Classifications

• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B7/00—Halogens; Halogen acids
  • C01B7/01—Chlorine; Hydrogen chloride
  • C01B7/03—Preparation from chlorides
  • C01B7/04—Preparation of chlorine from hydrogen chloride
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
  • B01J23/40—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals of the platinum group metals
  • B01J23/46—Ruthenium, rhodium, osmium or iridium
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
  • B01J23/40—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals of the platinum group metals
  • B01J23/46—Ruthenium, rhodium, osmium or iridium
  • B01J23/462—Ruthenium
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
  • B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/56—Platinum group metals
  • B01J23/62—Platinum group metals with gallium, indium, thallium, germanium, tin or lead
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
  • B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/56—Platinum group metals
  • B01J23/62—Platinum group metals with gallium, indium, thallium, germanium, tin or lead
  • B01J23/622—Platinum group metals with gallium, indium, thallium, germanium, tin or lead with germanium, tin or lead
  • B01J23/626—Platinum group metals with gallium, indium, thallium, germanium, tin or lead with germanium, tin or lead with tin
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
  • B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/56—Platinum group metals
  • B01J23/63—Platinum group metals with rare earths or actinides
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
  • B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/56—Platinum group metals
  • B01J23/64—Platinum group metals with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
  • B01J23/644—Arsenic, antimony or bismuth
  • B01J23/6445—Antimony
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
  • B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/56—Platinum group metals
  • B01J23/64—Platinum group metals with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
  • B01J23/644—Arsenic, antimony or bismuth
  • B01J23/6447—Bismuth
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/89—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals
  • B01J23/892—Nickel and noble metals
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J35/00—Catalysts, in general, characterised by their form or physical properties
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J35/00—Catalysts, in general, characterised by their form or physical properties
  • B01J35/20—Catalysts, in general, characterised by their form or physical properties characterised by their non-solid state
  • B01J35/23—Catalysts, in general, characterised by their form or physical properties characterised by their non-solid state in a colloidal state
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J35/00—Catalysts, in general, characterised by their form or physical properties
  • B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
  • B01J35/391—Physical properties of the active metal ingredient
  • B01J35/393—Metal or metal oxide crystallite size
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J35/00—Catalysts, in general, characterised by their form or physical properties
  • B01J35/40—Catalysts, in general, characterised by their form or physical properties characterised by dimensions, e.g. grain size
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J35/00—Catalysts, in general, characterised by their form or physical properties
  • B01J35/50—Catalysts, in general, characterised by their form or physical properties characterised by their shape or configuration
  • B01J35/56—Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional monoliths
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J35/00—Catalysts, in general, characterised by their form or physical properties
  • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
  • B01J35/61—Surface area
  • B01J35/613—10-100 m2/g
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J35/00—Catalysts, in general, characterised by their form or physical properties
  • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
  • B01J35/63—Pore volume
  • B01J35/635—0.5-1.0 ml/g
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J35/00—Catalysts, in general, characterised by their form or physical properties
  • B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
  • B01J35/66—Pore distribution
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/02—Impregnation, coating or precipitation
  • B01J37/0201—Impregnation
  • B01J37/0203—Impregnation the impregnation liquid containing organic compounds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/02—Impregnation, coating or precipitation
  • B01J37/0201—Impregnation
  • B01J37/0211—Impregnation using a colloidal suspension
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/34—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation
  • B01J37/349—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation making use of flames, plasmas or lasers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
  • B01J21/12—Silica and alumina

