Abstract: An alumina sorbent capable of adsorbing NOx and SOx from waste gases and being regenerated by heating above 600.degree. C. is made by incorporating an alumina stabilizing agent into the sorbent. A preferred method is to add the stabilizer when the alumina is precipitated. The precipitated powder is formed subsequently into a slurry, milled and dripped to form the stabilizing spheroidal alumina particles. These particles are impregnated with an alkali metal or alkaline earth metal to form the stabilized sorbent. Alumina stabilizers include one or more of silica, lanthana, other rare earths, titania, zirconia and alkaline earths.

Abstract: There is provided an improved electrically heatable catalytic converter formed of an electrically heatable corrugated thin metal monolith and having a collimator axially spaced upstream of the electrically heatable monolith, said collimator having the purpose of straightening and subdividing the gas flow to minimize the tendency of the leading edges of the corrugated thin metal monolith to be folded over in use.

Abstract: There is provided an improved electrically heatable core for an electrically heatable catalytic converter. The core is characterized by corrugated thin metal strips and flat thin metal strips in alternating relation with each other and secured to an electrically conductive central core or tube. Alternating with the corrugated thin metal strips and the flat thin metal strips are areas of brazing metal in an axially staggered pattern. These strips are spirally wound and fused to braze them together in a unified monolith. A retainer shell is supplied to hold the monolith together. The core is placed in a housing fitted with insulated means for conducting electric current to the monolith to effect heating. The housing is then inserted in an exhaust line where it is effective to control start-up pollution, and where the monolith is constrained against telescoping.

Abstract: There is provided a core element for an electrically heatable catalytic converter, and an electrically heatable catalytic converter containing the same, the core element being characterized by a corrugated thin metal foil strip, preferably herringbone corrugated, and in laminar relationship therewith, a flat thin metal foil strip of either stainless steel or brazing metal, or a combination of both, the flat thin metal foil strip having a width less than the width of the corrugated thin metal foil strip. The strips are then spirally wound, or accordion folded to form a monolith, and suitably connected to a voltage source to supply electrical power to the unit.

Abstract: A catalytic process for converting low molecular weight non-aromatic compounds into higher molecular weight aromatic compounds utilizes a unique zeolite catalyst with improved hydrocarbon conversion. The catalyst is a crystalline aluminosilicate having a SiO.sub.2 /Al.sub.2 O.sub.3 ratio greater than 5 and preferably a MFI or MEL zeolite. The zeolite contains a Group VIIIA metal, preferably nickel, and is subjected to thermal or hydrothermal treatments under controlled conditions of temperature, time or steam partial pressure so as to effect a decrease in the amount of carbon deposited as the zeolite catalyst. The catalyst can be used in a process for the conversion of light hydrocarbon feedstocks to improve aromatization activity.

Abstract: There is provided an electrically heatable catalytic monolith composed of a bundle of layers of corrugated thin metal strips in contiguous relation in an electrically parallel circuit, the bundle being accordion folded and having electrical contacts at each end of the bundle and insulation between contiguous folds of the bundle. There is also provided a catalytic converter having a housing, a nonelectrically heatable catalytic monolith and an electrically heatable catalytic monolith as above described in tandem relation in the housing. The primary purpose of the devices hereof is to enable preheating of the catalyst to near optimum temperature for catalytic treatment of a gas, e.g. exhaust gas from an internal combustion engine, to overcome pollution at the time of start-up of the engine and until equilibrium temperature of the unit is achieved.

Abstract: There is provided an electrically heatable catalytic converter insert for insertion in a current internal combustion engine exhaust line. The device described includes a housing and a polycellular corrugated thin metal foil monolith disposed therein, and having a central core. The monolith includes a noble metal catalyst disposed of the inner surface of the cells. There are also provided a positive terminal and a negative terminal for attachment to a voltage source. The positive terminal is attached to the central core, and the negative terminal is attached to the housing, the foil providing a heatable resistance member enabling heating of the device by electrical power. The positive and negative terminals are electrically insulated from each other and each has a radially projecting arm for attachment of cables from a voltage source.

Abstract: There is provided an improved core for an electrically heatable catalytic converter, and an electrically heatable catalytic converter containing such core, said core characterized by having a plurality of subcircuits in which the heater strips of thin high temperature resistive metal alloy are in parallel and connected between an outer shell segment and a central structural member, and the plurality of such subcircuits is connected in series, whereby the resistance between the terminals of the electrically heatable catalytic converter is effectively raised.

Abstract: A catalyst for control of hydrocarbon emission with improved resistance to phosphorus, sulfur, halogen and silicon poisoning comprising a refractory oxide support impregnated with 0.5 to 20% by weight chromium oxide or manganese oxide or a mixture thereof, and a catalytically effective amount of one or more platinum group metals. The preferred refractory oxide support is alumina. The preferred platinum group metals include Pt, Pd, Ir and Rh.

Abstract: Catalysts for the selective catalytic reduction of NOx by ammonia are made from porous formed supports having a certain fraction of the pores with pore diameters larger than 600 Angstrom units. Thus macropores can be introduced in a formed TiO.sub.2 support by adding burnout materials prior to forming the titania into the formed support. Then conventional DeNOx catalytic metals are added. Barium sulfate can be added to the surface of the porous inorganic oxide to make an improved support.

