Abstract:
Catalyst support materials, catalysts, methods of making such and uses thereof are described. Methods of making catalyst support material include combining anatase titanic slurry with i) a low molecular weight form of silica; and ii) a source of Mo to form a TiO2—MoO3-SiO2 mixture. Catalyst support material include from about 86% to about 94% weight anatase titanium dioxide; from about 0.1% to about 10% weight MoO3; and from about 0.1% to about 10% weight SiO2. Low molecular weight forms of silica include forms of silica having a volume weighted median size of less than 4 nm and average molecular weight of less than 44,000, either individually or in a combination of two or more thereof. Catalyst include such catalyst support material with from about 0.1 to about 3% weight of V2O5 and optionally from about 0.01% to about 2.5% weight P.
Abstract:
The invention is directed to compositions and processes for the production of silica-stabilized ultrafine anatase titanias and which may further comprise tungsten and vanadia. The surface stabilization may be by treatment of the TiO2 particles with a low molecular weight and/or small nanoparticle form of silica such as, in preferred embodiments, a tetra(alkyl)ammonium silicate or silicic acid, which serves to efficiently maintain the anatase phase and prevent crystal growth under severe thermal and hydrothermal conditions, even in the presence of vanadia. The vanadia catalysts produced from the novel titanias have equal or improved catalytic activity for selective catalytic reduction of NOx compared to conventional vanadia supported silica-titania based catalysts. The invention is further directed to diesel emission catalytic devices comprising the novel titania-based catalyst compositions.
Abstract:
The invention is directed to compositions and processes for the production of silica-stabilized ultrafine anatase titanias and which may further comprise tungsten and vanadia. The surface stabilization may be by treatment of the TiO2 particles with a low molecular weight and/or small nanoparticle form of silica such as, in preferred embodiments, a tetra(alkyl)ammonium silicate or silicic acid, which serves to efficiently maintain the anatase phase and prevent crystal growth under severe thermal and hydrothermal conditions, even in the presence of vanadia. The vanadia catalysts produced from the novel titanias have equal or improved catalytic activity for selective catalytic reduction of NOx compared to conventional vanadia supported silica-titania based catalysts. The invention is further directed to diesel emission catalytic devices comprising the novel titania-based catalyst compositions.
Abstract:
The disclosure provides a metal oxide-doped titanium dioxide (TiO2) composition, with a solid phase including TiO2 and one or more metal oxides and a liquid phase. Methods of preparing such doped compositions are also provided. The doped compositions disclosed herein can exhibit adsorption and photocatalytic properties, particularly in the context of treating gas streams containing H2S gas (e.g., to reduce atmospheric pollution).
Abstract:
Catalyst support materials, catalysts, methods of making such and uses thereof are described. Methods of making catalyst support material include combining anatase titania slurry with i) a low molecular weight form of silica; and ii) a source of Mo to form a TiO2—MoO3—SiO2 mixture. Catalyst support material include from about 86% to about 94% weight anatase titanium dioxide; from about 0.1% to about 10% weight MoO3; and from about 0.1% to about 10% weight SiO2. Low molecular weight forms of silica include forms of silica having a volume weighted median size of less than 4 nm and average molecular weight of less than 44,000, either individually or in a combination of two or more thereof. Catalyst include such catalyst support material with from about 0.1 to about 3% weight of V2O5 and optionally from about 0.01% to about 2.5% weight P.
Abstract:
Catalyst support materials, catalysts, methods of making such and uses thereof are described. Methods of making catalyst support material include combining anatase titania slurry with i) a low molecular weight form of silica; and ii) a source of Mo to form a TiO2—MoO3—SiO2 mixture. Catalyst support material include from about 86% to about 94% weight anatase titanium dioxide; from about 0.1% to about 10% weight MoO3; and from about 0.1% to about 10% weight SiO2. Low molecular weight forms of silica include forms of silica having a volume weighted median size of less than 4 nm and average molecular weight of less than 44,000, either individually or in a combination of two or more thereof. Catalyst include such catalyst support material with from about 0.1 to about 3% weight of V2O5 and optionally from about 0.01% to about 2.5% weight P.
Abstract:
The invention is directed to compositions and processes for the production of silica-stabilized ultrafine anatase titanias and which may further comprise tungsten and vanadia. The surface stabilization may be by treatment of the TiO2 particles with a low molecular weight and/or small nanoparticle form of silica such as, in preferred embodiments, a tetra(alkyl)ammonium silicate or silicic acid, which serves to efficiently maintain the anatase phase and prevent crystal growth under severe thermal and hydrothermal conditions, even in the presence of vanadia. The vanadia catalysts produced from the novel titanias have equal or improved catalytic activity for selective catalytic reduction of NOx compared to conventional vanadia supported silica-titania based catalysts. The invention is further directed to diesel emission catalytic devices comprising the novel titania-based catalyst compositions.
Abstract:
Catalyst support materials, catalysts, methods of making such and uses thereof are described. Methods of making catalyst support material include combining anatase titania slurry with i) a low molecular weight form of silica; and ii) a source of Mo to form a TiO2—MoO3—SiO2 mixture. Catalyst support material include from about 86% to about 94% weight anatase titanium dioxide; from about 0.1% to about 10% weight MoO3; and from about 0.1% to about 10% weight SiO2. Low molecular weight forms of silica include forms of silica having a volume weighted median size of less than 4 nm and average molecular weight of less than 44,000, either individually or in a combination of two or more thereof. Catalyst include such catalyst support material with from about 0.1 to about 3% weight of V2O5 and optionally from about 0.01% to about 2.5% weight P.
Abstract:
Catalyst support materials, catalysts, methods of making such and uses thereof are described. Methods of making catalyst support material include combining anatase titania slurry with i) a low molecular weight form of silica; and ii) a source of Mo to form a TiO2—MoO3—SiO2 mixture. Catalyst support material include from about 86% to about 94% weight anatase titanium dioxide; from about 0.1% to about 10% weight MoO3; and from about 0.1% to about 10% weight SiO2. Low molecular weight forms of silica include forms of silica having a volume weighted median size of less than 4 nm and average molecular weight of less than 44,000, either individually or in a combination of two or more thereof. Catalyst include such catalyst support material with from about 0.1 to about 3% weight of V2O5 and optionally from about 0.01% to about 2.5% weight P.