Platinum Metals Rev., 1984, 28, (1), 39
NEW PATENTS: January 1984
METALS AND ALLOYS
Multilayered Amorphous Alloy
tokyo shibaura denki k.k. European Appl. 90,973
Multiple layers are produced by feeding a sequence of molten metals or alloys on to the surface of a roll rotating at high speed so that the metal solidifies. In one example one of the layers consists of Pd alloyed with 20% Si. The alloy structures may be used for superconductors, springs and latch relays.
Electrical Contact Alloy
ELECTROCHEMISTRY
Electrolytic Cell Electrodes
imi marston ltd. British Appl. 2,113,718A
A cell such as a hypochlorite cell is operated with one anode consisting of a Ti base coated with platinum group metal and two cathodes made of TiOx. One cathode is used while the other is being cleaned by local acid generation.
Corrosion Protection Anode
oronzio de nora impianti elettrochimici s.p.a.
European Appl. 84,875
Platinum group metal-coated valve metal anode elements are used in a new design of linear anode structure for cathodic protection.
Catalytic Electrodes
diamond shamrock corp. European Appls. 87,185/6
Electrodes for use in the electrowinning of Zn, Cu or Co are made by impregnating a Ti sponge with a catalytic mixture of TiO2, Ru oxide and optionally Pd oxide and fixing the product to a Pb support.
Modified Electrodes
ajinomoto co. inc. European Appl. 88,592
Electrodes having a wide variety of potential uses consist of an electrically conducting solid, such as Pt, on the surface of which are immobilised a strongly acidic cation exchange resin containing aromatic groups, such as a poly (styrene sulphonic acid) and a N-containing electron mediator such as a viologen or a complex of Os, Ru or Fe with phenanthroline or bipyridine.
Composite Electrolysis Electrode
ishifuku metal industry co. ltd.
European Appl. 90,425
An electrode with a low overvoltage and high durability is obtained using a conventional body of Ti, which is coated with a layer of porous Pt. The porous layer is permeated with Ru, Ir and/or Pd which is then converted to oxide.
Electrochemical Vinyl Acetate Production
celanese corp. U.S. Patent 4,383,899
Ethylene and acetic acid are reacted at a Pd anode to give vinyl acetate using a potential of 0.4–1.8 V.
Photoelectric Cell
matsushita electric industrial co. ltd.
U.S. Patent 4,388,385
A cell is claimed which consists of a transparent electrode, made of Sn oxide or vacuum-deposited Pd, Pt or Au, a solid electrolyte which is AgBr, AgI or a complex salt such as RbAg4I5 and a second electrode capable of forming a charge-transfer complex with halogen, such as a polyvinyl pyridine.
Hydrogen Diffusion Membranes
ELECTRODEPOSITION AND SURFACE COATINGS
Polymer Coating Method
national research development corp.
British Appl. 2,117,669A
A new technique is used to produce very thin, highly ordered polymeric films on substrates. The substrates listed include Pt, Au, Ag and superconducting alloys containing platinum group metals.
Electroless Plating
a/s neselco European Appl. 87,135
An improved catalyst which removes the need for pre-etching a plastics substrate prior to electroless plating consists of a finely powdered plastics material such as a styrene-acrylate copolymer, impregnated with an ester surfactant, Sn chloride, Pd chloride.
Electric Terminals
a.m.p. inc. European Appl. 91,209
Terminals are selectively plated with Pt, Pd, Au, Ag or their alloys as they are wrapped round a mandrel.
Palladium Electroplating Bath
siemens a.g. German Offen. 3,148,788
Uniform bright deposits are obtained from a bath containing per litre, 10–100 ml phosphoric acid of density 1.71 neutralised with 25% aqueous NH3 and 5–40g Pd as Pd chloride at pH 6.5–8.5.
Palladium Electroplating Solution
v. a. kirilov and a. d. kisbyachuk
Russian Patent 1,006,549
Bright deposits are obtained from an electroplating solution containing, per litre, 10–40g Pd chloride, 20–40g ammonium sulphate, 80–160g monoethanolamine (97%), 0.5–1.5g long-chain aliphatic alcohol and 0.3-1g hexamethylenediamine tetraacetic- or diethylenetriamine pentaacetic acid.
LABORATORY APPARATUS AND TECHNIQUE
Moisture-Responsive Electrical Element
sharp k.k. British Appl. 2,113,400A
A moisture-responsive element is a membrane of an organic polymer having a hydrophilic group sandwiched between electrodes of Ru, Pt or Au.