Definitions

• the present invention relates to a process for the preparation of chlorine by gas phase oxidation with a supported catalyst based on ruthenium, characterized in that the catalyst support has a plurality of pores, with a pore diameter> 50 nm and ruthenium and / or ruthenium compounds containing nanoparticles as catalytically active Components carries.
• the oxidation of hydrogen chloride to chlorine is an equilibrium reaction.
• the position of the equilibrium shifts with increasing temperature to the detriment of the desired end product. It is therefore advantageous to use catalysts with the highest possible activity, which allow the reaction to proceed at low temperature.
• the first catalysts for the hydrogen chloride oxidation contained as active component copper chloride or oxide and were already described in 1868 by Deacon. However, these showed low activity at low temperature ( ⁇ 400 0 C). Although the activity could be increased by increasing the reaction temperature, it was disadvantageous that the volatility of the active components at high temperatures led to a rapid decrease in the catalyst activity and to the discharge of the active component from the reactor.
• EP 0184413 describes the oxidation of hydrogen chloride with catalysts based on chromium oxides.
• the process realized thereby requires high catalyst loadings due to insufficient catalyst activity and high reaction temperatures.
• the first catalysts for the hydrogen chloride oxidation with the catalytically active component ruthenium were already described in 1965 in DE 1567788; in this case starting from RuCb, for example supported on silica or alumina.
• RuCb / SiOa catalysts was very low.
• Ru-based catalysts with the active component ruthenium oxide or ruthenium mixed oxide and as carrier material various oxides, such as, for example, titanium dioxide, zirconium oxide, etc., have been claimed in DE-A 19748299.
• the content of ruthenium oxide is 0.1% by mass to 20% by mass and the average particle diameter of ruthenium oxide is 1.0 nm to 10.0 nm.
• Further Ru catalysts supported on titanium dioxide or zirconium dioxide are known from DE-A 19734412.
• ruthenium-carbonyl complexes ruthenium salts of inorganic acids
• ruthenium-nitrosyl complexes ruthenium Amine complexes
• ruthenium complexes of organic amines or ruthenium-acetylacetonate complexes In a preferred embodiment, TiC> 2 was used as a carrier in the form of rutile.
• DE 102007020154Al and DE 102006024543 A1 describe a process for catalytic hydrogen chloride oxidation, in which the catalyst is tin dioxide (as carrier), preferably tin dioxide in the cassiterite structure and at least one halogen-containing ruthenium compound (DE 102007020154Al) or at least one oxygen-containing ruthenium compound (DE102006024543A1). contains.
• the ruthenium-free catalysts previously developed for the Deacon process are either too inactive or too unstable.
• the ruthenium-supported catalysts described hitherto are suitable in principle for use in the Deacon process, the preferred supports rutile titanium dioxide and cassiterite tin dioxide have only small surfaces due to their crystalline structure, which is disadvantageous for their use as carriers in the HCl oxidation ,
• the object of the present invention was therefore to provide a catalytic system for the oxidation of hydrogen chloride, which offers a higher specific (on the ruthenium content) related activity than the catalysts known from the prior art.
• the present invention relates to a catalyst material for the thermocatalytic production of chlorine from hydrogen chloride and oxygen-containing gas, based on a ruthenium-based carrying supported catalyst, characterized in that the catalyst support has a plurality of pores, with a pore diameter> 50 nm and ruthenium and / or ruthenium compounds containing nanoparticles as catalytically active components.
• the thermocatalytic production of chlorine from hydrogen chloride and oxygen-containing gas is also generally referred to hereinafter as the Deacon process.
• At least 50%, more preferably at least 80%, of the pore volume of the catalyst material of the present invention is present in pores whose diameter is within the macroporous range, i. > 50 nm.
• This macroporosity allows a uniform loading of the catalyst support with nanoparticles, prevents the blocking of pores by agglomeration of nanoparticles and leads to reduced pore diffusion limitation during the Deacon reaction.
• mercury porosimetry is used to determine the pore volume and the pore diameter.
• the measurement is based on a mercury contact angle of 130 ° and a surface tension of 480 dyn / cm 2 .
• the catalyst material preferably comprises one or more compounds of the series: aluminum compounds, silicon compounds, titanium compounds, zirconium compounds or tin compounds as support material, particularly preferably aluminum compounds and / or silicon compounds and very particularly preferably oxides, mixed oxides or mixed oxides of one or more of the metals of the series: aluminum, Silicon, titanium, zirconium or tin. Particularly preferred are mixed oxides of aluminum and silicon.
• binders are added, such as. B. ⁇ -Al 2 ⁇ 3 , whose primary function is not that of a carrier of the active component.
• the ruthenium-containing nanoparticles present on the catalyst material as catalytically active component preferably comprise one or more compounds from the series: ruthenium oxides, ruthenium mixed oxides, mixed ruthenium oxides, ruthenium oxyhalides, ruthenium halides or metallic ruthenium. Particular preference is given to ruthenium chloride, ruthenium oxychloride or mixtures of ruthenium oxide and ruthenium chloride.
• the ruthenium-containing nanoparticles present on the catalyst preferably have at least 50% of a maximum diameter of 50 nm, more preferably at least 50% have a diameter of 5 nm to 50 nm, very preferably at least 80% have a diameter of 5 nm 50 nm. Most preferably, the average diameter of the present on the catalyst, ruthenium-containing nanoparticles, 10 to 30 nm.
• the ruthenium content of the catalysts is preferably set at up to 20% by weight, preferably 0.1 to 20% by weight, more preferably 0.5 to 5% by weight, based on the total mass of the catalyst. Excessive loading may result in adverse agglomeration of nanoparticles.
• Additional nanoparticles with the function of a further active component or as promoters are preferably present on the catalyst material, particularly preferably one or more further metals, metal compounds and mixed compounds of the elements Ag, Au, Bi, Ce, Co, Cr, Cu, Ni, Sb, Sn , Ti, W, Y, Zn, Zr and the platinum metals, most preferably the elements Bi, Sb, Sn and Ti.
