Platinum Metals Rev., 1968, 12, (4), 154
NEW PATENTS: October 1968
METALS AND ALLOYS
An Improved Alloy
johnson, matthey & co. ltd British Patent 1,112,766
A new alloy, especially suitable for spinnerette production, consists of 50−80% Au, 0.04−0.5% Ir, and the remainder Pt with the usual impurities.
Producing Iron-Rhodium Base Alloys Having Improved Magnetic Transition Properties
general electric co. (new york)
British Patent 1,117,727
An alloy with a CsCl-type ordered crystal structure and an antiferro-magnetic-ferromagnetic transition is obtained from an Fe-Rh alloy, optionally containing small amounts of Pd or Pt, by heat treating at a temperature above 800°C to produce homogenisation of the alloy and then quenching the alloy to a temperature below 800°C.
Treatment of Palladium and Palladium-base Alloys
johnson, matthey & co. ltd British Patent 1,117,739
British Patent 1,091,051 relates to a method of treating Pd or its alloys to reduce discontinuous yielding under stress. This method may now be applied to alloys in which Na has been added to suppress the formation of Pd silicide.
Production of Platinum and/or Palladium Oxides or their Mixtures with Rhodium, Iridium or Ruthenium Oxides
johnson, matthey & co. ltd German Patent 1,266,293
A composition comprising a powder of one or more of the above oxides is produced by the anodic oxidation of Pd, Pt or a suitable alloy with the other Pt metals in a molten mixture of an alkali metal nitrate or chloride.
deutsche gold- & silber-scheideanstalt German Patent 1,266,511
Methods are provided for the heat treatment of magnetic alloys containing Fe with 25−62 wt% Pd, produced by melting or sintering.
Improvement of Metal Properties
New Ruthenium Complexes
ste usines chimiques rhone-poulenc French Patent 1,503,334
On contacting RuCl3 or RuI3 with certain nitrile or olefine ligands, new complexes are formed of formula RuXmLn, where m is 2 or 3 and n is 4 or 3, X is halogen and L is an olefine activated by certain groups, an aromatic nitrile or a saturated aliphatic or cycloaliphatic nitrile.
ELECTRODEPOSITION AND SURFACE COATINGS
imperial metal industries (kynoch) ltd British Patent 1,113,421
A Ti core or a core of a similar metal is given a coating of another metal, especially Pt group metal, without first removing the oxide film. By definition Pt group metal excludes Pd but includes the other five metals. The Pt metal is applied in the form of an alloy with a very readily dissolved metal, such as Cu.
Deposition of Ruthenium
johnson, matthey & co. ltd British Patent 1,114,595
A porous base is impregnated with Ru (e.g. to produce Ru/Al2O3 catalysts) by contacting it with a solution of (NH3)6Ru(NO3)3, and then decomposing this compound to leave behind Ru metal.
i.b.m. corp. U.S. Patent 3,376,206
Catalytic films of high activity are deposited, especially on Cu and its alloys, by using baths containing water-soluble salts of Pd and strong acids, buffering salts of weak bases and strong acids and organic complexing agents at pH 4–5.5, e.g. PdCl2, NH4Cl and disodium EDTA.
Ceramic Metallising Paint
e. i. du pont de nemours & co. U.S. Patent 3,380,835
Successful metallising of ceramics with Pt group metals, e.g. Pt and Pd, is achieved by deactivating these catalytic powders previously by heating or by treatment with As oxide, Sb oxide, etc.
Chemical Platinum Plating Process
johnson, matthey & co. ltd French Patent 1,512,175
PtO2, alone or mixed with up to 50% of another Pt metal oxide, is reacted with a 2–5 C aliphatic alcohol to give a dispersion. The dispersion is contacted with a substrate in the presence of H2O and a H2O soluble mineral acid to deposit Pt (or Pt alloy) on the substrate. The deposit is dried and organic material eliminated.
Applying Designs to Metallic Bases
johnson, matthey & co. ltd Canadian Patent 785,472
A metal or alloy differing in colour from the metal base is applied in an organic base and fired to produce slight adherence, the metal or alloy then being embossed with a design. Au, Ag and Pt metals, e.g. in flake form, are suitable decorative materials. This corresponds to French Patent 1,455,917 and Italian Patent 767,740.
