Journal Archive

Platinum Metals Rev., 1969, 13, (3), 120

NEW PATENTS: July 1969


Metallising Compositions

e. i. du pont de nemours & co. British Patent 1,144,930

A noble metal alloy metallising composition comprises a Pd-Au, Pt-Au, Ag-Au, Ag-Pt or Pd-Pt alloy in powder form (average particle size not greater than 40 μ). The alloy powder is dispersed in an organic vehicle (which may contain a vitreous binder) and constitutes 10−70 wt% of the metallising composition.

Finely Divided Metals of the Platinum Group

monsanto co. British Patent 1,146,530

A salt of a Pt metal is reduced in the presence of an alcohol, acetal, ketone, ether, carboxylic acid ester or olefine which complexes the metal formed. The complex is then decomposed.

Noble Metal Alloy for Porcelain Cladding

deutsche gold- & silber-scheideanstalt U.S. Patent 3,413,723

A dental alloy adapted for fixing on porcelain coverings consists essentially of 80−90% Au, 5−15% Pt, 0.1−2% In, 0.1−2% Sn and 0.05−1% Re. Other compositions with the same components are specified.

Production of Alloys of Platinum Metals

johnson matthey & co. ltd Dutch Patent 68.09,169

Thermal sensitivity in Pt metal alloys is reduced by introducing a maximum of 20 at.% of one or more of Se, Ti, V, Y, Zr, Nb, Hf and the lanthanides.

Improved Method of Coating and Inlaying

johnson matthey & co. ltd Italian Patent 822,094

Phosphor bronze strip inlaid with Pd may be produced by means of rolling processes including an intermediate layer of Ni, Fe, Co, Mo, or V.


Palladium-Nickel Alloy Plating Bath

kabushiki kaisha suwa seikosha nisshin kasei k.k. British Patent 1,143,178

A plating bath for electrodeposition of a Pd-Ni alloy comprises an aqueous solution of Pd and Ni ammines at specified critical concentrations. The relative proportions of Pd and Ni are such as to deposit an alloy with a Pd content of 30−90%. An example bath contains Pd(NH3)Cl2 and NiSO4.7H2O. Optional additives are a soluble salt of a naphthalene sulphonic acid and p − toluenesuplhonamide.

Deposition of Platinum Group Metals

national research development corp. British Patent 1,145,285

Pt or Rh is deposited on a Ni- or Ni/Fe alloy surface by (a ) subjecting the latter to a charging treatment, (b ) introducing H2 and (c ) bringing the treated surface into contact with a solution of a reducible Pt- or Rh-compound. The latter is reduced to metal by the H2. The surface is charged by cathodic treatment in an electrolytic bath.

Porous Cathode Body Coated with Osmium

philips electronic & associated industries ltd British Patent 1,145,967

A porous W cathode body, containing Ba compounds in its interior, is coated with Os by heating the body to an elevated temperature in an atmosphere of H2. The Os coating is formed by the reduction of OsO4. The heated body may be brought into contact with OsO4 vapour or immersed in a solution of OsO4.

Platinum Coatings

johnson matthey & co. ltd British Patent 1,147,563

A Pt-containing dispersion, which forms adherent coatings on the substrates to which it is applied, is prepared by reducing PtO2 and/or a mixture of PtO2 with at least one oxide of the metals Rh, Ru, Ir and Pd. The Pt content should be at least 50% of the metal content of the mixture.

Iridium Coated Graphite Articles

union carbide corp. British Patent 1,149,625

A graphite substrate, resistant to oxidation at temperatures up to 2,000°C, bears an adherent, substantially pore-free coating of Ir consisting of an inner layer adjacent to the graphite substrate. This inner layer is formed of sintered finely divided particles of Ir. An intermediate layer is vapour-plated before the electroplating of an outer Ir layer.

Coating Catalyst for Chemical Plating

sperry rand ltd U.S. Patent 3,414,427

The surface to be plated is treated with a solution of PdCl2 in an organic solvent in the presence of HCl or HF as complexing agent.


Laser Materials

minister of technology British Patent 1,142,321

In the production of single crystal calcium aluminate, CaCO2 and Al2O3 powders are melted in an Ir crucible in an Ar atmosphere. Single crystals are grown on the end of an Ir rod inserted into a crucible with a Pt heat shield.


Welding Iridium and Ruthenium or Their Alloys to Silver

international nickel ltd British Patent 1,145,071

Ag is welded to an Ir or to a Ru body (or an alloy of either) by interposing a bonding agent consisting of a Pd-Ag alloy containing 1−30% Pd (preferred 5%). The invention relates to Ir tips welded to Ag rods in sparking plugs.

