Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
  • H01B1/06—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of other non-metallic substances
  • H01B1/08—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of other non-metallic substances oxides
• • 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
• • 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
  • B01J23/652—Chromium, molybdenum or tungsten
  • B01J23/6527—Tungsten
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
  • C01G55/00—Compounds of ruthenium, rhodium, palladium, osmium, iridium, or platinum
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
  • C25B11/00—Electrodes; Manufacture thereof not otherwise provided for
  • C25B11/04—Electrodes; Manufacture thereof not otherwise provided for characterised by the material
  • C25B11/051—Electrodes formed of electrocatalysts on a substrate or carrier
  • C25B11/073—Electrodes formed of electrocatalysts on a substrate or carrier characterised by the electrocatalyst material
  • C25B11/075—Electrodes formed of electrocatalysts on a substrate or carrier characterised by the electrocatalyst material consisting of a single catalytic element or catalytic compound
  • C25B11/077—Electrodes formed of electrocatalysts on a substrate or carrier characterised by the electrocatalyst material consisting of a single catalytic element or catalytic compound the compound being a non-noble metal oxide
  • C25B11/0775—Electrodes formed of electrocatalysts on a substrate or carrier characterised by the electrocatalyst material consisting of a single catalytic element or catalytic compound the compound being a non-noble metal oxide of the rutile type
• • 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
  • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
  • B01J31/16—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes

Definitions

• the present invention relates to a new oxygen-containing compound of rhodium and tungsten, Rh -WO and to a manufacturing process therefor.
• the present invention concerns a compound Rh WO- DESCRIPTION OF THE PREFERRED EMBODIMENTS
• the new compound was prepared from powdered and W0 which were mixed in equimolecular quantities, then comminuted and pelletized.
• the starting oxide Rh O was obtained by pyrolysis at 500 C. of pure rhodium nitrate supplied by Fluka, whereas the WO was a product supplied by UCB, chemical analysis grade.
• the unit cell has the following parameters:
• the unit cell contains two molecules of Rh WO
• the intensities of the lines and the observed interplanar 3,735,270 Patented May 29, 1973 ice spacings determined in the X-ray crystallographic analysis are given in the following table.
• Rh WO In order to measure the electrical conductivity of the obtained Rh WO the powder resulting from comminuting the porous disc was again pelletized under the same conditions used for pelletizing the Rh O -WO mixture.
• the measured electrical conductivity was in the range of 10 (ohm-cm.)"
• the obtained Rh WO' is thus really a semiconductor and its forbidden gap, or energy gap, amounts to 0.03 e.v.
• forbidden gap and energy gap refer to the distance between the top of the valence band and the bottom of the conduction band; these terms appear, for instance, in Physics and Technology of Semiconductor Devices by A. S. Grove, pages 91-95 and 102.
• the manufacturing process for the compound of the present invention is very easy and the operative conditions are easily reproducible.
• the new compound Used as an anodic operative surface in the electrolysis of sodium chloride, the new compound presents very interesting polarization properties and is very resistant to electrochemical attack under cellconditions.
• the compound Rh /WO of the present invention is very useful for industrial applications not only as an electrode in various electrochemical processes, but also as an oxidation catalyst in organic chemistry or as a component in composite semiconductive devices.
• the starting materials were obtained from Fluka, CH- 9470 Buchs (Switzerland) and UCB, 33 rue dAnderlecht, 1620 Drogenbos (Belgium).
• the trademark designation of the rhodium nitrate was rhodium (III) -nitrat Dihydrat purissimum No. 83,760.
• the trademark designation of the W0 was anhydride tungstique pour analyse No. 1925.
• the rhodium nitrate was supplied in a purity grade designated as purissimum which meant a chemical analysis in weight-percent as follows:
• the W was supplied in a purity grade designated as: chemical analysis which meant a chemical analysis in weight-percent as follows:
• Rh WO Chlorides Max. 0.0015 Heavy metals (-Pb) Max. 0.002 Iron (Fe) Max. 0.004 Molybden (Mo) Max. 0.05 Ammonium (NH Max. 0.0015 Arsenic (As) Max. 0.0015 W0 Balance
• -Pb Heavy metals
• Fe Iron
• Mo Molybden
• Ammonium NH Max. 0.0015
• overvoltage is used herein in the same since as it is used at pages 48 8-492 of Physical Chemistry by Walter J. Moore, Prentice-Hall Inc., second edition.
• the coated plate was used as anode for the electrolysis of a brine containing 250 g. NaCl/ kg. of solution saturated with chlorine at 60 C. and at an approximate pH of 2. Under these conditions, the coated plate of this example showed an overvoltage in the range 250 mv. under an anodic current density of 10 kajmfi.
• the coated plate was used as anode in a cell with a flowing mercury cathode for the electrolysis of a brine saturated with sodium chloride and chlorine, between and C., under a constant anode-cathode potential difference, the test being stopped when the current density was reduced to one half of its initial value (initial value generally was between 30 and 40 ka./m. Under these conditions, the tested plate produced 9 tons of chlorine per square meter of active surface; the rhodium consumption lay below 200 mg. per ton of chlorine produced under an average current density of 20 ka./m.
• the Well homogenized mixture has a particle size distribution lower than Lu.
• the pelletizing is carried out without any binding additive.
• Rh WO crystallized in the tetragonal system under the trirutile form the parameters a and c being 4.609 and 9.083 A. respectively, having an electrical conductivity of 10- (ohm-cm.) and an energy gap of 0.03 erv.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Electrochemistry (AREA)
• Inorganic Chemistry (AREA)
• Metallurgy (AREA)
• Inorganic Compounds Of Heavy Metals (AREA)
• Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
• Conductive Materials (AREA)
• Catalysts (AREA)
• Electrodes For Compound Or Non-Metal Manufacture (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=19726436

Family Applications (1)

Country Status (9)

Families Citing this family (1)

• 1970
  • 1970-07-29 LU LU61435D patent/LU61435A1/xx unknown
• 1971
  • 1971-07-08 ES ES393034A patent/ES393034A1/es not_active Expired
  • 1971-07-08 BE BE769679A patent/BE769679A/xx not_active IP Right Cessation
  • 1971-07-19 FR FR7126435A patent/FR2099649B1/fr not_active Expired
  • 1971-07-21 DE DE2136393A patent/DE2136393C3/de not_active Expired
  • 1971-07-28 NL NLAANVRAGE7110388,A patent/NL168794C/xx not_active IP Right Cessation
  • 1971-07-28 JP JP5609971A patent/JPS5338280B1/ja active Pending
  • 1971-07-29 US US00167517A patent/US3736270A/en not_active Expired - Lifetime
  • 1971-07-29 GB GB3574671A patent/GB1306479A/en not_active Expired

Also Published As

Similar Documents