High Temperature Brazing Alloys
Epitactic Ruthenium Catalyst
e. i. du pont de nemours & co. British Patent 1,113,405
The “epitactic” catalyst is a support of eta-Al2O3 carrying an epitaxial growth of Ru. It is produced from RuCl3 or nitrosonitrate solution which is adjusted to pH 3.5–4.5 with (NH4)2CO3 or NH4HCO3 and then mixed with a slurry of solid eta-Al2O3 particles. Further alkali is added to bring the pH to 7.5–8.5 while heating at 45−85°C. After 20 min the precipitate is removed, dried and treated with H2.
Production of 2,3-Dimethyl Butane
universal oil products co. British Patent 1,115,176
The isomerisation to 2,3-dimethyl butane of neo-hexane is catalysed at 100−500°C and 1–150 atm by a Group VIB or VIII metal on an acidic support, e.g. Pt/Al2O3 with small amounts of F2 and Cl2. For the highest yield, the rate of flow of the neohexane should be such that 0.1−20 mol% of it is converted in each pass.
Catalytic Reactions and Catalyst
johnson, matthey & co. ltd British Patent 1,116,943
An improved catalyst for the isomerisation of olefines, especially 1-C5H10 is obtained by absorbing a catalytically active Pt group metal on to a solid porous support from a thermally stable solvent, e.g. using RhCl3.3H2O in ethylene glycol.
Catalytic Cracking of Hydrocarbons
w. r. grace & co. British Patent 1,117,210
The catalyst consists of 0.1−2 wt% Pd, Rh and/or Pt deposited on a SiO2-Al2O3-zeolite support. The support contains 10−40% uncombined Al2O3 and 5−80% of a zeolite of formula xM2/nO.Al2O3.3.5–7SiO2.0–9H2O, where M is a cation of valency n and x is 0–1. 1,117,209 describes the same catalyst supports used for Co and Ni catalysts.
catalysts & chemicals inc. British Patent 1,120,307
Small amounts of C2H2 in C2H4 are selectively hydrogenated by adding an excess of H2 and passing the gas mixture over a supported Pd catalyst in the usual way. The selectivity is improved by adding 5–400 ppm of CO to the olefin.
Platinum Gauze Catalyst Activation
monsanto co. U.S. Patent 3,371,989
The reaction over a Pt gauze of NH3, natural gas and air to give HCN is improved by flowing the reactants over the gauze at 1.28–1.45 lb/hr/layer of gauze/in2 in order to activate the catalyst.
Aluminosilicates Containing Platinum Metals
mobil oil corp. U.S. Patent 3,373,110
Pt metal impregnation of a synthetic zeolite is achieved by adding a Pt metal salt solution (especially containing a Pt or Pd salt) to the aluminate and silicate solutions from which the zeolite is formed.
Selective Hydrogenation Catalyst
farbenfabriken bayer a.g. U.S. Patent 3,373,219
The selective hydrogenation of 4C acetylenic compound in a mainly butadiene fraction is improved when the fixed Pd catalyst is supported on a Li Al spinel.
High Octane Petrols
air products & chemicals inc. U.S. Patent 3,374,167
A full range reformate is hydrogenatively reformed over Pt/Al2O3, a heart cut is removed from the product and this cut is again hydrogenatively reformed over Pt/Al2O3. Less catalyst deactivation occurs.
universal oil products co. U.S. Patent 3,377,269
The particles of catalyst are based on Al2O3 with a variable density of catalyst where a small part of the total surface has small localised spots of Pt with a high density of 10,000–20,000 μg/m2 Pt and the remainder of the surface has a low density of the order of 0.9–10 μg/m2 Pt, giving a total Pt content of 0.05−0.2 wt%. The catalyst can be used for burning I.C.E. exhaust gases.
Oxidisation of Waste Gases over Mixed Catalysts
universal oil products co. U.S. Patent 3,378,334
Combustible gases (e.g. I.C.E. exhaust gases) are mixed with O2 and passed over a fixed bed of spherical Pt catalyst particles, some of the particles (8−30%) having a Pt content up to about 5% and the remainder a low Pt content so that the overall content is 0.05−0.2 wt%.
toa nenryo k.k.k. U.S. Patent 3,378,590
The production of aldehydes and alcohols from olefins, H2 and CO is catalysed by Co promoted with Pd/C or Pt/C.