Brazing Alloy Compositions

north american rockwell corp. U.S. Patent 3,411,900

An alloy with brazing characteristics equivalent to a Au-Ni braze contains 80−95 wt% Ag, 1−10 wt% Pd, 1−7.5 wt% Cu and 0.5−3.5 wt% Ni with the usual impurities. A preferred composition, in wt% contains 89.5−90.5 Ag, 4.5−5.25 Pd, 3.95−4.5 Cu and 0.90−1.25 Ni.

Brazing Alloy

national aeronautics and space administration U.S. Patent 3,413,115

A ductile joint is obtained using an alloy of 80−83% Pd, 13.5−16.5% Ag and the remainder Si. A preferred alloy contains 81.5% Pd, 15.0% Ag and 3.5% Si.


Improvements in or Relating to the Production of Acetic Acid

b.p. chemicals (u.k.) ltd British Patent 1,142,897

C2H4, steam and a gas containing O2 are reacted in the vapour phase at temperatures of 50−350°C over a supported catalyst comprising Pd metal together with a transition metal (Fe, Ni, Mo, Ce, Cu, Cr, Mn or Co) oxide or salt, or mixtures of oxides, or salts of the same or of different transition metals, e.g. Pd/Al2O3 impregnated with Cr acetate.

Improvements in and Relating to the Oxidation of Ferrous Compounds and to the Reduction of Ferric Compounds

johnson matthey & co. ltd British Patent 1,143,139

A feedstock containing Fe2+ or Fe3+ is reacted with O2 or H2 respectively in an acid solution in the presence of a catalyst comprising at least one Pt-group metal (Pt, Pd, or an alloy of Pt-Pd) on an inert support (charcoal) in a trickle column reactor. The feedstock may be obtained from a steel-pickling liquor or by extracting Fe ore with H2SO4 or HCl.

Dehydrocyclisation of Paraffins

shell internationale research mij. n.v. British Patent 1,143,147

A paraffin with 6−20 C per molecule is contacted at elevated temperatures (482−593°C) with a sulphided catalyst containing at least one noble metal from Group VIII (e.g. a sulphided Ir, Pd or Pt). The catalyst comprises 0.01−5% of the noble metal carried on silica in the presence of 500−10,000 p.p.m. S. The catalyst is prepared by impregnating SiO2 with an aqueous solution of, for example, RhCl3, Pd(NH3)2Cl2, H2IrCl6.6H2O, H2PtCl4.6H2O and dried finally at 371°C before being sulphided with n -hexane containing 1,000 p.p.m. S as dimethylsulphide.

Process and Apparatus for the Manufacture of Nitric Acid

humphreys & glasgow ltd British Patent 1,143,946

A process for the manufacture of HNO3 by the catalytic Pt oxidation of NH3 is performed at a gas-turbine operating pressure. The hot gases from the oxidation stage are expanded in a gas turbine to recover energy.

Hydrogenation Reactions and Catalyst

laporte chemicals ltd British Patent 1,146,437

A hydrogenation catalyst consists of one or more Pt metals deposited on a macroreticular ion exchange resin (e.g. Amberlyst XN–1005) having a surface area of at least 5 m2/g.

Esters of Unsaturated Alcohols

b.p. chemicals (u.k.) ltd British Patent 1,148,583

The catalyst for the vapour phase reaction of C2H4, air and CH3COOH to give vinyl acetate is periodically reactivated by heating the catalyst/support mixture in a liquid alkaline medium. The catalyst comprises a Pt-group metal (Pd) deposited on Al2O3, alumino-silicates, heavy metal oxides, metal oxide/Al2O3 complexes, C or pumice (preferably Al2O3).

Catalytic Reforming

universal oil products co. U.S. Patent 3,413,213

A catalyst for reforming gasoline feedstocks is prepared from purified Al2O3 by introducing 50−5,000 p.p.m. of an Fe compound and then impregnating with H2PtCl6 and calcining, the calcined product being sulphided.

Isomerisation of Saturated Hydrocarbons

universal oil products co. U.S. Patent 3,413,369

The isomerisation catalyst is a Group VIII metal, such as Pt, deposited on a refractory support such as Al2O3 which has been treated with AlF or SiF2 vapour at 650−1,200°C. See also 3,413,370−1.

Platinum-Rhenium Naphtha Reforming Catalyst

chevron research co. U.S. Patent 3,415,737

Naphtha free from S may be reformed using a catalyst consisting of 01.−3 wt% Pt and 0.01−5 wt% Re on a porous solid support.

