Magnesium Elektron, Inc.

Rhodia Operations

University of Kentucky Research Foundation

Deborah Jayne Harris

Olivier Larcher

David Alastair Scapens

Emmanuel Rohart

Julien Hernandez

Guillaume Criniere

Stephan Verdier

Rui Jorge Coelho Marques

Clare Jones

Mark Crocker

Mila Bortun

Hazel Stephenson

John G Darab

Heather Bradshaw

Yaying Ji

Laure Bisson

Clive Butler

Iryna Chepurna

Mairead Feeley

David Scapens

This invention relates to an aqueous dispersion of particles, the dispersion having a particle content of 10-70 wt %, and the particles comprising, on an oxide basis: (a) 10-98 wt % in total of ZrO+HfO, and (b) 2-90 wt % in total of AlO, CeO, LaO, NdO, PrO, YO, or a transition metal oxide, wherein the dispersion has a Z-average particle size of 100-350 nm and the particles have a crystallite size of 1-9 nm. The invention also relates to a substrate coated with the aqueous dispersion of particles.

Zirconia-based aqueous np-dispersion for use in coating filter substrates

This invention relates to azirconium hydroxideor zirconium oxide comprising, on an oxide basis, up to 30 wt % of a dopant comprising one or more of silicon, sulphate, phosphate, tungsten, niobium, aluminium, molybdenum, titanium or tin, and having acid sites, wherein the majority of the acid sites are Lewis acid sites. In addition, the invention relates to a catalyst, catalyst support or precursor, binder, functional binder, coating or sorbent comprising the zirconium hydroxide or zirconium oxide. The invention also relates to a process for preparing zirconium hydroxide, the process comprising the steps of:(a) dissolving a zirconium salt in an aqueous acid, (b) addingone or more complexing agents to the resulting solution or sol, the one or more complexing agents being an organic compound comprising at least one of the following functional groups: an amine, an organosulphate, a sulphonate, a hydroxyl, an ether or a carboxylic acid group, (c) heating the solution or sol formed in step (b), (d) adding a sulphating agent, and (e) adding a base to form a zirconium hydroxide, and (f) optionally adding a dopant.

Acidic zirconium hydroxide

A cerium-zirconium based mixed oxide composition have: (a) a Ce:Zr molar ratio of 1 or less, and (b) a cerium oxide content of 10-50% by weight. The composition has (i) a surface area of at least 18 m/g, and a total pore volume as measured by Nphysisorption of at least 0.11 cm/g, after ageing at 1100&#xb0; C. in an air atmosphere for 6 hours, (ii) a surface area of at least 42 m/g, and a total pore volume as measured by Nphysisorption of at least 0.31 cm/g, after ageing at 1000&#xb0; C. in an air atmosphere for 4 hours, and (iii) Dynamic Oxygen Storage Capacity (D-OSC) value as measured by H-TIR of greater than 500 &#x3bc;mol/g at 600&#xb0; C. after aging at 800&#xb0; C. in an air atmosphere for 2 hours. A process contacts the exhaust gas with the composition Another process is for preparing the composition.

Zirconia-based compositions for use as three way catalysts

A passive NOadsorbent includes: palladium, platinum or a mixture thereof and a mixed or composite oxide including the following elements in percentage by weight, expressed in terms of oxide: 10-90% by weight zirconium and 0.1-50% by weight of least one of the following: a transition metal or a lanthanide series element other than Ce. Although the passive NOadsorbent can include Ce in an amount ranging from 0.1 to 20% by weight expressed in terms of oxide, advantages are obtained particularly in the case of low-Ce or a substantially Ce-free passive NOx adsorbent.

Zirconia-based compositions for use in passive NOx adsorber devices

The invention relates to a method for treating a gas containing nitrogen oxides (NOx), in which an NOx-reduction reaction is carried out using a nitrogen-containing reducing agent, which invention is characterized in that the catalyst used for the reduction reaction is a catalytic system containing a composition comprising zirconium, cerium and niobium in the following percentages by weight, expressed in terms of the weight of oxide: 10-50% of cerium, 5-20% of niobium and the remainder consisting of zirconium.

[object Object]

A method is described for treating a gas including nitrogen oxides (NO). The method can include conducting a reduction reaction of the nitrogen oxides with a nitrogen reducing agent. Further described, is a catalyst used for the reduction reaction which is a catalytic system including a composition based on cerium oxide and including niobium oxide in a proportion by a mass of from 2% to 20%.

Method for treating a gas containing nitrogen oxides (NOx), in which a composition comprising cerium oxide and niobium oxide is used as a catalyst

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Manchester, United Kingdom

Deborah Jayne Harris