Gas Reactions Using Gauze Catalysts
montecatini-edison s. p.a. U.S. Patent 3,379,500
Specific mixtures of NH3, CH4, N2 and O2 are reacted over gauze catalysts made of Pt or its alloys at 1100−1200°C.
Low Pressure Platinum Reforming Catalyst
universal oil products co. U.S. Patent 3,379,641
Low pressure reforming is catalysed by a sulphided Pt-Fe-halogen/Al2O3 catalyst having an Fe content of 100–1000 ppm, uniformly distributed throughout the catalyst.
Hydrogenation of Olefine Polymers in Cumene
gulf oil corp. U.S. Patent 3,379,767
Cumene contaminated with olefin polymers is passed over a Pd/Al2O3 catalyst in a fixed bed at 100−300°F in the presence of H2 to hydrogenate the olefin polymers.
Oxidation of Glucose
johnson, matthey & co. ltd Dutch Appln 67.13,891
Selective oxidation is achieved using a supported Pt metal catalyst (e.g. Pd) in the presence of Na or K carbonate or bicarbonate.
imperial chemical industries ltd British Patent 1,111,714
Vinyl or allyl alkyl ethers are produced by contacting a vinyl or allyl ester of an aliphatic car-boxylic acid with a 1–20 C aliphatic alcohol in the presence of an organic solvent containing 0−10% H2O and a salt or coordination compound of a Pt metal, especially Pd, Pt, Rh and Ru. Typical catalysts are Li2PdCl4 and Pd(OOC.CH3)2.
Producing Vinyl Acetate
asahi kasei k.k.k. British Patent 1,116,588
The reaction of C2H4 and O2 in the presence of a chloroacetic acid to give vinyl acetate is catalysed by oxides, hydroxides and salts (readily reacting with acetic acid to give acetates) of Pt, Pd, Ru, Rh or Ir promoted with Cu, Ag, Cd, Sn, Pb, Cr, Mo, W, Fe, Co or Ni.
Manufacture of Vinyl Esters
courtaulds ltd British Patent 1,116,945
The oxidation of C2H4 in the presence of a carboxylic acid to form a vinyl ester is catalysed by a circulating liquid solution of a palladous carboxylate, a metal salt able to oxidise Pd metal and an alkali metal carboxylate. The reaction yields Pd metal as a by-product and this is heated with a carboxylic per-acid to regenerate the palladous carboxylate.
Production of Vinyl Carboxylic Esters
celanese corp. British Patent 1,121,103
A vinyl ester of a 2–7 C aliphatic acid is produced from C2H4, the 2–7 C acid and O2 in the presence of halogen, cupric, Pd and 2–7 C acid ions, the Pd and Cu being present in at least 0.002 and 0.2 M concentrations respectively.
Olefin Oxidative Carbonylation
union oil co. of california U.S. Patent 3,381,030
Olefins, O2 and CO2 react to give unsaturated carboxylic acids and aliphatic esters in the presence of an anhydrous organic solvent solution containing 0.01−5 wt% Group VIII metal, especially Pd, in a redox system at 30−300°C and at an elevated pressure.
Olefine Polymerisation Catalysts
institut francais du petrole, des carburants et lubrifiants French Patent 1,505,335
The specificity and activity of Ziegler catalysts is improved by the introduction of a Group VIII noble metal salt or complex, preferably a complex produced in situ. Thus a complex of PdCl2 and PPh3 can be formed in the presence of Et2AlCl and TiCl3.
Production of Fumaric Acid and Muconic Acid Dichlorides
badische anilin- & soda-fabrik a.g. German Patent 1,263,752
The reaction of C2H2, CO and PH3 is catalysed by 0.001−5 wt% of Pd or a Pd compound at 50−120°C and 50–300 atm gauge.
Production of Alken-2-yl-1-ethers
consortium für elektrochemische industrie g.m.b.h. German Patent 1,269,613
The production of these ethers by the reaction of the corresponding halides with alcohols is catalysed by Group VIII noble metals, especially Pd and Rh halides or halide complexes, e.g. Na2PdCl4.