Electrochemical Chlorine Sensor
centre national de la recherche scientifique
British Appl. 2,117,121A
The measuring electrode of a sensor is formed from a compound of Ru, Ir, Os, Mo or W which is conductive at room temperature. The preferred compound is RuO2 and/or RuCl3.
Gas Detection Device
hitachi ltd. European Appl. 84,935
CO is detected as distinct from H2 through the absence of a polarisation current in a cell. The cell has electrodes of Pt or Pd in a fluorocarbon binder.
Membrane Electrode for Non-Ionic Species
university patents inc. European Appl. 85,704
Non-ionic species in aqueous media, such as glucose in blood, is monitored by a membrane electrode consisting of a polymer matrix containing a water-insoluble salt of the non-ionic species deposited on a conductor such as Pt, Au, Ag or C.
Measuring Probe
rheometron a.g. European Appl. 87,425
A measuring probe for inductive magnetic flowmeters consists of a Pt wire electrode around which is sintered a tube of oxide ceramic such as Al2O3. Leads are provided on the outside of the tube by means of a conductive ink containing Pt particles.
Exhaust Gas Oxygen Sensor
hitachi ltd. European Appl. 89,630
A sensor using the Pt-ZrO2-Y2O3 system employs O2 in the atmosphere to supply an independent control for the measurements.
Oxygen Sensor
JOINING
HETEROGENEOUS CATALYSIS
Alkyl Tertiary Amine Production
mitsubishi petrochemical co. ltd.
British Appl. 2,113,210A
Tertiary amines may be produced with catalyst reuse by reacting CO, H2 and a primary or secondary amine in the presence of a Rh and/or Ru catalyst and an alcohol solvent. The alcohol is chosen so that the amine separates from a phase containing the catalyst in water such as Rh chloride.
Catalyst and Process for Ammonia Oxidation
johnson matthey p.l.c. British Appl. 2,114,461A
A typical Haber process catalyst containing Fe which may be derived from magnetite, is promoted with a mixture of La and Ni in a 1 : 4−6 ratio and optionally with Ru, Co or Ce. A typical combination is LaNi5 with 20% Ru.
Zeolite Dehydrocyclisation Catalyst
chevron research co. British Appl. 2,116,450A
The dehydrocyclisation of acyclic hydrocarbons to aromatics is achieved at a higher conversion rate using a catalyst consisting of an L type zeolite, Ba, Sr or Ca and a Group VIII metal, preferably Pt. Typically 0.1−35% Ba and 0.1−5% Pt are present.
Platinum Wire Catalysts
alloy surfaces co. inc. British Appl. 2,117,400 A
Pt wire containing 0.5−5% Al is formed by thermal diffusion of the Al. The Al is then leached out to give a “Raney” structure which is heated at 1800−2300°F for at least one week to give catalytic stability, a longer active life and a surface which fissures less. The Pt may be alloyed with another platinum group metal.
Oxygenic Compound Production
hoechst a.g. European Appl. 85,398
Acetic acid, acetaldehyde and ethanol are produced by the reaction of CO and H2 in the presence of Rh promoted with an element or elements of atomic number 21, 39 and 58–71, such as a lanthanide. The catalyst may be supported. In the examples Rh/SiO2 is promoted by La, Ce, Y, Ho or Gd.
Exhaust Catalyst
u.o.p. inc. European Appl. 87,808
A catalyst for the oxidation of exhaust gases from I.C. engines or organic processes consists of a metal substrate such as a Ni-Cr alloy electroplated with 0.1−1% Pt or Pd and 0.1−1% Ce or La.
Hydrogenation Process
sumitomo chemical co. ltd. European Appl. 87,980
In a process for the selective hydrogenation of specified unsaturated hydrocarbons in mixtures over a fixed bed of Pt-supported catalyst, the H2 is introduced at more than one point along the length of the reaction vessel.
Removal of Hydrogen from Gases
cjb developments ltd. and universal matthey products ltd. European Appl. 89,183
H2 is removed from a gas which also contains O2 by contact in the cold with a catalyst containing 0.25−2.5% Pd on a Sn oxide-Al2O3 support. The process is particularly useful for the removal of H2 from wet air in enclosed spaces. A third Group VIII metal may also be present in the catalyst.
Disposable Anaerobic Catalyst
johnson matthey p.l.c. European Appl. 89,830
In a process for reacting traces of O2 in anaerobic jars with H2, a catalyst comprising Pd, Pt, Rh and/or Ir on a porous C support is used. The preferred catalyst is 1.67−2.29% Pd/C fibre cloth. This catalyst does not produce fines and so reduces the likelihood of an explosion in the H2/O2 mixture. The catalyst may be used once and then disposed of.
