A filter for air purification includes an air-permeable body frame and a photocatalyst member provided in the body frame. The photocatalyst member includes at least one mesh slit and a plurality of bead layers disposed on both sides of the mesh slit to be spaced apart from each other wherein the bead layers include a plurality of photocatalyst-containing beads aligned in a single layer to be spaced apart from each other at regular intervals.

Provided is a beta zeolite satisfying P>76.79Q?29.514 in a range in which Q is less than 0.4011 nm, wherein, P represents an AB value that is an intensity ratio of A to B, A represents a diffraction intensity of a main peak of the beta zeolite observed by X-ray diffraction measurement, B represents a diffraction intensity of the (116) plane of ?-alumina obtained by X-ray diffraction measurement under the same conditions as those for the X-ray diffraction measurement on the beta zeolite, the ?-alumina being the standard substance 674a distributed by the American National Institute of Standards and Technology, and Q represents a lattice interplanar spacing of the main peak of the beta zeolite observed by X-ray diffraction measurement. It is preferable that the formula (1) above is satisfied in a range in which Q is from 0.3940 to 0.4000 nm.

A method for preparing a silica-modified catalyst support is described including: (i) applying an alkyl silicate to the surface of a porous support material in an amount to produce a silica content of the silica-modified catalyst support, expressed as Si, in the range 0.25 to 15% by weight, (ii) optionally drying the resulting silicate-modified support, (iii) treating the support with water, (iv) drying the resulting water-treated support, and (v) calcining the dried material to form the silica-modified catalyst support.

The present invention provides a method for preparing acetic acid by carbonylation of methanol, which comprises: passing a raw material containing methanol, carbon monoxide and water through a reaction region loaded with a catalyst containing an acidic molecular sieve with an adsorbed organic amine, and carrying out a reaction under the following conditions to prepare acetic acid. The method in the present invention offers high acetic acid selectivity and good catalyst stability. The catalyst in the present invention does not contain noble metals such as rhodium or iridium, and does not need additional agent containing iodine, and thus does not generate a strong corrosive hydroiodic acid and the like.

Embodiments of processes for producing propylene utilize a dual catalyst system comprising a mesoporous silica catalyst impregnated with metal oxide and a mordenite framework inverted (MFI) structured silica catalyst downstream of the mesoporous silica catalyst, where the mesoporous silica catalyst includes a pore size distribution of at least 2.5 nm to 40 nm and a total pore volume of at least 0.600 cm.sup.3/g, and the MFI structured silica catalyst has a total acidity of 0.001 mmol/g to 0.1 mmol/g. The propylene is produced from the butene stream via metathesis by contacting the mesoporous silica catalyst and subsequent cracking by contacting the MFI structured silica catalyst.

The invention relates to a molecular sieve modification method and a catalytic cracking catalyst containing a molecular sieve. The method comprises: mixing a solution containing an ion of a Group MB metal in the periodic table, an organic complexing agent, and/or a dispersant and a precipitation agent, and stirring the same to form a suspension containing a precipitant of a Group IIIB element; and mixing the resulting precipitant and a molecular sieve slurry, stirring the same to obtain a mixed slurry containing the precipitant of the Group MB element and a molecular sieve, and performing spray drying and optional calcination, to obtain a modified molecular sieve. The catalyst comprises, as calculated based on the catalyst mass being 100%, 10-55% of a modified molecular sieve (on a dry basis), 10-80% of clay (on a dry basis), 0-40% of an inorganic oxide (on an oxide basis), and 5-40% of a binding agent (on an oxide basis). The catalyst has good activity stability and heavy metal contamination resistance.

An extruded, solid honeycomb body comprises a copper-promoted, small pore, crystalline molecular sieve catalyst for converting oxides of nitrogen in the presence of a reducing agent, wherein the crystalline molecular sieve contains a maximum ring size of eight tetrahedral atoms, which extruded, solid honeycomb body comprising: 20-50% by weight matrix component comprising diatomaceous earth, wherein 2-20 weight % of the extruded, solid honeycomb body is diatomaceous earth; 80-50% by weight of the small pore, crystalline molecular sieve ion-exchanged with copper; and 0-10% by weight of inorganic fibres.

Provided is a catalyst for the selective reduction of NOx comprising a two molecular sieve materials having a CHA structure, wherein the first molecular sieve has a mean crystal size of about 0.01 to 1 m and the second molecular sieve has a mean crystal size of about 1-5 m, and wherein the first molecular sieve contains a first extra-framework metal, the second molecular sieve contains a second extra-framework metal, and wherein said first and second extra-framework metals are independently selected from the group consisting of cesium, copper, nickel, zinc, iron, tin, tungsten, molybdenum, cobalt, bismuth, titanium, zirconium, antimony, manganese, chromium, vanadium, niobium, and combinations thereof.

Catalyst compositions suitable for use in the exhaust gas recycle stream of an internal combustion engine are provided. Such catalyst compositions typically provide significant amounts of methane in addition to syngas. A reformer incorporating such a catalyst for use in an exhaust gas recycle portion of an internal combustion engine powertrain is described. A powertrain incorporating such a reformer, a method of increasing the octane rating of an exhaust gas recycle stream, and a method of operating an internal combustion engine using methane-assisted combustion are also described.

The present invention relates to zeolite materials in the form of agglomerates comprising at least one mesoporous zeolite and having both the characteristics of mesoporous zeolites, the properties associated with microporosity and the mechanical properties of zeolite agglomerates without mesoporous zeolite. The invention also relates to the process for preparing the said zeolite materials in the form of agglomerates.