• a mass fraction of the present on the catalyst material additional nanoparticles of up to 20% by mass, more preferably up to 10% by mass, based on the total mass of the catalyst. Excessive loading may result in adverse agglomeration of nanoparticles.
• the additional nanoparticles present on the catalyst have at least 50% of a maximum diameter of 50 nm, more preferably at least 50% have a diameter of 3 nm to 50 nm, most preferably at least 80% have a diameter of 3 nm to 50 nm. Most preferably, the average diameter, the existing on the catalyst, additional nanoparticles, between 5 and 30 nm.
• nanoparticles which contain at least ruthenium and at least one further metal, preferably Ag, Au, Bi, Ce, Co, Cr, Cu, Ni, Sb, Sn, Ti, W, Y, Zn, are present on the catalyst.
• Zr and platinum metals as a promoter most preferably Bi, Sb, Sn and Ti, ie can be referred to as bimetallic or multimetallic.
• the nanoparticles characterized in this way contain oxides, mixed oxides, mixed oxides, oxyhalides, halides, metals and alloys.
• the bimetallic or multimetal nanoparticles present on the catalyst have at least 50% of a maximum diameter of 50 nm, more preferably at least 50% have a diameter of 5 nm to 50 nm, most preferably at least 80% have a diameter of 5 nm up to 50 nm. Most preferably, the average diameter of the present on the catalyst, bimetallic or multimetal nanoparticles 10 to 30 nm.
• a mass fraction of the bimetallic or multimetal nanoparticles present on the catalyst of up to 30 wt .-% is set, particularly preferably up to 20 wt .-%, based on the total mass of the catalyst. Excessive loading leads to disadvantageous agglomerations of nanoparticles.
• the nanoparticles are preferably prepared by flame pyrolysis.
• a preferred method of preparation is as follows:
• At least one precursor is presented in powder form. If bimetallic or multimetal nanoparticles are to be prepared, various pulverulent precursors are preferably poured together and mixed. These powders are fed to a plasma chamber or free flame and vaporized abruptly therein. The generated gaseous metal compounds are discharged from the plasma and condense in a cooler area, whereby nanoparticles are formed with a defined size distribution. These nanoparticles are stabilized in an emulsion by the addition of surfactants and detergents. Preferably, water or an organic solvent is used for the preparation of the emulsion.
• This emulsion, or a mixture of two or more emulsions containing the active component, further active components and / or promoters, is then used to impregnate a catalyst support, preferably by a method commonly referred to in the specialist literature as "incipient wetness".
• incipient wetness a method commonly referred to in the specialist literature as "incipient wetness”.
• this method as many of the active components containing impregnation solution is presented as the carrier to be impregnated can just record and thus ensures that the active components are completely absorbed by the carrier.
• Patent application US20080277270-A1 can be found, for example, the patent application US20080277270-A1.
• the catalyst is then calcined at elevated temperatures.
• this calcination is carried out in an atmosphere containing oxygen, more preferably in air or an inert gas-oxygen mixture.
• the temperature is up to 800 0 C, preferably between 250 0 C and 600 0 C.
• the calcination time is appropriately selected preferably between Ih and 50h.
• the catalyst impregnated with the emulsion is preferably dried before calcination, preferably at reduced pressure and expediently between 1 h and 50 h.
• promoters are compounds of basic metals in question (eg, alkali, alkaline earth and rare earth metal salts), preferred are compounds of alkali metals, especially Na and Cs and alkaline earth metals, particularly preferred are compounds of alkaline earth metals, in particular Sr and Ba.
• the basic metals are used as oxides, hydroxides, chlorides, oxychlorides or nitrates.
• these types of promoters are applied to the catalyst by impregnation or CVD methods.
• the carrier used according to the invention is preferably commercially available (for example from Saint Gobain Norpro).
• the catalysts according to the invention for the hydrogen chloride oxidation are characterized by high activity coupled with high stability at high temperatures.
• the catalytic hydrogen chloride oxidation may preferably be adiabatic or isothermal or approximately isothermal, batchwise, but preferably continuously or as a fixed bed process, preferably as a fixed bed process, more preferably in tube bundle reactors to heterogeneous catalysts at a reactor temperature of 180 to 500 0 C, preferably 200 to 400 0th C, more preferably 250 to 380 0 C and a pressure of 1 to 25 bar (1000 to 25000 hPa), preferably 1.2 to 20 bar, more preferably 1.5 to 17 bar and in particular 2.0 to 15 bar are performed ,
• Typical reactors in which the catalytic hydrogen chloride oxidation is carried out are fixed bed or fluidized bed reactors.
• the catalytic hydrogen chloride oxidation can preferably also be carried out in several stages.
• a further preferred embodiment of a device suitable for the method consists in using a structured catalyst bed in which the catalyst activity increases in the flow direction.
• Such structuring of the catalyst bed can be done by different impregnation of the catalyst support with active material or by different dilution of the catalyst with an inert material.
• an inert material for example, rings, cylinders or balls of titanium dioxide, zirconium dioxide or mixtures thereof, alumina, steatite, ceramic, glass, graphite or stainless steel can be used.
• the inert material should preferably have similar external dimensions.
• Suitable shaped catalyst bodies are shaped bodies of any shape, with preference being given to tablets, extrudates, rings, cylinders, stars, wagon wheels or spheres, particular preference being given to rings, cylinders or star strands as a mold.
• the dimensions (diameter in the case of spheres) of the shaped bodies are preferably in the range from 0.2 to 10 mm, particularly preferably 0.5 to 7 mm.
• the support may also be a monolith of support material.
• An alternative preferred embodiment is foams, sponges or the like with three-dimensional connections within the carrier body, as well as monoliths and carrier bodies with cross-flow channels.