Gas Purification by Hydrogenation

catalysts and chemicals inc. U.S. Patent 3,420,618

O2, C2H4 and C2H2 are removed from a H/CO feedstock by selective hydrogenation using a Pd/Al2O3 catalyst where the Pd content varies with the gas to be removed.

Sulphided Platinum Metal Catalyst

sinclair research inc. U.S. Patent 3,422,002

Hydrocarbons, (e.g. those boiling above 450°F), which contain N impurities are hydrofined using a catalyst consisting essentially of about 0.5−5 wt% of a Pt metal and about 4−30 wt% of MoO on Al2O3. The catalyst is presulphided. Hydrofining conditions include a temperature of about 400−800°F. When using Ru and Ir, temperatures of at least about 635°F are employed.


Hydrogenation Process

imperial chemical industries ltd British Patent 1,141,817

An organic substrate containing two or more sites of unsaturation is selectively homogeneously hydrogenated by contacting substrate with H2 in the presence of a solution containing as catalyst a divalent Ru compound (e.g. RuCl2(PPh3)3, RuHCl(PPh3)3 or RuCl2(AsEt2Ph)3) and arresting the reaction when the substrate has reached the required degree of hydrogenation. The catalyst may also contain a hydride e.g. LiAlH4.

Curable Organopolysiloxane Compositions

dow corning corp. British Patent 1,141,868

Organopolysiloxane compositions curable in the presence of Pt compounds (e.g. the reaction product of H2PtCl6 and a vinylated organopolysiloxane) are treated with an inhibitor (e.g. an acetylenic compound) so that the composition may be stored in the presence of the curing agent for considerable length of time without being cured.

Improvements in and Relating to the Production of Organic Isocyanates

imperial chemical industries ltd British Patent 1,142,991

An aliphatic or cycloaliphatic hydrocarbon or substituted hydrocarbon containing at least one -C = CH- group is reacted with isocyanate ions under substantially anhydrous conditions in the presence of a salt or co-ordinated compound of Pd (chloride). The inert solvent may be sulpholane or methylacetamide and there may be a redox system (CuCl2 or an Fe salt) present which is reoxidised by O2. In an example, KCNO + PdCl2 are heated to 90°C in sulpholane and octene −1 added. Metallic Pd is precipitated during the reaction.

Oligomerisation Process

geigy (u.k.) ltd British Patent 1,143,065

Butadiene oligomers are produced by heating butadiene in the presence of a catalyst consisting of RhCl3 reduced by reaction with a mixture of C2H5OH and acrylonitrile.

Preparation of Vinyl Esters of Carboxylic Acids

denki kagaku k.k.k. British Patent 1,146,791

The olefine-carboxylic acid reaction in the presence of O2 takes place using a liquid phase containing Pt metal or a Pt compound promoted with a vanadyl salt.

Oxidation of Aromatic Compounds

imperial chemical industries ltd British Patent 1,147,793

Phenols are produced by bringing into contact a liquid aromatic hydrocarbon or phenol with H2 and O2 in the presence of a redox system and a compound of a Group VIII metal (Pd, Ru, Rh, or Pt). The redox system may be an Fe carboxylate (acetate). In examples platinous chloride is the preferred noble metal compound.

Preparation of Aroyl Halides

national distillers and chemical corp. British Patent 1,149,359

An aroyl halide (benzoyl bromide or chloride) is prepared from an arylhalide containing at least one active H by reacting the latter with CO in the presence of a Pt- or Pd-triad catalyst. The catalyst may be palladous or platinous chloride or bromide.

Butadiene Chloride Copolymerisation Catalyst

p.p.g. industries inc. U.S. Patent 3,418,298

Copolymerisation of dichlorobutadiene is catalysed by active Ir, Rh or Ru compounds, such as a cyclooctadiene complex of Rh dichloride.

Platinum Metal Azo Complexes

massachusetts institute of technology U.S. Patent 3,424,739

Organometallic complexes useful as catalysts for the polymerisation of olefines are formed by reacting a Pt or Pd salt with an aromatic azo compound.


Catalyst for a Fuel Cell Electrode

american cyanamid co. British Patent 1,144,824

A catalyst for a fuel electrode (H2, CO) of a fuel cell comprises Rh, an amorphous W oxide (valency of W less than 6), Pt, and Mo oxide in specified proportions. It is produced by coprecipitation, from aqueous solution, to form an intimate mixture of an alkali metal borohydride, a Rh salt, a metatungstate, H2PtCl6 and a molybdate.

