The present invention is directed to a metal-promoted zeolite beta catalyst useful in the selective catalytic reduction of nitrogen oxides with ammonia in which the zeolite beta is pre-treated so as to provide the zeolite with improved hydrothermal stability. The stabilized beta zeolite is provided by incorporating into the zeolite structure non-framework aluminum oxide chains. The aluminum oxide chains can be incorporated into the zeolite structure by a unique steaming regimen or by treatment with rare earth metals, such as cerium. The treatment process is unlike well-known methods of dealuminizing zeolites for the purpose of increasing the silica to alumina ratio. In the present invention, the non-framework aluminum oxide is characterized by FT-IR by a peak at 3781+2 cm-1, which when present, stabilizes the zeolite against further dealumination such as under oxidizing and harsh hydrothermal conditions.

HYDROTHERMALLY STABLE METAL PROMOTED ZEOLITE BETA FOR NOx REDUCTION

An absorbent article, such as a diaper, containing cuffs and a topsheet with one or more skin care compositions disposed thereon. The skin care compositions are transferable to the wearer's skin by normal contact and/or wearer motion and/or body heat. The skin care compositions disclosed in the present invention are selected to maintain and/or improve the skin health of the wearer upon transfer during use, for example, to provide a skin protective barrier or a therapeutic benefit; to minimize the abrasion between the cuffs and skin in the area where the cuffs contact the wearer's skin, resulting in less skin irritation; to improve BM clean up on the skin, or to improve the barrier properties of the cuffs.

Absorbent articles having cuffs and topsheet with skin care composition(s) disposed thereon

The mesopore volume in pores of diameters ranging from 2 to 60 nm of zeolite Y materials is increased by the hydrothermal treatment of such zeolites at temperatures above the atmospheric boiling point of the treating solution. Unique zeolites are produced as result of such process.

Process for preparing zeolite Y with increased mesopore volume

Disclosed is a NOx purifying catalyst which is capable of removing NOx sufficiently efficiently even during operations at low temperatures such as operations in diesel cars. Specifically disclosed is a NOx purifying catalyst for processing NOx in an exhaust gas by performing lean/rich control of air/fuel ratio of the exhaust gas. This NOx purifying catalyst comprises at least a first catalyst layer containing a β zeolite containing iron element and a cerium oxide material and a second catalyst layer containing a noble metal, a cerium oxide material and a heat-resistant inorganic oxide. The second catalyst layer and the first catalyst layer are sequentially arranged on a carrier in such a manner that the first catalyst layer forms the uppermost layer.

NOx PURIFYING CATALYST

The new preparation process for making fine high specific surface ceramic powders suitable as catalysts or precursors for ceramics uses lanthanum (or other rare earth lanthanide) oxide as one of the precursors. The oxide is mixed with water to form a liquid slurry, whereby it is transformed to the hydroxide by reaction with water. The resulting hydroxide slurry, which can be milled to reduce the particle size and to speed up the reaction, is then combined, while stirring vigorously to assure homogenous mixing, with a solution of required amount of remaining metal nitrate precursors, for example strontium and cobalt nitrates. The reaction between lanthanum hydroxide and transition metal nitrates produces a coloured (colour depending on the transition metal) slurry consisting of metal hydroxides suspended in aqueous nitrate solution with pH > 2. This perovskite precursor slurry is spray-frozen and freeze dried. The freeze-dried material is transformed to perovskite by slow controlled calcination at temperatures above 550 ~C. For example calcination 12 h at 585 ~C and subsequently 4 h at 620 ~C produces nearly phase pure perovskite having specific surface area of > 10 m2/g, depending on the composition. The perovskite precursor slurry can alternatively be processed first by spray-drying (instead of spray-freezing/freeze-drying) and subsequent calcination.

Process of making fine ceramic powders from aqueous suspensions

Y-type zeolites with unit cell constants of less than 24.14 A are prepared by improving the method of dealumination and aluminum ion exchange. Zeolites with such low unit cell constants have not been known previously.

Stable zeolite of low unit cell constant and method of making same

The present invention discloses a crystalline hydrated layered sodium silicate/amorphous sodium silicate composite material with predetermined hardness ion sequestration properties achieved by control of the process for forming the material, and a process for making the material. The process for producing the crystalline hydrated layered sodium silicate/amorphous sodium silicate composite comprises producing a crystalline sodium disilicate by heating a sodium silicate for a specified time at a specified temperature. The resulting material may include amorphous material, and the crystalline sodium disilicate can be either alpha-phase or delta-phase disilicate. This crystalline sodium disilicate is then hydrolyzed with up to 50 milliequivalents per gram of either H3O+ ions or OH- ions. The resulting material can sequester Ca2+ ions, Mg2+ ions, or both, depending on the starting materials used, processing conditions, and results desired.

Composite silicate materials

The present invention pertains to a crystalline silicate material containing both sodium and potassium cations within the crystalline matrix. The composition of the material is SiO2 / (xNa2O + yK2O) = Z where x + y = 1, 0.75 < x < 1.0 (and therefore 0.0 < y < 0.25), and 1.3 « Z « 3.22. The material possesses predetermined superior hardness ion sequestration properties determined by the composition and processing of the material. The material can be made by any one of several processes which are also set forth.

Crystalline sodium potassium silicates

The present invention discloses a crystalline hydrated layered sodium and potassium silicate/amorphous sodium and potassium silicate composite material with predetermined hardness ion sequestration properties achieved by control of the process for forming the material. The process for producing the crystalline hydrated layered sodium and potassium silicate/amorphous sodium and potassium silicate composite comprises hydrolyzing DB-1 crystalline sodium and potassium silicate glasses as a precursor material to produce the composite material known as DB-2. Hydrolysis of the DB-1 precursor material is achieved by adding typically up to 100 milliequivalents per gram of H3O+ ions or up to 50 milliequivalents per gram of OH- ions. The resulting DB-2 material can sequester Ca2+ ions, Mg2+ ions, or both, depending on the starting materials used, processing conditions, and results desired.

Denkewicz Raymond P

Papers

Stable zeolite of low unit cell constant and method of making same

Composite silicate materials

Crystalline sodium potassium silicates

Crystalline Hydrated layered sodium and potassium silicates and method of producing same