In Situ Preparation of Hydrogen and Simultaneous Hydrogen Control in Electrochemical Cells
protech inc. British Patent 1,114,851
H2 utilisation in a fuel cell is controlled by using an anode structure coated with a layer containing Pd, (e.g. a Pd-Ag alloy) permeable only to H2.
Ion Exchange Membrane Electrode
general electric co. (new york)
British Patent 1,120,267
Electrodes particularly suitable for fuel cells are produced by electrolytically depositing a thin layer of catalytically active noble metal (especially Pt) on a conducting base, washing and drying the deposit and finally transferring the deposit by physical contact to the surface of an ion exchange membrane. Pt alloy deposits may be produced and transferred in the same way.
Platinum-coated Fuel Cell Electrode
texaco inc. U.S. Patent 3,377,204
A porous C electrode is treated to incorporate Pt by heating the electrode in CO2 at 700−1000°C for 1–10 hours, coating the electrode surface with H2PtCl6, reducing the acid to Pt metal at 200−300°C for 1–4 h in a H2 atmosphere and finally heating the electrode at 700−1000°C for 1–10 h in a H2 atmosphere.
Vapour Diffusion Fuel Cell Electrode
monsanto research corp. U.S. Patent 3,382,103
N2H4 is supplied to the fuel cell anode through a three-layer barrier of which the central layer contains a N2H4 decomposition catalyst such as Ru or Rh.
Fuel Cell Electrode Assembly
u.s. national aeronautics & space administration U.S. Patent 3,382,105
The electrode assembly consists of thin plastic ion exchange membranes coated with finely divided Pt catalyst.
Electrodes with Activated Platinum Group Coatings
oronzio de nora implianti electrochimici British Patent 1,111,767
An electrode for impressed current cathodic protection has a solid base (e.g. of Ti) coated with a Pt metal containing 0.2−2 wt% of Sb, Cd, Pb, Cu, Ta, V, Nb or their mixtures as activating element. Preferably a coating of Pt containing Sb is applied to a Ti base.
ELECTRICAL AND ELECTRONIC ENGINEERING
Cermet Resistance Element
Resistive Elements for Variable Resistors
amphenol corp. British Patent 1,114,052
Low noise characteristics are obtained by coating an insulating base with a Ni-Cr-Fe alloy and applying a film of Pt, Rh or Ir.
Materials for an Electric Contact
hitachi ltd British Patent 1,116,788
Electrical contacts are made from Pd containing 0.1−10 wt% of a Pb compound or compounds. Preferably 0.1−10 wt% of PbS and/or PbO are introduced into Pd by sintering or by addition to molten Pd.
Metal Glaze Resistance
international business machines corp. U.S. Patent 3,372,058
Resistances are produced on ceramic dielectrics by applying and firing a glaze containing 15–70% PdO or RhO, having a crystallite size with a surface area of at least 0.75 m2/g, and up to 35% of a conductive metal, such as Ag, dispersed in 35−70% vitreous enamel frit.
Conductive Noble Metal Paint
international business machines corp. U.S. Patent 3,374,110
An alloy of 75−85% Ag and 25−15% Pd is produced and powdered for use with a ceramic frit to give a conductive paint. This alloy, unlike pure Ag, does not migrate and can be soldered.
Piezoelectric Lead Zirconate Titanate
nippon electric co. ltd U.S. Patent 3,375,194
The electromechanical coupling and mechanical qualities of these ceramics are improved by incorporating 0.01−1.0 wt% of Rh2O3.
Sintered Palladium Electrical Contacts
hitachi ltd U.S. Patent 3,380,812
Electrical contacts for use in an organic gas atmosphere are made from Pd with an added inorganic Pb compound, e.g. litharge, to reduce its catalytic action and thus eliminate the formation of brown deposits when operating in organic gases.
High Temperature Thermocouples
Improved Vessel for Molten Metals
yawata iron & steel co. ltd British Patent 1,117,935
In order to make measurements on molten metals, the vessel is fitted with a standard electrode for measuring the O2 content electrochemically. The standard electrode is also matched with a metal wire, e.g. a Pt-Rh wire, to act also as part of a thermocouple to measure the temperature.