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.

Redox catalysts having surface medication, methods of making redox catalysts with surface modification, and uses of the surface modified redox catalysts are provided. In some aspects, the redox catalysts include a core oxygen carrier region such as CaMnO.sub.3, BaMnO.sub.3−δ, SrMnO.sub.3−δ, Mn.sub.2SiO.sub.4, Mn.sub.2MgO.sub.4−δ, La.sub.0.8Sr.sub.0.2O.sub.3−δ, La.sub.0.8Sr.sub.0.2FeO.sub.3−δ, Ca.sub.9Ti.sub.0.1Mn.sub.0.9O.sub.3−δ, Pr.sub.6O.sub.11−δ, manganese ore, or a combination thereof; and an outer shell having an average thickness of about 1-100 monolayers surrounding the outer surface of the core region. The outer shell can include, for example a salt selected such as Li.sub.2WO.sub.4, Na.sub.2WO.sub.4, K.sub.2WO.sub.4, SrWO.sub.4, Li.sub.2MoO.sub.4, Na.sub.2MoO.sub.4, K.sub.2MoO.sub.4, CsMoO.sub.4, Li.sub.2CO.sub.3, Na.sub.2CO.sub.3, K.sub.2CO.sub.3, or a combination thereof.

Redox catalysts having surface medication, methods of making redox catalysts with surface modification, and uses of the surface modified redox catalysts are provided. In some aspects, the redox catalysts include a core oxygen carrier region such as CaMnO.sub.3, BaMnO.sub.3−δ, SrMnO.sub.3−δ, Mn.sub.2SiO.sub.4, Mn.sub.2MgO.sub.4−δ, La.sub.0.8Sr.sub.0.2O.sub.3−δ, La.sub.0.8Sr.sub.0.2FeO.sub.3−δ, Ca.sub.9Ti.sub.0.1Mn.sub.0.9O.sub.3−δ, Pr.sub.6O.sub.11−δ, manganese ore, or a combination thereof; and an outer shell having an average thickness of about 1-100 monolayers surrounding the outer surface of the core region. The outer shell can include, for example a salt selected such as Li.sub.2WO.sub.4, Na.sub.2WO.sub.4, K.sub.2WO.sub.4, SrWO.sub.4, Li.sub.2MoO.sub.4, Na.sub.2MoO.sub.4, K.sub.2MoO.sub.4, CsMoO.sub.4, Li.sub.2CO.sub.3, Na.sub.2CO.sub.3, K.sub.2CO.sub.3, or a combination thereof.

Methods for preparing molybdenum-based catalyst for epoxidation reactions using MPG sourced from a propylene oxide/styrene monomer (POSM) production process are described. Streams exiting from the POSM reactor are combined and separated to isolate an aqueous-based, MPG-containing purge stream from other recoverable byproducts of the POSM process. This MPG-containing purge stream is then used as is in the catalyst preparation of molybdenum-based catalyst for epoxidation. Alternatively, the MPG-containing purge stream can undergo additional purification treatments before being utilized in the catalyst preparation.

The present invention relates to a method for preparing titanium dioxide nanofibers surface-doped with noble metal ions through electrohydrodynamic transport. Titanium dioxide nanofibers according to the present invention can be used for reducing viruses, bacteria, and volatile organic compounds in the air.

The present invention relates to a method for preparing titanium dioxide nanofibers surface-doped with noble metal ions through electrohydrodynamic transport. Titanium dioxide nanofibers according to the present invention can be used for reducing viruses, bacteria, and volatile organic compounds in the air.

A method of producing bifunctional catalysts by extrusion may include mixing an acid catalyst, a metal catalyst, optionally a binder, and a fluid to produce a dough; extruding the dough to form an extrudate; producing a powder from the extrudate; and calcining the powder to produce an acid/metal bifunctional catalyst. Such acid/metal bifunctional catalysts may be useful in, among other things, converting syngas to dimethyl ether in a single reactor.

A method of producing bifunctional catalysts by extrusion may include mixing an acid catalyst, a metal catalyst, optionally a binder, and a fluid to produce a dough; extruding the dough to form an extrudate; producing a powder from the extrudate; and calcining the powder to produce an acid/metal bifunctional catalyst. Such acid/metal bifunctional catalysts may be useful in, among other things, converting syngas to dimethyl ether in a single reactor.

A method of producing a catalytic carbon fiber may include: oxidizing a virgin carbon fiber to produce an oxidized carbon fiber; reacting the oxidized carbon fiber with a polyamine compound to produce an amine modified carbon fiber; and reacting the amine modified carbon fiber with an organometallic macrocycle to produce the catalytic carbon fiber.