting. According to the method, precise quantification of trace platinum, palladium and rhodium in the complex matrix catalyst can be realized, and the method has a relatively high recovery rate; meanwhile, pollution elements are prevented from being used, and the method is green and efficient and better conforms to the concept of green chemistry.

The present invention relates to the field of catalyst technology, discloses a supported noble metal catalyst and its preparation method and application, the catalyst includes a first carrier and a coating loaded on the first carrier, the raw material composition for preparing the coating includes a second carrier, an active component precursor, an auxiliary agent precursor, a binder and a dispersant; the first carrier is cordierite, mullite or cordierite-mullite; the second carrier is titanium dioxide and / or aluminum oxide; the active component precursor is selected from at least one of a platinum precursor, a palladium precursor and a rhodium precursor; the auxiliary agent precursor is a combination of a cerium precursor, a zirconium precursor and a neodymium precursor; the binder is a mixture of an organic binder, an inorganic binder and a coupling agent. The supported noble metal catalyst has low production cost, high catalytic activity, strong anti-poisoning ability and long service life, can be used for the removal of volatile organic compounds, and is particularly suitable for the removal of flue gases such as ethylene and propane with large air volume and low concentration of organic small molecule hydrocarbons.

The invention relates to a method for purifying rhodium from a complex-component rhodium leaching solution, and belongs to the technical field of precious metal refining and purification. The method comprises the following steps: adding a reducing agent into rhodium leaching liquid for reduction to obtain RhCl3 primary purification liquid and insoluble slag; simultaneously adding sulfite and ammonium salt into the RhCl3 primary purification liquid to precipitate rhodium in the form of (NH4) 3Rh (SO3) 3; hydrochloric acid is added into the (NH4) 3Rh (SO3) 3 precipitation residues, heating and boiling are conducted, the (NH4) 3Rh (SO3) 3 precipitation residues are dissolved in the form of RhCl3 and enter a solution, SO3 < 2-> in the solution is removed in the form of SO2, and a secondary purification solution of RhCl3 is obtained; adding a strong oxidant into the secondary purified solution of RhCl3, and carrying out oxidation reaction to obtain RhCl4; adding alkali into the RhCl4 solution to adjust the pH value, and boiling to obtain RhO2. 2H2O precipitation slag; and the RhO2. 2H2O precipitation slag is sequentially subjected to pure water slurrying, hydrazine hydrate reduction, calcination and hydrogen reduction to obtain the high-purity metal rhodium. According to the method disclosed by the invention, the high-purity metal rhodium of which the purity is greater than 99.95% can be prepared, and the direct recovery rate of rhodium is greater than 97%.

To provide a calcined body that is processed easier than a conventional calcined body and where differences in hardness between production lots are suppressed.SOLUTION: A calcined body comprises: at least one first transition metal element selected from the group consisting of manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), molybdenum (Mo), technetium (Tc), ruthenium (Ru), rhodium (Rh), palladium (Pd), and silver (Ag); a coloring element of at least one of a lanthanoid rare earth element and a second transition metal element different in kind from the first transition metal element; and zirconia containing a stabilizing element. A content of the first transition metal element is 100 mass.ppm or more, a content of the second transition metal element is less than 100 mass.ppm, and an absolute value of a difference in hardness relative to a hardness of a calcined body obtained from a commercially available powder is 10 HV or less.SELECTED DRAWING: None

A method may include operating a dehydrogenation process whereby a hydrocarbon-containing feed is converted to light olefins, wherein the dehydrogenation process utilizes a fluidized process catalyst that circulates between a reactor and a combustor. The method may comprise withdrawing the process catalyst from the dehydrogenation process, modifying the process catalyst to form a modified catalyst, and adding the modified catalyst back to the dehydrogenation process. The process catalyst may include from 0.1 wt. % to 10 wt. % of one or more metals chosen from gallium, indium, thallium, or combinations thereof, from 1 ppmw to 1000 ppmw of one or more metals chosen from platinum, palladium, rhodium, iridium, ruthenium, osmium, or combinations thereof, and at least 85 wt. % support. Modifying the process catalyst may include adding one or more of manganese, iron, chromium, or vanadium.

