Abstract: Magnesium alloys containing: Y: 2.0-6.0% by weight Nd: 0-4.0% by weight Gd: 0-5.5% by weight Dy: 0-5.5% by weight Er: 0-5.5% by weight Zr: 0.05-1.0% by weight Zn+Mn: <0.11% by weight, optionally other rare earths and heavy rare earths, the balance being magnesium and incidental impurities and the total content of Gd, Dy and Er is in the range of 0.3-12% by weight, wherein either the alloy contains low amounts of Yb and Sm and exhibits a corrosion rate as measured according to ASTM B117 of less than 30 Mpy, and/or the area percentage of any precipitated particles arising when the alloy is processed having an average particle size greater than 1 m and less than 15 m is less than 3%.

Abstract: An improved method for the formation of composite hydroxides or oxides comprising, on an oxide basis, Al2O3 and ZrO2, and optionally CeO2, La2O3, Nd2O3, Pr6O11, Sm2O3, Y2O3, and other rare earth oxides, comprising the steps of preparing an aqueous metal salt solution and forming a hydroxide precipitate slurry by combining the aqueous metal salt solution with an aqueous solution of a caustic alkali at a pH greater than 8.5 to precipitate out all the metal species. The variation in pH during the precipitation reaction is ±1. The invention also relates to composites formed by this method comprising 20-70 wt % Al2O3, 10-77 wt % ZrO2, 0-34 wt % CeO2 and 0-22 wt % REOs other than CeO2, and to composites per se comprising, on an oxide basis, 42-70 wt % Al2O3, 10-48 wt % ZrO2, 2-34 wt % CeO2 and 0-9 wt % REOs other than CeO2 and having the following properties after heating to 850° C. over four hours and holding at 850° C.

Abstract: An improved method for the formation of composite hydroxides or oxides comprising, on an oxide basis, Al2O3 and ZrO2, and optionally CeO2, La2O3, Nd2O3, Pr6O11, Sm2O3, Y2O3, and other rare earth oxides, comprising the steps of preparing an aqueous metal salt solution and forming a hydroxide precipitate slurry by combining the aqueous metal salt solution with an aqueous solution of a caustic alkali at a pH greater than 8.5 to precipitate out all the metal species. The variation in pH during the precipitation reaction is ±1. The invention also relates to composites formed by this method comprising 20-70 wt % Al2O3, 10-77 wt % ZrO2, 0-34 wt % CeO2 and 0-22 wt % REOs other than CeO2, and to composites per se comprising, on an oxide basis, 42-70 wt % Al2O3, 10-48 wt % ZrO2, 2-34 wt % CeO2 and 0-9 wt % REOs other than CeO2 and having the following properties after heating to 850° C. over four hours and holding at 850° C.

Abstract: Compositions useful for treating the exhaust gases of diesel engines contain zirconium oxide, silicon oxide and at least one oxide of at least one element M selected from among titanium, aluminum, tungsten, molybdenum, cerium, iron, tin, zinc, and manganese, in the following mass proportions of these different elements: silicon oxide: 5%-30%; M-element oxide: 1%-20%; the balance being zirconium oxide; such compositions also have an acidity, as measured by the methylbutynol test, of at least 90% and are prepared by placing a zirconium compound, a silicon compound, at least one M-element compound and a basic compound in a liquid medium, thereby generating a precipitate, maturing the precipitate in a liquid medium and separating and calcining the precipitate.

Abstract: Compositions useful for treating exhaust gases contain zirconium, titanium and tungsten oxides, and optionally the oxide of an element M selected from among silicon, aluminum, iron, molybdenum, manganese, zinc, tin, and rare earths in the following mass proportions of these different elements: titanium oxide: 20%-50%; tungsten oxide: 1%-20%, M-element oxide: 1%-20%; the balance being zirconium oxide; such compositions are prepared by placing in a liquid medium a zirconium compound, a titanium compound, optionally an M-element compound and a basic compound, adding a tungsten compound to the precipitate suspension thus obtained and having a pH value ranging from 1 to 7, maturing the suspension resulting from the preceding step, and optionally separating the precipitate and calcining same.

