摘要:
An apparatus and method for treating diesel exhaust gases are described. The system consists of two functionalities, the first being a selective catalytic reduction (SCR) catalyst system and the second being a capture material for capturing catalyst components such as vanadia that have appreciable volatility under extreme exposure conditions. The SCR catalyst component is typically based on a majority phase of titania, with added minority-phase catalyst components comprising of one or more of the oxides of vanadium, silicon, tungsten, molybdenum, iron, cerium, phosphorous, copper and/or manganese vanadia. The capture material typically comprises a majority phase of high surface area oxides such as silica-stabilized titania, alumina, or stabilized alumina, for example.
摘要:
An apparatus and method for treating diesel exhaust gases are described. The system consists of two functionalities, the first being a selective catalytic reduction (SCR) catalyst system and the second being a capture material for capturing catalyst components that have appreciable volatility under extreme exposure conditions. The SCR catalyst component is typically based on a majority phase of titania, with added minority-phase catalyst components comprising of one or more of the oxides of vanadium, silicon, tungsten, molybdenum, iron, cerium, phosphorous, copper and/or manganese vanadia. The capture material typically comprises a majority phase of high surface area oxides such as silica-stabilized titania, alumina, or stabilized alumina, for example, wherein the capture material maintains a low total fractional monolayer coverage of minority phase oxides for the duration of the extreme exposure. The method involves treatment of hot exhaust streams by both the catalyst material and capture material, wherein the capture material can be in a mixture with the catalyst material, or can be located downstream thereof, or both, but still be maintained at the extreme temperatures. Volatile catalyst components such as vanadia are thus removed from the vapor phase of the exhaust gas.
摘要:
The present invention relates to a process for the production of an elemental material, comprising the step of reacting a halide of the elemental material with a reducing agent in solid form in a fluidized bed reactor at a reaction temperature which is below the melting temperature of the reducing agent. In a preferred embodiment of the present invention, the elemental material is titanium and the titanium is produced in powder form. The invention also relates to the production of alloys or intermetallics of the elemental materials.
摘要:
A system for manufacturing a pigment comprising an oxidation reactor capable of providing a pigment, a scouring media source, and a heat exchanger having a tubular conduit through which the mixture of the pigment and the scouring media flows. The tubular conduit having an inlet, an outlet, and a longitudinal center line. The tubular conduit configured such that at least a portion of the longitudinal center line of the tubular conduit extends in a helical pattern.
摘要:
The present invention is directed to high activity titanium oxide DeNOx catalysts. In preferred embodinents, by depositing vanadium oxide on a titania supported metal oxide such as tungsten oxide, an improved catalyst may be generated. This catalyst may be used in the treatment of exhaust from sources such as automobiles and industrial plants.
摘要:
De-polluting, self-cleaning coating compositions are disclosed which comprise an extender that comprises a mixture of calcium carbonate and one or more alternate extenders. The coatings of the invention exhibit improved durability and opacity without affecting the photocatalytic removal of NOx compounds.