Abstract: A method for detection of the performance reduction of an exhaust gas purification catalyst used for reducing the concentration(s) of combustible components or (and) nitrogen oxides all present in an exhaust gas, which method detects a reduction in the heat amount E.sub.g generated from the exhaust gas by the reaction of the exhaust gas catalyzed by the catalyst, or a reduction in the cumulative heat amount generated from the exhaust gas by said reaction in a predetermined temperature range taken by the catalyst during its temperature increase. This method can detect the performance reduction of the catalyst accurately without conducting constant-speed vehicle running for a long time.

Abstract: A steam reformer for converting a reactor fuel into a product gas includes a segmented catalyst bed. The steam reformer side walls have a thermal coefficient of expansion which is greater than the thermal coefficient of expansion of the catalyst. By forming low volume catalyst bed segments in the hotter portions of the catalyst bed, slumping and subsequent damage of the catalyst pellets is minimized. The catalyst bed is divided into segments whose volumes are inversely proportional to the temperatures of the various zones in the reformer. The segments are formed by utilizing sequential catalyst support assemblies which include perforated catalyst support members that are differentially spaced apart from each other by support assembly legs having varying lengths. Catalyst support assemblies with shorter length legs are used in the hotter zones of the reformer, and support assemblies with progressively longer length legs are used in the cooler zones of the reformer.

Abstract: An improved catalyst assembly for vapor/liquid contact towers. Catalyst media used to promote chemical reactions is secured substantially in the liquid phase of the tower, such as in the lower portion thereof for improving mass transfer efficiency. Unlike previous process tower assemblies, wherein distillation in conjunction with chemical reaction occurs in the vapor phase or in a mixed phase, the present invention substantially confines the reaction step to the liquid phase. In this manner, the reaction is less obstructive to vapor flow within the tower, promoting better mixing and diffusion of the feed components.

Abstract: A process wherein a liquid influent stream containing such an amount of a reactant that decomposition thereof to a desired concentration evolves, at the prevailing pressure and temperature, at least 0.5 volumes of gas per volume of the influent stream, is continuously passed through a volume of a particulate catalyst that is sufficient to decompose said reactant to said desired concentration and the evolved gas rises to the surface of said liquid and disengages therefrom into a gas space above said liquid, thereby providing an effluent stream having said desired concentration of said reactant.

Abstract: This invention relates to a method of conducting a chemical reaction in the presence of a heterogeneous catalyst, in which a feedstock is passed through a catalytic reactor, said reactor comprising a solid reactor bed with a catalytically active material present thereon, and at least one heat supplying and/or discharging reactor wall, and in which the catalyst bed consists of elementary particles of material sintered together and to one side of the wall, there being no sintered material present on the other side of the reactor wall, and in which the maximum distance in meters (x.sub.

Abstract: The novel process of the invention produces chlorine dioxide by feeding an aqueous solution of chloric acid to a chlorine dioxide generator. The aqueous solution of chloric acid is reacted with a reducing agent in the chlorine dioxide generator to produce chlorine dioxide and a spent chloric acid solution containing metallic impurities. A portion of the spent chloric acid solution containing metallic impurities is reacted with a basic compound selected from the group consisting of alkali metal hydroxides, and alkali metal carbonates in a neutralizing zone to form a precipitate of the metallic impurities and an alkali metal chlorate solution. The precipitate of the metallic impurities is separated from the alkali metal chlorate solution and the alkali metal chlorate solution fed to an ion exchange compartment of an electrolytic cell having an anode compartment, a cathode compartment, and at least one ion exchange compartment between the anode compartment and the cathode compartment.

Abstract: Highly active amorphous alloy catalysts for use in decomposing of flons into hydrofluoric acid, hydrochloric acid and carbon dioxide by the reaction of flons with water, consist of at least one element selected from the group of Ni and Co, at least one element selected from the group of Nb, Ta, Ti and Zr, which are effective for the formation of the amorphous structure by coexisting with at least one element selected from the group of Ni and Co, and at least one element selected from the group of Ru, Rh, Pd, Ir and Pt, which are necessary for the high catalytic activity. The alloys are activated by immersion into hydrofluoric acids.