• the monolithic carrier may have a honeycomb structure, but also an open or closed cross-channel structure.
• the monolithic carrier has a preferred cell density of 100 to 900 cpsi (cells per square inch), more preferably 200 to 600 cpsi.
• a monolith according to the present invention is e.g. in "Monoliths in multiphase catalytic processes - aspects and prospects" by F. Kapteijn, J.J. Heiszwolf, T.A. Nijhuis and J.A. Moulijn, Cattech 3, 1999, p24.
• the conversion of hydrogen chloride in a single pass is in the range of 15 to 100% and may preferably be limited to 15 to 90%, preferably 40 to 90%, particularly preferably 60 to 90%.
• unreacted hydrogen chloride can be partially or completely recycled to the catalytic hydrogen chloride oxidation.
• the volume ratio of hydrogen chloride to oxygen at the reactor inlet is preferably 1: 1 to 20: 1, particularly preferably 2: 1 to 8: 1, very particularly preferably 2: 1 to 6: 1.
• the heat of reaction of the catalytic hydrogen chloride oxidation can be used advantageously for the production of high-pressure steam.
• This can be used to operate a phosgenation reactor and / or distillation columns, in particular isocyanate distillation columns.
• the chlorine formed is separated off.
• the separation step usually comprises several stages, namely the separation and optionally recycling of unreacted hydrogen chloride from the product gas stream of the catalytic hydrogen chloride oxidation, the drying of the obtained, substantially chlorine and oxygen-containing stream and the separation of chlorine from the dried stream.
• the separation of unreacted hydrogen chloride and water vapor formed can be carried out by condensation of aqueous hydrochloric acid from the product gas stream of hydrogen chloride oxidation by cooling. Hydrogen chloride can also be absorbed in dilute hydrochloric acid or water.
• Example 1 (comparative example: Preparation of a catalyst not according to the invention)
• Stable oxides of Ru (RuO 2 ), Sn (SnO 2 ), Ni (NiO), Sb (Sb 2 O 5 ), Zr-Y (90 mass% ZrO 2 , 10 mass% Y 2 Os), Ti (TiO 2 ), Bi (Bi 2 O 5 ) were presented as ⁇ m-scale powder. These powders were individually (samples with the names 2a-b, 2e-i -> monometallic nanoparticles) or premixed (samples with the names 2c-d - ⁇ bimetallic nanoparticles) supplied to a plasma chamber and therein (at a temperature above 20,000 K) evaporates abruptly.
• the resulting gaseous metal compounds were discharged from the plasma and condensed in a cooler range (temperature less than 500 0 C), whereby nanoparticles were formed with a defined size distribution. These nanoparticles were stabilized in an aqueous emulsion by adding an amine-based non-ionic comb polymer (manufacturer: SDC material) with the content of nanoparticles adjusted to 7.5% by weight.
• SDC material an amine-based non-ionic comb polymer
• the wet catalyst samples were dried between the impregnation steps and finally at 110 0 C for 2-5 h and calcined at 550 0 C for 2 h in air.
• the mass fraction of the metallic content of the nanoparticles in the total mass of the catalysts can be taken from Table 1 (determined by means of XRF).
• Example 3 (Comparative Example): Test of a catalyst not according to the invention (from Example 1)
• Example 4 Test of Inventive Catalysts (from Example 2)
• each Ig of the shaped catalyst body with the name 2a-i were diluted with inert Spheriglaskugeln in a quartz reaction tube (inner diameter 10 mm) presented.
• the mixtures each with a gas mixture (10 L / h), composed of 1 L / h of hydrogen chloride, 4 L / h of oxygen, 5 L / h of nitrogen at 380 0 C for about 16h.
• the temperature was lowered to 330 0 C and determines the space-time yield (starting-RZA).
• starting-RZA space-time yield
• the temperature was raised to 430 0 C.
• the temperature was lowered in intervals to 330 0 C (RZA after xh).
• the space-time yield was determined in which the product gas stream of the respective reactors for about 15 min. was passed through a 20% potassium iodide solution and the resulting iodine was then titrated with 0.1 N thiosulfate standard solution (duplicate determination). From the so determined amount of chlorine specific (on the ruthenium content) space-time yield (RZA) was determined according to the following formula (Tab. 3a / b):
• RZA Ru g (Chloro) * g "1 (ruthenium mass on the catalyst used) * h " 1 (time)
• the RZA Ru evolution was modeled with a power approach:
• the stability (modeled deactivation parameter -b) of some exemplified, inventive catalysts (2a, 2b, 2g, 2h, 2i) is obviously in some cases significantly higher than that of the prior art catalyst not according to the invention.
• the specific initial activity of some exemplified, erf ⁇ ndungswasher catalysts (2b, 2f, 2i) is obviously partially significantly higher than that of the non-inventive catalyst according to the prior art.
• the catalyst samples 2a and 2c even have significantly higher (high temperature) stability and significantly higher initial activity than the prior art catalyst.
• Example 5 Size distribution of the nanoparticles on the catalyst
• Fig. 1 (Cat. 2a): 34 primary particles with a diameter between 5 and 34 nm (mean value of 16 nm) were counted.
• Fig. 2 (Cat 2b): The primary particle distribution (ruthenium dioxide and tin dioxide) is similar to that of 2a.
• Fig. 3 (Cat. 2c): The primary particle distribution (ruthenium dioxide and tin dioxide) is similar to that of
• Fig. 4 (Cat. 2d): The primary particle distribution (ruthenium dioxide and tin dioxide) is similar to that of 2a.
• ruthenium dioxide on rutile TiC> 2 (see Example 1) evidently exists as a carrier-coating layer owing to the comparable lattice spacing of the two rutile structures ("Development of an improved HCl oxidation process: structure of the RuCVrutile Ti ⁇ 2 catalyst "by Seki, Kohei, Iwanaga, Kiyoshi, Hibi, Takuo, Issoh, Koharto, Mori, Yasuhiko, Abe, Tadashi in Studies in Surface Science and Catalysis (2007), 172 (Science and Technology in Catalysis 2006), 55-60).
• this catalyst are compared with ruthenium catalysts on the basis of Al 2 O 3 or SiO 2, which have a significantly lower activity despite assumable high dispersion.
• the high dispersion is on these carriers in comparison with the planar Application to rutile TiO 2 detrimental to the catalytic properties.
• nano-structured supported ruthenium catalysts according to the invention with defined ruthenium primary particle sizes are obviously even superior to ruthenium-supported catalysts based on RuUl-TiO 2 .