Olefin Production from Methanol
basf a.g. European Appl. 90,232
Olefins have been produced from methanol and/or dimethyl ether in the presence of zeolite catalysts. The olefins are now produced in a multiple stage process where the residual reaction product (after olefin separation) is hydrogenated and cracked to give 2–4C olefins. The hydrogenation of the residue may be catalysed by Pt/ or Pd/Al2O3.
Reforming Catalyst
exxon research & engineering co.
U.S. Patent 4,379,076
A catalyst for hydrocarbon reforming consists of an Al2O3 carrier impregnated with 0.1−2% Pt, 0.1−2% Ir, 0.01−0.1% Cu, 0.001−3% S and 0.1−2.5% halogen.
Reactivating Acyloxylation Catalysts
basf a.g. U.S. Patent 4,379,756
Supported Pd-Cu-Te catalysts used for the acyloxylation of butadiene are reactivated by heating them at 200−900°C in an inert gas such as Ar.
Hydrogen Peroxide Production
air products & chemicals inc.
U.S. Patent 4,379,778
Improved reduced catalysts for the combination of H2 and O2 to give peroxide are obtained when Pd is deposited on a C support and then treated with an aldehyde or ketone and hydrochloric acid.
Catalysts for I.C.E. Exhaust Systems
general motors corp. U.S. Patent 4,380,510
A catalyst for the purification of I.C.E. exhaust is made by modifying a particulate Al2O3 carrier with one or more base metals, preferably chosen from Ce, La, U, Sn, Ba, Fe, Cu, Co and Ni, and then coating with thin layers of two platinum group metals preferably chosen from Pt, Pd and Rh.
Dehydrogenation Catalyst
u.o.p. inc. U.S. Patent 4,381,257
A catalyst for the dehydrogenation especially of paraffins or alkyl benzenes consists of an Al2O3 carrier impregnated with 0.01−2% Pt, 0.05−5% Co, 0.01−5% Ta and 0.1−5% Li or K oxide.
Shell Boilers
johnson matthey & co. ltd. U.S. Patent 4,384,549
Boilers, especially shell boilers, are provided with a catalyst to bring about the catalytic combustion of at least a proportion of any unburned fuel leaving the combustion chamber. The catalyst is preferably a substrate coated with a layer of refractory metal oxide and then with a platinum group metal or alloy. The use of the catalyst enables the boiler to be run more efficiently and reduces the time needed to clean the pipes of the boiler.
Hydrogenation Catalyst
exxon research & engineering co.
U.S. Patent 4,387,258
The selective hydrogenation of alkynes and dienes to alkenes is catalysed by a crystalline SiO2 polymorph of specified physical properties impregnated with 0.1−0.5% Pd.
Oxidation Catalyst
american cyanamid co. U.S. Patent 4,389,386
A catalyst for the oxidation of HCN to isocyanic acid is Ag crystals coated with 20−10,000 ppm Pd.
Reforming Catalyst
basf a.g. German Offen. 3,201,457
A catalyst for the steam reforming of hydrocarbons to olefins consists of a carrier such as SiO2, promoted with Mg oxide, supporting Ru.
Hydrogenation Catalyst
HOMOGENEOUS CATALYSIS
Chiral Phosphines for Hydrogenation Reactions
f. hoffmann-la roche & co. a.g.
British Appl. 2,114,134 A
New chiral phosphines are (phosphino)(phosphinomethyl)pyrrolidines with the N atom optionally substituted, such as (2S,4S)-4-(diphenylphosphino)-2-[(diphenylphosphino)methyl]-1-(diphenylphosphinyl)pyrrolidine. Their complexes with Rh are asymmetric hydrogenation catalysts.
Aromatic Reduction of Cyclohexene
imperial chemical industries p.l.c.
British Appl. 2,114,149 A
A compound containing a cyclohexene ring is obtained by adding two nucleophiles and then two electrophiles to a dicationic organic Group VIII metal complex. The complex is preferably obtained from Ru, Rh or Ir, such as (hexahaptohexamethylbenzene)(pentahaptopentamethylcyclopentadienyl) ruthenium bis(tetrafluoroborate).
Ethylene Glycol from Synthesis Gas
texaco development corp.
British Appl. 2,114,562 A
Ethylene glycol and lower alcohols are produced by contacting CO and H2 with a Ru-containing compound, a substituted aromatic compound and a quaternary phosphonium bromide. Typical examples of the catalyst components are RuO2 or Ru carbonyl, chlorobenzene or hexamethyl benzene and tetrabutylphosphonium bromide.
