Supported chromium catalysts with an average valence less than +6 and having a hydrocarbon-containing or halogenated hydrocarbon-containing ligand attached to at least one bonding site on the chromium are disclosed, as well as ethylene-based polymers with terminal alkane, aromatic, or halogenated hydrocarbon chain ends. Another ethylene polymer characterized by at least 2 wt. % of the polymer having a molecular weight greater than 1,000,000 g/mol and at least 1.5 wt. % of the polymer having a molecular weight less than 1000 g/mol is provided, as well as an ethylene homopolymer with at least 3.5 methyl short chain branches and less than 0.6 butyl short chain branches per 1000 total carbon atoms.

The present invention relates to the field of heterogeneous catalysis. In more detail, it refers to a process for reducing the sulphur content of a stabilized titania, the so-obtained material and the use thereof for manufacturing of support materials for heterogeneous catalysts.

Methods for making a supported chromium catalyst are disclosed, and can comprise contacting a silica-coated alumina containing at least 30 wt. % silica with a chromium-containing compound in a liquid, drying, and calcining in an oxidizing atmosphere at a peak temperature of at least 650° C. to form the supported chromium catalyst. The supported chromium catalyst can contain from 0.01 to 20 wt. % chromium, and typically can have a pore volume from 0.5 to 2 mL/g and a BET surface area from 275 to 550 m.sup.2/g. The supported chromium catalyst subsequently can be used to polymerize olefins to produce, for example, ethylene-based homopolymers and copolymers having high molecular weights and broad molecular weight distributions.

Methods for making a supported chromium catalyst are disclosed, and can comprise contacting a silica-coated alumina containing at least 30 wt. % silica with a chromium-containing compound in a liquid, drying, and calcining in an oxidizing atmosphere at a peak temperature of at least 650° C. to form the supported chromium catalyst. The supported chromium catalyst can contain from 0.01 to 20 wt. % chromium, and typically can have a pore volume from 0.5 to 2 mL/g and a BET surface area from 275 to 550 m.sup.2/g. The supported chromium catalyst subsequently can be used to polymerize olefins to produce, for example, ethylene-based homopolymers and copolymers having high molecular weights and broad molecular weight distributions.

An object of the present invention is to extend the catalyst lifetime in a method for producing fluoromethane by pyrolyzing fluorine-containing methyl ether in the presence of a catalyst. The present invention provides a method for producing fluoromethane by pyrolyzing a fluorine-containing methyl ether represented by Formula (1) in a gas phase in the presence of a catalyst,

the pyrolysis being conducted at a moisture concentration of 100 ppm or less,

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wherein R.sup.1 and R.sup.2 are identical or different, and each represents a substituted or unsubstituted straight or branched monovalent aliphatic hydrocarbon group, substituted or unsubstituted monovalent aromatic hydrocarbon group, substituted or unsubstituted monovalent cyclic aliphatic hydrocarbon group, hydrogen atom, or halogen atom.

The present invention relates to a process for preparing 1,4-butanediol (BDO) by hydrogenating 2-butyne-1,4-diol (BYD) or 4-hydroxybutanal (4-HBA) in the presence of a catalyst of the Raney type having a porous foam structure, wherein the macroscopic pores have sizes in the range of 100 to 5000 μm, and a bulk density of up to 0.8 kg/L.

An electrode assembly includes a first electrode and a dielectric layer on the first electrode. The dielectric layer includes a bismuth compound of the formula Bi.sub.2(CrO.sub.4).sub.2Cr.sub.2O.sub.7, Pb.sub.4(BiO.sub.4)(PO.sub.4), Ag.sub.3BiO.sub.3, Bi.sub.2CdO.sub.2(GeO.sub.4), Bi.sub.2Te.sub.4O.sub.11, Cs.sub.6Bi.sub.4O.sub.9, Na.sub.3Bi(PO.sub.4).sub.2, Bi.sub.2(SeO.sub.3).sub.3, or a combination thereof. The electrode assembly can be particularly useful in various electronic devices.

The present invention provides a process for preparation of 2,3,3,3-tetrafluoropropene and intermediates thereof. Owing to its low global warming potential and zero ozone depleting potential, it is been proposed as a replacement for existing chlorofluorocarbons and hydrofluorocarbons as refrigerant.

The present invention provides a process for preparation of 2,3,3,3-tetrafluoropropene and intermediates thereof. Owing to its low global warming potential and zero ozone depleting potential, it is been proposed as a replacement for existing chlorofluorocarbons and hydrofluorocarbons as refrigerant.

A method of preparing a catalyst comprising a) contacting a non-aqueous solvent, a carboxylic acid, and a chromium-containing compound to form an acidic mixture; b) contacting a titanium-containing compound with the acidic mixture to form a titanium treatment solution; c) contacting a pre-formed silica-support comprising from about 0.1 wt. % to about 20 wt. % water with the titanium treatment solution to form a pre-catalyst; and d) thermally treating the pre-catalyst to form the catalyst. A method of preparing a catalyst comprising a) contacting a non-aqueous solvent and a carboxylic acid to form an acidic mixture; b) contacting a titanium-containing compound with the acidic mixture to form a titanium treatment solution; c) contacting a pre-formed chrominated silica-support comprising from about 0.1 wt. % to about 20 wt. % water with the titanium treatment solution to form a pre-catalyst; and d) thermally treating the pre-catalyst to form the catalyst.