Abstract: A durable catalyst support/catalyst is capable of extended water gas shift operation under-conditions of high temperature, pressure, and sulfur levels. The support is a homogeneous, nanocrystalline, mixed metal oxide of at least three metals, the first being cerium, the second being Zr, and/or Hf, and the third importantly being Ti, the three metals comprising at least 80% of the metal constituents of the mixed metal oxide and the Ti being present in a range of 5% to 45% by metals-only atomic percent of the mixed metal oxide. The mixed metal oxide has an average crystallite size less than 6 nm and forms a skeletal structure with pores whose diameters are in the range of 4-9 nm and normally greater than the average crystallite size. The surface area of the skeletal structure per volume of the material of the structure is greater than about 240 m2/cm3. The method of making and use are also described.

Abstract: A homogeneous ceria-based mixed-metal oxide, useful as a catalyst support, a co-catalyst and/or a getter has a relatively large surface area per weight, typically exceeding 150 m2/g, a structure of nanocrystallites having diameters of less than 4 nm, and including pores larger than the nanocrystallites and having diameters in the range of 4 to about 9 nm. The ratio of pore volumes, VP, to skeletal structure volumes, VS, is typically less than about 2.5, and the surface area per unit volume of the oxide material is greater than 320 m2/cm3, for low internal mass transfer resistance and large effective surface area for reaction activity. The mixed metal oxide is ceria-based, includes Zr and or Hf, and is made by a novel co-precipitation process. A highly dispersed catalyst metal, typically a noble metal such as Pt, may be loaded on to the mixed metal oxide support from a catalyst metal-containing solution following a selected acid surface treatment of the oxide support.

Abstract: A homogeneous ceria-based mixed-metal oxide, useful as a catalyst support, a co-catalyst and/or a getter has a relatively large surface area per weight, typically exceeding 150 m2/g, a structure of nanocrystallites having diameters of less than 4 nm, and including pores larger than the nanocrystallites and having diameters in the range of 4 to about 9 nm. The ratio of pore volumes, VP, to skeletal structure volumes, VS, is typically less than about 2.5, and the surface area per unit volume of the oxide material is greater than 320 m2/cm3, for low internal mass transfer resistance and large effective surface area for reaction activity. The mixed metal oxide is ceria-based, includes Zr and or Hf, and is made by a novel co-precipitation process. A highly dispersed catalyst metal, typically a noble metal such as Pt, may be loaded on to the mixed metal oxide support from a catalyst metal-containing solution following a selected acid surface treatment of the oxide support.

Abstract: A vehicle has a body and a source of a propellant. An engine is carried by the body. The engine reacts the propellant to produce thrust. The engine has a heat exchanger transferring heat from the reaction to at least a component of the propellant and generating electricity thermoelectrically.

Abstract: A doped, nanocrystalline, ceria-containing, mixed metal oxide supports a noble metal to provide a thermally-durable catalyst for processing carbonaceous fuels, particularly for the water gas shift reactions. The mixed metal oxide includes Zr and/or Hf and is normally susceptible to oxide ion vacancy ordering at elevated temperature reducing conditions. A dopant is selected to inhibit such oxide ion vacancy ordering. The dopant is preferably selected from the group consisting of W, Mo, Ta, and Nb, most preferably W, for providing a thermally-durable catalyst at operating temperatures exceeding 400° C. The noble metal is preferably Pt and/or Re. The doped ceria-containing mixed metal oxide is prepared from 2 or 3 aqueous solutions variously containing ceria, Zr and/or Hf, the dopant, and urea. The solutions are heated to below boiling, combined in a particular sequence and manner, and brought to boiling to crystallize and precipitate the doped ceria-containing mixed metal oxide.