Ethanol and Propanol Production
ruhrchemie a.g. European Appl. 84,833
Ethanol and propanol are produced by the reaction of methanol, CO and H2 in a reaction medium containing a Co compound, a Ru compound, an iodide and a phosphine. Ru acetylacetonate is used in some examples with Co carbonyl and Nal.
Rhodium Complex Catalysts
plurichemie anstalt European Appl. 86,046
In specified homogeneous hydrogenation reactions the catalyst system consists of triphenylphosphine, and a product of the reaction of hydrazine with a Rh complex, preferably RhCl(PPh3)3.
Rhodium Oxo Reaction Catalysts
toa nenryo kogyo k.k. European Appl. 89,697
New catalysts for oxo reactions, hydrogenation, isomerisation, etc., have the formula HRh(CO)(XAr3)n(YAr′3)3−n where X is P and Y is As or Sb, X is As and Y is P or Sb, or X is Sb and Y is P, As or Sb, n is 1 or 2 and Ar and Ar′ are aryl groups such as HRh(CO)(AsPh3)2(SbPh3).
Methanol Carbonylation Catalyst
shell internationale research mij. b.v.
European Appl. 90,443
The reaction of methanol with CO in the presence of CH3I and NaI to give acetic acid and/or methyl acetate is catalysed by Pd acetate and an amine ligand such as bipyridine or tetramethyl ethylenediamine.
Epoxide Polymerisation Catalysts
shell internationale research mij. b.v.
European Appls. 90,444/45
Catalysts for epoxide polymerisation are complexes of general formula Ma[M′(CN)bXc]d.wM″X′exH2O.yL.zHnX″m, where M′ and M″ may each be Ir, Rh or Ru, among others.
Catalytic Reduction of Nitroaromatics
montedison s.p.a. European Appl. 91,383
A nitroaromatic compound is reduced by the transfer of H from an alcohol in the presence of an Ir catalyst formed by an Ir salt chelated with an olefin or diene and a nitrogenous ligand such as an ethylene and dipyridyl complex of IrCl.
Aldehyde Ethers
davy mckee (oil & chemicals) ltd.
U.S. Patent 4,383,125
Aldehyde ethers useful in organic synthesis are obtained by hydroformylating the corresponding allyl ethers in the presence of a Rh catalyst such as HRh(CO)(PPh3)3.
Hydroformylation Catalyst
occidental research corp. U.S. Patent 4,386,013
A catalyst for olefin hydroformylation consists of a Rh compound or complex, such as Rh(CO)Cl(PPh3)2, intercalated on a carrier which is a layered Zr phosphonate complex such as (EtPO3)4Zr3{O3P(CH2)3PPh2}2.
Ester Production Catalysts
e.i.du pont de nemours & co. U.S. Patent 4,386,217
The formation of esters from olefins, alcohols, CO and O2 is catalysed by a system consisting of a heteropolyacid and a Pd compound or complex, preferably bis (benzonitrile)Pd dichloride.
Water Gas Reaction Catalysts
FUEL CELLS
Platinum Alloy Catalysts
united technologies corp.
British Appl. 2,117,791 A
The performance of Pt and other noble metal catalysts in reactions where the reduction of O is a rate limiting step is improved by increasing the electron density of states at the Fermi level of the catalyst. This may be achieved by alloying with suitable metals such as W, V, Mo, Co and Cr. The catalysts are useful for fuel cells and other purposes such as I.C.E. exhaust gas purification.
Fuel Cell with Catalyst/Oxidiser Electrode
hitachi ltd. European Appl. 90,358
Water-repellent particles and platinum group metal particles are supported on one side of an ion exchange membrane to provide an oxidiser electrode while other platinum group metal particles are placed on the opposite side of the membrane to form the fuel electrode, giving a three-phase system.
Fuel Cell Catalytic Electrode for Metals Recovery
exxon research & engineering co.
U.S. Patent 4,385,970
Platinum group metals, Cu, Ag and Hg may be recovered from acidic solutions in a cell in which the cathode is an electrically conductive porous substrate coated on its exterior surface with a fuel activating catalyst and fed with H2 in the absence of any externally applied potential. The catalyst is preferably Rh, Pt, Pd or Ir or an alloy or mixture of these metals.
CHEMICAL TECHNOLOGY
Platinum Metal Compounds in Photographic Materials
konishiroku photo industry co. ltd.
European Appl. 91,788
Ag halide photographic materials are given improved gradation characteristics by adding, based on 100g Ag, at least 40 mg of a water soluble Group VIII compound having a molecular weight of at least 100. Typical compounds are Na, K and ammonium chloropalladates, chloroiridates and chloroplatinates and RhCl3.