Catalytic Fuel Cell Electrodes

allis-chalmers mfg co. U.S. Patent 3,411,953

A catalytic electrode is produced by precipitation, using alkali metal hypophosphite, a flocculant Ni-Pd alloy from an aqueous ammonium solution, the alloy being shaped and made into the electrode in the usual way.


Separation of Hydrogen from Other Gases

international nickel ltd British Patent 1,147,010

H2 is separated from other gases by bringing the mixture into contact with a Pd sponge or the powder of a Pd-Ag-alloy consisting of at least 70% Pd and specified amounts of Au, Ag, B, Cu, Ni, Ru, Pt and/or Rh. Alternatively inert particles coated with Pd or with such an alloy may be used.


Apparatus for the Production of Glass Filaments

owens-corning fiberglass corp. British Patent 1,143,725

In the formation of glass filaments, molten glass is drawn from Pt or Pt-alloy orifices and cooled by means of Cu or Ag fin shields. The fin shields are plated with Ni so that contact of the fin shield with the hot Pt orifice does not cause contamination of the latter.

Vitreous Ceramics

matsushita electrical industrial co. U.S. Patent 3,421,916

Addition of 2−8 mol. % PtF2 to a glass composition produces a glass composition of good sinterability.


Method of Producing Semiconductor Devices Having Connecting Leads Attached thereto

sylvania electric products inc. British Patent 1,143,506

The body of a semiconductor material has conductive contacts (Pt silicide) in ohmic connection with its underlying portions. A first temporary layer of conducting material (e.g. Cu) leaves exposed areas on which the conducting leads are to be formed. Then a second layer (e.g. Ti and Pt) is laid over all and the first layer is etched away.

Cathodes for Electrical Discharge Vessels

siemens a.g. British Patent 1,143,865

The emissive substance carrier of a dispenser cathode is covered with a layer of at least one Pt metal, especially a metallic Os layer to reduce the escape energy of the cathode.

Electrodes for Electrolysis

h. b. beer British Patent 1,147,442

An electrode for an electrolytic process comprises a core of a film-forming metal (Ti, Ta, Zr, Nb and alloys) and a layer, the outside portion of which is resistant to electrolyte and electrolysis products and which consists of at least one oxide of a metal selected from Pt, Ir, Rh, Pd, Ru, Os and alloys formed between these metals. The entire layer may be formed of this material or only the outer portions of it.

Composition for Electrical Contacts

e. i. du pont de nemours & co. U.S. Patent 3,413,240

Fired on contacts for Pd-based electrical resistors are produced from (a ) a finely divided Pd, Pd oxide or Pd-Ag alloy, (b ) finely divided Ag and (c ) finely divided ceramic binder.

Palladium Copper Contact

western electric co. U.S. Patent 3,413,711

A metallic lead is soldered to a base of a metal other than Cu but having an affinity with Cu (e.g. a thin film Ta nitride circuit path) by depositing on the lead a layer of Cu of specified thickness, depositing a Pd layer over the Cu layer, applying solder to the lead and the Pd layer to dissolve the Pd and form a bond with the underlying Cu layer.

Metallising Compositions for Conductors and Condenser Electrodes

e. i. du pont de nemours & co. French Patent 1,536,249

The metallising composition consists of 75−95% finely divided noble metal (100 parts Ag, 0−100 parts Pd and 5–40 parts Pt) and 25−5% of a mineral binder e.g. Bi2O3 as a Cd or Na borosilicate glass.

Resistance Film Composition

johnson matthey & co. ltd French Patent 1,541,456

A metallising composition is proposed which produces a film on a non-conducting base whose resistance does not vary firing temperature. It consists of finely divided Ru oxide (preferably 10−80 wt%) or a Ru oxide/Group V metal oxide composition and glass (preferably 90−20 wt%) with optionally up to 10 wt% of a Group I or II metal oxide.



johnson matthey & co. ltd British Patent 1,148,305

A thermocouple has a positive element of a binary Pd-Pt alloy and a negative element of a binary Au-Pd alloy. Both alloys arc made by powder metallurgical methods. The percentage compositions of the alloys are within the ranges: positive element: Pd 80−90 wt%, Pt 10−20 wt%; negative element: Au 50−60 wt%, Pd 40−50 wt%.

Thermistor Manufacture

research corp. U.S. Patent 3,414,861

A thermistor is constructed of a Pt-wire with an enlarged bulbous head. This bulb is covered with thermistor material (NiO/CuO/Mn2O3) and this in turn, by a conductive film (e.g. of Pt) deposited by a sputtering process.

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