The invention provides a method for recovering platinum group metal from a waste automobile exhaust purification catalyst, and belongs to the field of precious metal recovery. The method comprises the following steps: carrying out crushing and impurity removal pretreatment on the waste catalyst to obtain solid residues; mixing the obtained solid slag with alkali liquor, and performing hot-pressing activation to obtain active slag; leaching the active slag by using an acid leaching system of hydrochloric acid-hydrogen peroxide-sodium chloride to obtain a leaching solution enriched with platinum group metals; adjusting the acidity of the leachate, adding a first adsorption material, selectively adsorbing platinum and palladium, and separating supernate and a platinum / palladium enrichment material; adjusting the acidity of the supernate, adding a second adsorption material, selectively adsorbing rhodium, carrying out solid-liquid separation, and collecting a rhodium enrichment material; respectively eluting and refining the platinum / palladium enrichment material and the rhodium enrichment material, and recovering platinum, palladium and rhodium; through the optimally designed recovery method of alkaline hot-pressing activation-mild acidic directional leaching-two-stage magnetic adsorption separation, efficient recovery of platinum, palladium and rhodium in the waste automobile exhaust catalyst is realized.

The invention discloses a catalyst for dealkylation in a chlorine-containing environment as well as a preparation method and application of the catalyst, and belongs to the technical field of catalyst reaction. The catalyst comprises a carrier and an active component, wherein the carrier comprises ZrO2 and MgFeO4; the active component comprises an auxiliary agent and a noble metal component, the auxiliary agent comprises a V2O5-WO3 composite oxide and a CeO2-MnO2 composite oxide, and the noble metal component comprises at least three of rhodium, ruthenium, platinum, palladium and gold. The noble metal components grow in mesopores of the carrier in a confined manner, and the auxiliaries with dechlorination and catalytic oxidation functions are uniformly distributed on the surface of the carrier, so that a two-step catalytic strategy of dechlorination and oxidation of chlorine-containing waste gas is realized, the poisoning phenomenon of the catalyst is effectively avoided, and an excellent catalytic effect is formed. Moreover, the catalyst is stable in property, still keeps an excellent catalytic function after being used for a long time, and is higher in practicability and better in economical efficiency.

According to the microwave reactor and method for recycling the three-way catalytic precious metal, through the synergistic effect of microwave radiation and the telescopic glass stirring rod, the problem that the mass transfer efficiency is low due to high viscosity of a traditional ionic liquid leaching system is solved, the precious metal leaching time is shortened, and the efficiency is improved. Meanwhile, a diamond ATR crystal infrared probe is adopted to monitor components of a reaction solution in real time, multi-parameter linkage control of microwave power, temperature and stirring rate is combined, reaction conditions are dynamically optimized, and the recovery rate of platinum, palladium and rhodium is increased. The method systematically solves the technical bottlenecks of high energy consumption, heavy pollution and low ionic liquid leaching efficiency of the traditional pyrogenic process / wet process, and provides an innovative scheme with high efficiency, low environmental load and industrial feasibility for precious metal recovery.

The invention relates to the field of preparation of nano materials, in particular to a preparation method of a metal-oxide cluster electro-catalytic material based on an ammonia-mediated electrostatic adsorption principle, and aims to solve the problem that a metal-oxide cluster heterogeneous interface is difficult to accurately construct by an existing method. The preparation method comprises the following steps: dispersing a carbon carrier, a soluble inorganic compound containing platinum, ruthenium and rhodium, a soluble metal complex anion salt and dopamine hydrochloride in a water-alcohol mixed solution, adding ammonia water, and preparing a metal-oxide heterogeneous cluster precursor through an ammonia-mediated electrostatic adsorption effect; and pyrolyzing the precursor in a reducing atmosphere to prepare the metal-oxide cluster electro-catalytic material. The prepared electro-catalytic material has a definite heterogeneous cluster interface and has excellent performance in alkaline hydroxide reaction. The method is simple and convenient to operate, low in cost and low in energy consumption, can be popularized to various metal-oxide cluster electro-catalytic materials, and has application potential.