ELECTRICAL AND ELECTRONIC ENGINEERING
Magnetic Regenerative Wheel
u.s. department of energy
British Appl. 2,113,371 A
Cooling over a large temperature range is achieved using a wheel with layers of ferromagnetic or paramagnetic porous material arranged according to their Curie temperature. The preferred materials are gadolinium intermetallics, some with platinum group metals, such as Gd5Pd2.
Electron Tube Cathode Composition
hitachi ltd. British Appl. 2,116,356 A
An impregnated cathode capable of operation at lower temperatures consists of Os, Ru, Ir, W, Mo, Ta or Re powder mixed with Sc oxide and/or a mixed oxide containing Sc such as (Sc, Y)2O3. The emissive impregnant is Ba oxide.
Ruthenium Dioxide Resistors
corning glass works European Appl. 86,077
Frits which can be readily applied to Al2O3 to give films with a temperature coefficient of resistance of less than 100ppm are based on 32−39% PbO, 44−47% B2O3, 14−17% SiO2 and up to 5% WO3 or MoO3. These frits are used with RuO2 and a vehicle to give inks for resistor production.
Thin Film Magnet
hitachi ltd. European Appl. 87,559
A thin film permanent magnet is made by sputtering from a Co alloy containing 5−35 at.% Pt.
Electric Contact
siemens a.g. European Appl. 88,220
A non-sticking contact of low contact resistance consists of a ferromagnetic substrate tipped with Ag coated with a 0.2−2μ m film of Rh.
Electrographic Method of Circuit Board Production
eastman kodak co. European Appl. 89,221
A toner containing a chemical plating catalyst in its particles is used to produce a conductive circuit on a board by photocopying. The toner particles are fused and then reinforced by chemical plating. Platinum group metals and Au are among the catalysts which may be used.
Improved Liquid Connector
johnson matthey p.l.c. European Appl. 89,829
An electrical connection using a liquid conductive material, especially for use in glass fibre spinning, is designed to reduce stress between the parts. In a glass fibre spinning machine the bushing and the lug connecting it to a source of heating current may be made from platinum group metals, Ag, Au, Cu, Al or an alloy thereof. This improved electrical connector has a reduced tendency for the liquid conductive material to be expelled.
Information Storage
thomson-c.s.f. European Appl. 89,874
In an optical disc for information storage the sensitive layer is protected from the effects of atmospheric humidity by a transparent flexible barrier layer which is a thin film of Pt, Pd, Au or alloy thereof.
Integrated Circuits
burroughs corp. U.S. Patent 4,381,215
A method for forming electrical contacts to semiconductor chips includes the provision of successive layers of Pt silicide, a barrier metal preferably Ti-W and a conductor preferably Al.
Thick Film Conductor
e.i.dupont de nemours & co. U.S. Patent 4,381,945
The adhesion of a thick film conductor printing composition containing 30−80% finely divided Pd, Ag and optionally Pt, 1−20% Pb-Ge glass and 0.1−10% of a metal oxide capable of reacting with Al2O3 to form a spinel is improved by incorporating a hydrolysible Ti complex such as the acetylacetonate.
MOS Field Effect Transistor
texas instruments inc. U.S. Patent 4,384,301
The transistor has enhanced oxide thickness at the edge of the gate electrode, and Pt silicide regions in the gate electrode, and source and drain areas to improve the breakdown voltage in multilevel interconnect devices.
Semiconductor Devices
bell telephone laboratories inc.
U.S. Patent 4,388,383
In semiconductor devices based on InP, GaP or InGaAsP carrier recombination is suppressed by providing the surfaces with a monolayer or less of Rh, Au or Ag.
Printed Circuit Boards
robert bosch g.m.b.h. German Offen. 3,145,584
A conductive paste is applied to the surface of through-holes in printed circuit boards by means of an elastically deformable die. The board may be of ceramic or enamelled steel printed with a Ag-Pd paste and baked at 800−900°C, or a plastics substrate printed with a Ag paste and baked at 150−250°C.
Modified Titanium Dioxide
MEDICAL USES
Eyeless Suture Needle
m. seisakusho British Appl. 2,113,588 A
The blunt end of a needle blank made of oxidation resistant material is pierced with a heat resisting tool after it has been heated to near its melting point. Os and Ru may be used to produce the tool.
Pacemaker Electrode
w. c. heraeus g.m.b.h. European Appl. 85,743
In a specified cardiac pacemaker electrode, the lead consists of sintered particles of an Ir alloy such as 90% Pt−10% Ir.