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Physics & Mathematics (AREA)
• Inorganic Chemistry (AREA)
• Optics & Photonics (AREA)
• Health & Medical Sciences (AREA)
• Plasma & Fusion (AREA)
• Toxicology (AREA)
• Catalysts (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=42735804

Family Applications (1)

Country Status (9)

Families Citing this family (17)

Family Cites Families (14)

• 2009
  • 2009-07-25 DE DE102009034773A patent/DE102009034773A1/de not_active Withdrawn
• 2010
  • 2010-07-14 KR KR1020127001664A patent/KR20120040701A/ko not_active Application Discontinuation
  • 2010-07-14 US US13/384,792 patent/US20120148478A1/en not_active Abandoned
  • 2010-07-14 WO PCT/EP2010/004287 patent/WO2011012226A2/de active Application Filing
  • 2010-07-14 IN IN739DEN2012 patent/IN2012DN00739A/en unknown
  • 2010-07-14 EP EP10732315A patent/EP2459312A2/de not_active Withdrawn
  • 2010-07-14 CN CN2010800325889A patent/CN102711986A/zh active Pending
  • 2010-07-14 JP JP2012520932A patent/JP2013500145A/ja active Pending
  • 2010-07-23 TW TW099124240A patent/TW201117880A/zh unknown

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events