Abstract: Porous titania or zirconia spheres having a particle diameter of about 1 to 100 microns, a pore volume of about 0.1 to 1 cc/g, and a pore diameter in the range of about 10 to 5,000 Angstrom units are made by spray drying a slurry of ultimate titania or zirconia particles having a diameter about equal to that of the desired pore diameter of the formed sphere, and a reactive binder. The spheres can be used in high performance liquid chromatography columns and as catalyst supports.

Abstract: There is provided a core element, especially useful in fabricating an electrically heatable catalytic converter, which element comprises a thin stainless steel strip having an area on at least one surface coated with a masking alloy, especially a nickel-containing brazing alloy, and a contiguous area coated with a refractory metal oxide, e.g., alumina. This structure enables the production of catalytic cores exhibiting minimum voltage drop at the interconnections between foil laminae to be heated electrically.

Abstract: Catalysts which are suitable for auto exhaust use are made with a promoter oxide that is deposited in a concentration gradient. A solution of the promoter oxide precursor, e.g., cerous nitrate solution, is impreganted uniformly into the pore structure of a support which can be in the form of beads or extrudates to a level just below the full incipient wetness. The impregnated support is then treated with a gaseous base such as ammonia, under dynamic conditions such as tumbling (to insure uniformity), which causes the precipitation of the promoter oxide in the form of a radial concentration gradient. The resulting product is then dried and calcined at sufficiently high temperature to effect complete conversion of the promoter precursor to its oxide form, e.g., CeO.sub.2.

Abstract: Cracking catalysts which yield higher octane gasoline than conventional cracking catalysts are made with large pore size zeolites such as zeolite Beta and zeolite ZSM-20 in the low sodium, H.sup.+ form. These zeolites are mixed with a matrix which contains at least a binder and formed into catalyst particles. These catalysts are especially suitable to be used in fluid catalytic cracking.

Abstract: There is provided an improved electrically heatable core for an electrically heatable catalytic converter. The core is characterized by a plurality of corrugated thin metal strips secured to an electrically conductive central core or tube. Alternating with the corrugated thin metal strips are narrow strips of brazing metal in an axially staggered pattern. These strips are spirally wound and fused to braze them together in a unified monolith. A retainer shell is supplied to hold the monolith together. The core is placed in a housing fitted with insulated means for conducting electric current to the monolith to effect heating. The housing is then inserted in an exhaust line where it is effective to control start-up pollution, and where the monolith is constrained against telescoping.

Abstract: A catalytic converter includes a metal honeycomb catalyst support which is anchored in a canister so that it cannot telescope or blow out. The honeycomb catalyst support is made by folding a strip of metal back and forth upon itself. The lines of folding are inclined to the perpendicular to the axis of the strip. The repeating sequence of the inclinations is left, right, right, left, etc. Folding the strip in this manner produces a honeycomb that has a taper in both of two directions so that it can be anchored in the canister. The canister has a taper which coincides with the taper of the honeycomb. The invention also includes a method and apparatus for making crease lines on the strip, so that the strip can be folded.

Abstract: The accumulation of gaseous ammonia in areas wherein animals are housed or maintained is controlled by providing to the areas animal litter, bedding, or other absorbent material which contain a low molecular weight, non-volatile organic acid. Acids such as citric, malic, fumaric, phosphoric, tartaric, maleic, malonic, succinic, sorbic and mixtures of these acids are used and especially phosphoric and fumaric. These acids can be used in concentrations of about 0.0001 to 2 wt % of the dry bedding.

Abstract: An improved welding cup is made from graphite or ceramic fiber composites, coated with silicon nitride, sialon, boron nitride, or silicon carbide. The cup shows superior resistance to erosion, slagging, and thermal fracture.

Abstract: There has thus been provided a highly efficient metal-ceramic catalytic combustor for a gas turbine/catalytic combustor assembly. The catalyst zone is formed of a high temperature resistant metal wire mesh, e.g., palladium coated tungsten or ferritic stainless steel screen, e.g., 40 mesh, which is aluminized with metallic aluminum, and heated to convert the outermost layer of aluminum to aluminum oxide and encourage the diffusion of the inner layer of aluminum into the body of the metal wire, desirably forming a thin metal/aluminum alloy layer. The outer surface because of the Kerkendall Effect is porous and readily accepts and strongly bonds to a metal oxide coat, e.g., a magnesia/alumina, or magnesia/alumina/yttria, or barium oxide/alumina, or barium oxide/alumina/yttria wash coat. There may also be included a catalyst deposited on the ceramic outer coat, e.g., a noble metal catalyst, for enhancement of the combustion of an air/fuel mixture.

Abstract: A catalytic converter includes a metal honeycomb catalyst support which is anchored in a canister so that it cannot telescope or blow out. The honeycomb catalyst support is made by folding a strip of metal back and forth upon itself. The lines of folding are inclined to the perpendicular to the axis of the strip. The repeating sequence of the inclinations is left, right, right, left, etc. Folding the strip in this manner produces a honeycomb that has a taper in both of two directions so that it can be anchored in the canister. The canister has a taper which coincides with the taper of the honeycomb. The invention also includes a method and apparatus for making crease lines on the strip, so that the strip can be folded.