The invention relates to a catalyst for preparing 1, 4-cyclohexanedimethanol (CHDM) by catalyzing dimethyl terephthalate (DMT) hydrogenation and a preparation method thereof, non-noble metals nickel (Ni) and copper (Cu) are used as active components, silicon dioxide is used as a carrier, ammonia water in a solution is evaporated out after ammonia water precipitation, and a catalyst sample is obtained. The active components mainly adopt metal Ni and Cu elements with relatively low price, compared with noble metals such as ruthenium, rhodium, platinum and the like, the use cost of the catalyst is greatly reduced, the bimetallic catalyst Ni-Cu-SiO2 is prepared by an ammonia distillation method, 1, 4-cyclohexanedimethanol can be prepared by catalyzing dimethyl terephthalate hydrogenation by a one-pot method, and the catalyst has a wide application prospect. The preparation cost of the catalyst is relatively low, the dispersity and stability of the catalyst are improved by adopting an ammonia distillation method, the CHDM is prepared by adopting a one-pot method, the energy consumption is further reduced, the reaction procedure is simplified, and the preparation method is simple and is easy to amplify to industrial production.

The present invention discloses a gas-phase preparation method of 1,1,1,4,4,4-hexafluoro-2-butyne. Using a mixture of 2,3-dichloro-1,1,1,4,4,4-hexafluoro-2-butene and hydrogen as raw materials, under the action of a particulate catalyst, 1,1,1,4,4,4-hexafluoro-2-butyne is obtained through a one-step hydrodechlorination reaction. The catalyst includes a carbon carrier and an active phase in the form of hollow spheres supported on the carbon carrier. The active phase includes: a first metal selected from at least one of silver, copper, nickel, and cobalt; and a second metal selected from at least one of palladium, platinum, and rhodium. The present invention has the advantages of high product selectivity, high catalytic activity, obtaining the reaction product through a one-step reaction, and being suitable for industrial application, etc.

A method may include contacting a hydrocarbon-containing feed with a catalyst in a reactor to form an olefin-containing effluent, then at least partially separating the olefin-containing effluent from the catalyst. Passing the catalyst to a combustor and heating the catalyst by combusting a supplemental fuel. The supplemental fuel includes methane in an amount greater than or equal to 1 mol. %. Passing the catalyst from the combustor to the reactor, such that at least a portion of the catalyst continuously cycles between the reactor and the combustor. The catalyst includes from 0.1 wt. % to 10 wt. % of one or more metals chosen from gallium, indium, thallium or combinations thereof, from 5 ppmw to 1000 ppmw of one or more metals chosen from platinum, palladium, rhodium, iridium, ruthenium, osmium, or combinations thereof, from 100 ppmw to 30000 ppmw of chromium, and at least 85 wt. % support.

The invention provides a method for recovering rhodium in organic residual liquid containing triphenylphosphine / phosphine oxide, and relates to the technical field of precious metal recovery, and the method comprises the following steps: S1, carrying out reduced pressure rectification on the organic residual liquid containing triphenylphosphine / phosphine oxide to remove volatile components until the indexes of the residual liquid meet the feeding requirements of a subsequent process, and collecting light components for independent storage; s2, adding an acidic medium into the organic phase after light component removal, stirring and heating, introducing an oxidizing agent to carry out oxidation-complexation reaction, maintaining reaction conditions until the reaction is complete, standing for phase splitting, and collecting a water phase containing rhodium complex ions; according to the method, a core process combining oxidation-chlorination transfer and anion exchange adsorption is adopted, and key parameters of each process are accurately controlled, so that the rhodium recovery rate is stabilized at 95% or above, the rhodium content in the residual liquid can be reduced to 5 ppm or below, the industrial emission standard is completely met, and compared with the prior art, the resource recovery efficiency is greatly improved, and the cost is reduced. And waste of precious metal resources is effectively reduced.

Discloses a hydrometallurgical process and system for the recovery of precious metals; specifically palladium, rhodium, and platinum metals, at high purity and with limited waste and environmental fouling.