Abstract: This invention relates to an improved amorphous zirconium hydroxide and a method for its production. The hydroxide has a surface area of at least 300 m2/g, a total pore volume of at least 0.70 cm3/g and an average pore size of between 5 nm and 15 nm, and is prepared by a process which comprises the steps of: a) preparing an aqueous solution comprising sulphate anions and a zirconium salt such that the ZrO2:SO3 ratio is 1:0.40 to 1:0.52, (b) chilling the solution to below 25° C., (c) adding an alkali in order to precipitate the amorphous zirconium hydroxide, (d) filtering and washing the precipitated zirconium hydroxide with water or an alkali to remove residual sulphate and chloride, (e) hydrothermally treating the zirconium hydroxide at a pressure of less than 3 barg, and (f) drying the zirconium hydroxide. The zirconium hydroxide of the present invention, which can be doped, is particularly useful in catalytic applications.

Abstract: A process is disclosed for the preparation of lithium zirconate and doped lithium zirconates for use as regenerable carbon dioxide sorbants by wet mixing zirconium hydroxide with lithium carbonate and then calcining the mixture. Due to the improved physical properties resulting from the disclosed preparation process, the lithium zirconates produced by this process are capable of absorbing carbon dioxide at high rates and in large amounts.

Abstract: The present invention relates to oxygen storage components for catalytic converters for automobile exhaust systems, particularly for those with petrol-driven engines. In accordance with the present invention there is provided a ceria containing mixed oxide suitable as an oxygen storage material having a ceria content in the range 10 to 80% by weight and at least one metal oxide in an amount of less than 0.5% by weight, wherein the metal is selected from the first row transition elements and the group IVB elements of the periodic table. The inventions also provides an oxygen storage material for catalytic converters for automobile exhaust systems comprising an oxide of the present invention.

Abstract: This invention relates to gadolinium-containing magnesium containing alloys, particularly those which possess high strength combined with corrosion resistance, and an optimized balance of strength and ductility. The described alloys consist of 2.0 to 5.0, preferably 2.3 to 4.6, at % in total of gadolinium and at least one of soluble heavy lanthanides and yttrium, wherein the ratio of the aggregate amount of soluble heavy lanthanides and yttrium to the amount of gadolinium is between 1.25:1 and 1.75:1, from 0 up to 0.3 at % of zirconium, preferably at least 0.03 at %, optionally with zinc, wherein when zinc is present the amount of zinc is such that the ratio of the weight of zinc to the weight of zirconium is preferably less than 2:1, all other lanthanides in an aggregate amount of less than at 0.2 at %, the balance being magnesium, with any other element being present in an amount of no more than 0.2 at %.

Abstract: The present invention relates to doped or undoped aluminas having after calcination at 1200° C. for 5-24 hours a pore volume ?0.5 ml/g and a BET surface area greater then 35 m2/g. The invention also relates to a method for preparing these aluminas comprising the steps of: a. preparing an aqueous solution of an aluminum salt with optional co-dopants, b. treating the aqueous solution with hydrogen peroxide, c. precipitating the alumina using a base, and d. filtering, drying and calcining the alumina.

Abstract: This invention relates to an improved amorphous zirconium hydroxide and a method for its production. The hydroxide has a surface area of at least 300 m2/g, a total pore volume of at least 0.70 cm3/g and an average pore size of between 5 nm and 15 nm, and is prepared by a process which comprises the steps of: a) preparing an aqueous solution comprising sulphate anions and a zirconium salt such that the ZrO2:SO3 ratio is 1:0.40 to 1:0.52, (b) chilling the solution to below 25° C., (c) adding an alkali in order to precipitate the amorphous zirconium hydroxide, (d) filtering and washing the precipitated zirconium hydroxide with water or an alkali to remove residual sulphate and chloride, (e) hydrothermally treating the zirconium hydroxide at a pressure of less than 3 barg, and (f) drying the zirconium hydroxide. The zirconium hydroxide of the present invention, which can be doped, is particularly useful in catalytic applications.

