摘要:
A catalytic vessel for adsorbing catalytic metals, such as from automotive exhaust gases, and carrying out three-way catalysis includes an inlet at an upstream end, a plurality of catalytic chambers located downstream of the inlet, and an outlet. At least one of the catalytic chambers contains a plurality of sheet members preferably made of steel and adapted for deposition of a metal selected from the group of noble and non-noble metals, and more particularly from the group including platinum, rhodium, rhenium, palladium, and gold. The vessel may be used in a catalytic system which contains a liquid source of metal catalysts, such as a solution or a gasoline additive, from which the metal catalysts are added to a combustion system, and the catalytic vessel, which collects the metal catalysts and is a site for three-way catalytic conversion of starting materials such as automotive emissions to final products.
摘要:
A thin-walled monolithic iron oxide structure, and process for making such a structure, is disclosed. The structure comprises a monolithic iron oxide structure obtained from oxidizing a thin-walled iron-containing, preferably plain steel, structure at a temperature below the melting point of iron. The preferred wall thickness of the steel is less than about 0.3 mm. The preferred iron oxides of the invention are hematite, magnetite, and combinations thereof. The thin-walled structures of the invention have substantially the same physical shape as the iron starting structure. Thin-walled iron-oxide structures of the invention can be used in a wide variety of applications, including gas and liquid flow dividers, corrosion resistant components of automotive exhaust systems, catalytic supports, filters, thermal insulating materials, and sound insulating materials. Iron oxides of the invention consisting substantially of magnetite can be electrically heated and, therefore, can be applicable in applications such as electrically heated thermal insulation, electric heating of liquids and gases passing through channels, and incandescent devices. Additionally, combination structures using both magnetite and hematite can be fabricated.
摘要:
Monolithic metal oxide structures, and processes for making such structures, are disclosed. The structures are obtained by heating a metal-containing structure having a plurality of surfaces in close proximity to one another in an oxidative atmosphere at a temperature below the melting point of the metal while maintaining the close proximity of the metal surfaces. Exemplary structures of the invention include open-celled and closed-cell monolithic metal oxide structures comprising a plurality of adjacent bonded corrugated and/or flat layers, and metal oxide filters obtained from a plurality of metal filaments oxidized in close proximity to one another.
摘要:
Catalytic metal additives that directly dissolve in gasoline in concentrations providing efficient and economical three-way catalysis of exhaust gases from internal combustion engines. The additives are compounds of noble (e.g., Pt, Pd, Au and Rh) or non-noble (e.g., Re) metals. The preferred compounds have polar metal ligand bonds, preferably with inorganic ligands such as halogens, oxygen, etc., and/or salts with highly ionic (polarizable) cations such as of alkali metals. The preferred additive is a combination of X.sub.2 PtCl.sub.6, RhCl.sub.3 and XReO.sub.4, where X=K, Rh or Cs. A combination of these finely ground materials is fabricated into a briquette or filter which is deposited in the gas tank or placed in a gas line. The catalytic metals are carried by the exhaust gases through the exhaust system where they are deposited on surfaces of the system to convert toxic emissions. In this way, the invention allows for the delivery of efficient gasoline additives without the use of solvents or extraneous agents.
摘要:
Monolithic metal oxide structures, and processes for making such structures, are disclosed. The structures are obtained by heating a metal-containing structure having a plurality of surfaces in close proximity to one another in an oxidative atmosphere at a temperature below the melting point of the metal while maintaining the close proximity of the metal surfaces. Exemplary structures of the invention include open-celled and closed-cell monolithic metal oxide structures comprising a plurality of adjacent bonded corrugated and/or flat layers, and metal oxide filters obtained from a plurality of metal filaments oxidized in close proximity to one another.
摘要:
A catalytic vessel for adsorbing catalytic metals, such as from automotive exhaust gases, and carrying out three-way catalysis includes an inlet at an upstream end, a plurality of catalytic chambers located downstream of the inlet, and an outlet. At least one of the catalytic chambers contains a plurality of sheet members preferably made of steel and adapted for deposition of a metal selected from the group of noble and non-noble metals, and more particularly from the group consisting of platinum, rhodium, rhenium, palladium, and gold. The vessel may be used in a catalytic system which contains a liquid source of metal catalysts, such as a solution or a gasoline additive, means for adding metal catalysts to a combustion system, and the catalytic vessel, which collects the metal catalysts and is a site for three-way catalytic conversion of starting materials such as automotive emissions to final products.
摘要:
Methods of making metal oxide articles, preferably iron oxide articles, and articles thereby produced. The method comprises the steps of slightly pressing powder to a compact, the powder consisting essentially of a first oxide of the metal; and subjecting the compact to a heat treatment that causes the powder to sinter into a unitary body and results in the transformation of at least a portion of the first oxide to a second oxide by oxidation or deoxidation during the heat treatment. In disclosed embodiments, the heat treatment is conducted either in air at atmospheric pressure or at a subatmospheric pressure. The method optionally includes more heating/cooling steps resulting in additional oxidation/deoxidation cycles. Sintered iron oxide articles of the invention have high mechanical strengths and interconnected pore structures, providing for efficient filtering of liquids and gases.
摘要:
Monolithic metal oxide structures, and processes for making such structures, are disclosed. The structures are obtained by heating a metal-containing structure having a plurality of surfaces in close proximity to one another in an oxidative atmosphere at a temperature below the melting point of the metal while maintaining the close proximity of the metal surfaces. Exemplary structures of the invention include open-celled and closed-cell monolithic metal oxide structures comprising a plurality of adjacent bonded corrugated and/or flat layers, and metal oxide filters obtained from a plurality of metal filaments oxidized in close proximity to one another.
摘要:
Monolithic metal oxide structures, and processes for making such structures, are disclosed. The structures are obtained by heating a metal-containing structure having a plurality of surfaces in close proximity to one another in an oxidative atmosphere at a temperature below the melting point of the metal while maintaining the close proximity of the metal surfaces. Exemplary structures of the invention include open-celled and closed-cell monolithic metal oxide structures comprising a plurality of adjacent bonded corrugated and/or flat layers, and metal oxide filters obtained from a plurality of metal filaments oxidized in close proximity to one another.
摘要:
A thin-walled monolithic iron oxide structure, and process for making such a structure, is disclosed. The structure comprises a monolithic iron oxide structure obtained from oxidizing a thin-walled iron-containing, preferably plain steel, structure at a temperature below the melting point of iron. The preferred wall thickness of the steel is less than about 0.3 mm. The preferred iron oxides of the invention are hematite, magnetite, and combinations thereof. The thin-walled structures of the invention have substantially the same physical shape as the iron starting structure. Thin-walled iron-oxide structures of the invention can be used in a wide variety of applications, including gas and liquid flow dividers, corrosion resistant components of automotive exhaust systems, catalytic supports, filters, thermal insulating materials, and sound insulating materials. Iron oxides of the invention consisting substantially of magnetite can be electrically heated and, therefore, can be applicable in applications such as electrically heated thermal insulation, electric heating of liquids and gases passing through channels, and incandescent devices. Additionally, combination structures using both magnetite and hematite can be fabricated.