The invention discloses a high-dispersion rhodium-loaded defect-state black titanium dioxide photocatalyst, preparation and application thereof in preparation of propylene through photocatalytic methane conversion, and belongs to the technical field of methane photocatalytic conversion. The preparation method comprises the following steps: firstly, carrying out chemical reduction treatment on titanium dioxide, carrying out high-temperature calcination, and then washing, carrying out suction filtration and drying to obtain black titanium dioxide; carrying out hydrogen peroxide treatment on the titanium dioxide, and further modifying the surface structure of the titanium dioxide to obtain defect-state black titanium dioxide; and finally, mixing with a metal Rh precursor solution, and calcining to obtain the high-dispersion metal Rh loaded defect-state black titanium dioxide photocatalyst. The prepared catalyst has excellent light absorption capacity, energy from visible light to a near-infrared region (accounting for about 96% of solar energy) in sunlight can be fully utilized, efficient and selective conversion from methane to propylene is achieved under the conditions of low temperature and visible light irradiation, the propylene selectivity can reach 70% or above, and reaction activity far exceeding thermodynamic limitation is shown.

The invention provides a composite hydrogen transfer catalyst based on an MOFs material as well as a preparation method and application of the composite hydrogen transfer catalyst. The composite hydrogen transfer catalyst comprises the MOFs material loaded with an active metal component and solid alkali, the active metal component is selected from at least one of palladium, platinum, ruthenium, rhodium and nickel; the active metal component accounts for 0.5-5% of the mass of the catalyst; the MOFs material is selected from at least one of ZIF-8, MIL-101, UiO-66, HKUST-1 and MOF-5 (Metal Organic Frameworks); the solid alkali is selected from at least one of magnesium oxide, calcium oxide, hydroxyapatite and barium oxide. The catalyst provided by the invention has the advantages of high catalytic activity, good selectivity, strong stability, reusability and the like, can efficiently catalyze fatty alcohol to perform hydrogen transfer reaction under a lower-temperature reaction condition to prepare Guerbet alcohol, remarkably improves the yield and purity of a product, and reduces the reaction energy consumption and cost.

The invention relates to the technical field of precious metal recovery and purification, in particular to a metal rhodium recovery and purification method which comprises the following steps: S1, adjusting the pH value of rhodium leaching liquid, heating, adding a reducing agent, and filtering after reaction to obtain primary impurity removal liquid; s2, controlling the pH value of the primary impurity removal liquid to be 1.5-2, heating, adding thiodiglycolic acid and ammonium salt, reacting, and performing solid-liquid separation to obtain primary rhodium-containing precipitate; s3, dispersing the primary rhodium-containing precipitate in an acid solution, adding a strong oxidant, carrying out heating reflux, and adjusting the pH value to 6-7 to obtain a secondary rhodium-containing precipitate; s4, dispersing the secondary rhodium-containing precipitate in a solution with a pH value of 13-14 for pulpifying, adding a reducing agent, carrying out a reduction reaction at 90-100 DEG C, and carrying out solid-liquid separation to obtain a tertiary rhodium-containing precipitate; s5, calcining the third rhodium-containing precipitate, and performing hydrogen reduction to obtain metal rhodium; the method has the advantages that the recovery efficiency of rhodium can be improved, and the pressure on the environment is reduced.

A method for decorating a timepiece component, particularly a skeleton type watch dial. The component includes at least two different visual appearances, each visual appearance being the unique combination of a surface finish and of a colour. The decoration has the following steps: i) providing a component blank with a first unfinished surface (10a); ii) creating on said first unfinished surface a first termination possessing a first surface finish; iii) applying to the first termination one or more layers of atoms so as to give the first termination a first colour; iv) creating a second termination having at least one breaking of a corner on the blank in order to form at least one bevel or at least one chamfer having a second unfinished surface; v) creating on said second unfinished surface a second termination conferring a second surface finish, and vi) using electroplating, PVD or ALD, to deposit a metallic layer, preferably a layer of rhodium or of gold, on the second termination so as to give the second termination a second colour.

An exhaust gas purification catalyst (10) contains a refractory three-dimensional structure (20), a second catalyst layer (31) containing palladium and rhodium, and a first catalyst layer (32) containing palladium positioned between the refractory three-dimensional structure (20) and the second catalyst layer (31), in which the first catalyst layer (32) or the second catalyst layer (31) further contains a Zr—Pr composite oxide that is a composite oxide of zirconium and praseodymium. A proportion of a mass of praseodymium oxide contained in the Zr—Pr composite oxide relative to a total mass of zirconium oxide and praseodymium oxide contained in the Zr—Pr composite oxide may be 11% or more and 90% or less.