Abstract: A process is disclosed for the preparation of lithium zirconate and doped lithium zirconates for use as regenerable carbon dioxide sorbants by wet mixing zirconium hydroxide with lithium carbonate and then calcining the mixture. Due to the improved physical properties resulting from the disclosed preparation process, the lithium zirconates produced by this process are capable of absorbing carbon dioxide at high rates and in large amounts.

Abstract: The invention relates to composite sacrificial anodes, particularly but not exclusively, based on magnesium, and to methods for their production. The composite sacrificial anode (10) for immersion in a corrosive environment comprises a plurality of castings (12) of a sacrificial material each disposed around a corresponding electrical connector for attachment to a structure to be protected, at least a part of the surface of each segment (12) being protected from corrosion by the environment by being adjacent at least one other segment (12), wherein the castings are connected together electrically only via their electrical connectors.

Abstract: An improved method for the formation of composite hydroxides or oxides comprising, on an oxide basis, Al2O3 and ZrO2, and optionally CeO2, La2O3, Nd2O3, Pr6O11, Sm2O3, Y2O3, and other rare earth oxides, comprising the steps of preparing an aqueous metal salt solution and forming a hydroxide precipitate slurry by combining the aqueous metal salt solution with an aqueous solution of a caustic alkali at a pH greater than 8.5 to precipitate out all the metal species. The variation in pH during the precipitation reaction is ±1. The invention also relates to composites formed by this method comprising 20-70 wt % Al2O3, 10-77 wt % ZrO2, 0-34 wt % CeO2 and 0-22 wt % REOs other than CeO2, and to composites per se comprising, on an oxide basis, 42-70 wt % Al2O3, 10-48 wt % ZrO2, 2-34 wt % CeO2 and 0-9 wt % REOs other than CeO2 and having the following properties after heating to 850° C. over four hours and holding at 850° C.

Abstract: The invention relates to composite sacrificial anodes, particularly but not exclusively, based on magnesium, and to methods for their production. The composite sacrificial anode (10) for immersion in a corrosive environment comprises a plurality of castings (12) of a sacrificial material each disposed around a corresponding electrical connector for attachment to a structure to be protected, at least a part of the surface of each segment (12) being protected from corrosion by the environment by being adjacent at least one other segment (12), wherein the castings are connected together electrically only via their electrical connectors.

Abstract: Magnesium alloys for castings having good tensile properties at both ambient and high temperatures and good resistance to creep contain 1.5-10% of yttrium or an yttrium/heavy rare earths mixture and 1-6% of neodymium or a neodymium/lanthanum/praseodymium mixture. The alloys may be heat treated to improve their properties.

Abstract: A magnesium alloy contains the following additives: A1 1-9%, Zn 0-4%, Sn 0.1-5%, Mn 0-1%. It is useful as an anode in cells operating with a salt water electrolyte, especially in batteries powering equipment for deep-sea use in which a pulsed power source is required.

Abstract: Fluid masses comprising molten metal, such as magnesium alloys, are stirred using a loop-shaped paddle rotating about an axis which itself rotates orbitally about a fixed axis, the loop being shaped so that it passes close to substantially the whole of the bottom of the vessel.

Abstract: Fluid masses comprising molten metal, such as magnesium alloys, are stirred using a loop-shaped paddle rotating about an axis which itself rotates orbitally about a fixed axis, the loop being shaped so that it passes close to substantially the whole of the bottom of the vessel.

Abstract: Magnesium alloys having favorable tensile properties contain silver, copper and neodymium. The alloys are subjected to a solution heat treatment followed by ageing to give optimum properties.