The present invention discloses a hydroisomerization catalyst and a preparation method thereof, and a mixed C4 olefin hydroisomerization method, the hydroisomerization catalyst comprises a carrier and an active component loaded on the carrier, the carrier comprises a mixture of a carrier matrix and a modified metal, the modified metal is selected from at least one of VIB group metals, and the active component is selected from at least one of C4-C4 olefin and C4-C4 olefin. The active component comprises a metal M and / or an oxide thereof, and the metal M is selected from at least one of metal palladium, metal platinum, metal rhodium and metal ruthenium. The catalyst can catalyze the hydroisomerization conversion of butene-1 into butene-2, and has the advantages of high butene-1 conversion rate and high butene-2 selectivity.

A grease composition that includes at least an oil-based medium, a thickener, and a fullerene-like nano-structure. The fullerene-like nano-structure includes a plurality of layers each comprised of a metal chalcogenide composition has a molecular formula of MX2, where M is a metallic element selected from the group consisting of titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), zirconium (Zr), niobium (Nb), molybdenum (Mo), technetium (Tc), ruthenium (Ru), rhodium (Rh), palladium (Pd), silver (Ag), cadmium (Cd), hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt), gold (Au), mercury (Hg) and combinations thereof, and X is a chalcogen element selected from the group consisting of sulfur (S), selenium (Se), tellurium (Te), oxygen (O) and combinations thereof.

A hydrometallurgical process for recovering a plurality of metals from a complex rare and precious material, comprising the following steps: step 1: adding a complex rare and precious material to a hydrochloric acid solution, adding an oxidant for reaction, and then performing filtration to obtain a chlorination liquid and a chlorination residue; step 2: using two-stage counter-current gold loading to obtain a gold-loaded liquid and a post-loading liquid, reducing the gold-loaded liquid, performing clarification to obtain an organic phase, and filtering a precipitate to separate a post-reduction liquid and sponge gold; performing evaporation and concentration on the post-reduction liquid to produce a concentrate 1 and a condensate; and cooling and crystallizing the concentrate, performing filtration to obtain residual oxalic acid, and returning the residual oxalic acid to the reduction process and a post-crystallization liquid to gold loading; step 3: performing low-temperature distillation on the post-loading liquid to obtain a concentrate 2; step 4: performing high-temperature distillation on the concentrate 2 to obtain a concentrate 3; step 5: performing directional crystallization and centrifugal filtration on the concentrate 3 to obtain a crystallization residue and selenous acid; and step 6: washing the crystallization residue by using cold water or a low-acid-level condensate produced in step 3, and performing filtration to obtain a tellurium residue and a palladium-platinum-rhodium-rich liquid.

The invention relates to a method for removing impurity ions in high-level liquid waste by using a 3-oxa-glutaramide extractant, which comprises the following steps: mixing and stirring a 3-oxa-glutaramide extractant solution and the high-level liquid waste, carrying out extraction reaction, and removing an organic phase containing the impurity ions to obtain a water phase rich in ruthenium and rhodium ions. Compared with the prior art, the method has the advantages that the impurity ions in the ruthenium and rhodium solution are extracted by using the 3-oxa-pentanediamide extraction agent, so that the separation of ruthenium and rhodium from impurity elements is realized.

A catalyst suitable for dehydrogenation of hydrocarbons may include from 0.0005 wt.% to 0.1 wt.% of platinum, palladium, rhodium, iridium, ruthenium, osmium, or combinations thereof; from 0.1 wt.% to 10 wt.% of gallium, indium, thallium, or combinations thereof; from 0.1 wt.% to 5 wt.% of lanthanum, yttrium, or zirconium; at least 85 wt.% support, and from 0 wt.% to 0.001 wt.% cerium.

The present disclosure provides an exhaust gas purification device capable of efficiently reducing NOx even after high-temperature exhaust gas flows in, and a method for manufacturing the same. This exhaust gas purification device is provided with: a substrate having an upstream end and a downstream end; a first catalyst layer formed across a first region between the upstream end and a first position; and a second catalyst layer including second rhodium particles formed across a second region between the downstream end and a second position. The first catalyst layer includes a first rhodium-containing catalyst and a first cerium-containing oxide. The average value of the particle size distribution of first rhodium particles contained in the first rhodium-containing catalyst is 2-10 nm. On the basis of the total weight of rhodium contained in the first rhodium-containing catalyst, the amount of solid-solution rhodium in the first metal oxide carrier is less than 17 wt%.

The invention relates to a forming method for composite electroplating of an MEMS (Micro Electro Mechanical System) probe. Structural patterns of a needle tip or / and a needle body are / is photoetched through a micro-electro-mechanical process, the needle tip or / and the needle body is / are formed through electroplating of a composite plating solution after pretreatment, the composite plating solution is obtained by mixing a metal base solution and a turbid liquid, the metal base solution is a nickel base solution and / or a rhodium base solution, and the turbid liquid is a nickel base solution and / or a rhodium base solution. The suspension is formed by suspending nano-powder in water through a dispersing agent. Compared with the prior art, the technology provided by the invention has the following advantages that the MEMS process technology is combined with the composite plating solution to be used for various probe structures, and the performance of the prepared material is greatly improved compared with that of a pure metal coating; the composite plating solution prepared from the plating solution and the second-phase particles is high in stability, and the electroplating process is easy to operate; the nickel-based composite plating solution can be used for obtaining a main body material with higher hardness, better wear resistance and better flexural property; the rhodium-based composite plating solution is used for preparing a needle point material, has higher hardness and wear resistance, and improves the brittle fracture problem.

A process for producing amines by reductive amination, the process includes introducing a feed stream, the feed stream comprising an amino alcohol and a reducing agent, and hydrogen in a reaction zone of a reactor, and contacting the feed stream with a catalyst in the reaction zone. A hydrogen flow rate into the reaction zone is adjusted, and a product stream comprising ethyleneamines is extracted. The catalyst includes a carrier component selected from alumina, silica, and combinations thereof; and an active component having a first metal, a second metal, and a third metal. The first metal is selected from cobalt, nickel, and copper, the second metal is selected from rhenium, ruthenium, chromium, zinc, sodium, calcium, magnesium, strontium, lithium, potassium, barium, cesium, lanthanum, tungsten, iron, silver, titanium, manganese, aluminum, rhodium, platinum, palladium, iridium, and combinations thereof, and the third metal is niobium.

The application discloses a phosphine ligand modified nitrogen-doped graphene oxide / porous carbon supported metal catalyst and a preparation method and application thereof. The catalyst comprises phosphine ligand modified nitrogen-doped graphene oxide / porous carbon and rhodium supported on the nitrogen-doped graphene oxide / porous carbon; and the molar ratio of rhodium to phosphine is 1:1-100 in terms of elements. The phosphine ligand modified nitrogen-doped graphene oxide / porous carbon supported metal catalyst has better catalytic activity and product selectivity.

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 invention discloses a method for preparing hydrogenated butadiene-acrylonitrile rubber latex based on a water-insoluble rhodium metal catalyst, which comprises the following steps: emulsifying a surfactant, a reducing agent, the water-insoluble rhodium metal catalyst and a cocatalyst, adding a polymerization initiator, and carrying out polymerization reaction at a polymerization temperature, and adding a terminator, raising the temperature, and carrying out hydrogenation reaction under high-pressure hydrogen to obtain the hydrogenated nitrile rubber latex. According to the method disclosed by the invention, the two processes of NBR emulsion polymerization and NBR latex hydrogenation in the existing HNBR latex preparation method are simplified, and the method has the advantages of short process flow, high efficiency, low energy consumption, greenness and the like. The hydrogenation degree of the hydrogenated rubber latex prepared by the method is 50-100%, the conversion rate is 60-85%, the particle size of the hydrogenated rubber latex is 30-60 nm, nano-particle micelles in the latex are stable in performance, and the nano-micelles are good in size uniformity, small in particle size distribution range and not prone to demulsification.