Abstract: A process is disclosed which comprises: contacting a catalyst such as alumina silica, aluminosilicates, titanium oxide, magnesium oxide, and the metals of Groups III and IIB of the Periodic Table under reducing conditions with a gaseous mixture comprising elemental chlorine gas and a diluent under conditions effective to improve the ability of the catalyst to dehydrohalogenate halogenated hydrocarbons: contacting the catalyst with a halogenated hydrocarbon feedstock, the halogenated hydrocarbon feedstock with or without a carrier gas, in the gas phase under dehydrohalogenation conditions; and recovering a dehydrohalogenated product.

Abstract: Multilobar shaped catalyst particulates, e.g., tri- or quadrilobar particulates, well adapted for the catalytic conversion of gases containing compounds of sulfur, e.g. SO.sub.2, H.sub.2 S, COS and/or CS.sub.2, by the Claus reaction and/or by hydrolysis, are comprised of a catalytically effective amount of values catalytically active in the Claus reaction and/or reactions entailing hydrolysis of organosulfur compounds.

Abstract: A catalytic chemical process is carried out non-adiabatically using as a catalyst a body with two sets of channels throughout the body. One set of channels leads the process fluid towards one of two parallel walls of the catalyst chamber, the other set towards the outer wall, In slits between walls and catalyst heat is exchanged between process fluid and at least one of these walls upon reflecting the process fluid leaving channels of one set and entering channels of the other. The body may be made of alternatingly corrugated and plane sheets using in turn two different orientations for the corrugated sheets. It is preferred that the sheets are arranged orthogonal to the heat transmitting wall(s) and parallel to the overall direction of flow. The method is preferred for endothermic processes, especially steam reforming of hydrocarbon(s).

Abstract: A recirculating fiber filter (1) and method is provided for removing particulates from moving fluid streams. High aspect ratio fibers (2) are used which readily nest with each other to form the high voidage fiber filter bed. In the method, fibers are continuously removed from the bottom of the bed regenerated to remove particulates and recycled back to the top of the bed and distributed thereon. Dirty fluid is passed from the top to the bottom of the filter. Dendrites of the particulate impurity appear to buildup in a thin section (A) at the top of the filter and provide the primary mechanism for further particulate entrapment. Recirculation of fibers offers a continuously fresh volume of fibers at the top for capture of particulates.

Abstract: Apparatus for catalytically reducing noxious substances in flue gas employes, in a first embodiment wherein combustion air is also pre-heated, a two-part heat-exchanger which is traversed from top to bottom by a plurality of catalytically active, separately movable heat-storage elements. Combustion gas is heated in a first portion of the heat-exchanger by heat transferred from the heat-storage elements and the noxious gases are catalytically reduced in a second portion of the heat-exchanger downstream from the first portion in the presence of ammonia and the heat-storage elements. The heat-storage elements can be removed from circulation and replaced by unspent or regenerated elements when the residual content of noxious substances in the flue gas remains elevated.

Abstract: In order to clean gases containing noxious components by contacting the gases with a solid material layer adhering to carrier bodies, the solid material layer is applied to the carrier body by wetting with an impregnating solution and then drying the solution on the carrier bodies. After being used up by reaction with the gases to be cleaned, the solid material layer is removed from the carrier bodies, after which it can be replaced by wetting with impregnating solution and drying again. The carrier bodies are stationary and the impregnating solution is trickled over them. Once the carrier bodies are wetted, irrigation with the impregnation solution is interrupted and the solution is dried on the carrier bodies. When the gas reaction at the solid material layer thus formed weakens, the stationary carrier bodies are re-irrigated with impregnation solution and dried. After many repeated impregnations the solid material layer is washed away by flushing or flooding the carrier bodies with a wash solution.

Abstract: A molded catalyst for fitting into a reactor vessel having an inlet and an outlet for a reactant gas, the catalyst having openings therethrough parallel to the direction of a reactant gas which is introduced into the reactor vessel from the inlet, the catalyst comprising: a wear-resistant front surface facing the inlet of the reactor vessel and a continuation of the front surface extending therefrom, the both being the front portion of the catalyst, and the remaining part of the catalyst made so wear-susceptible as to have either:(a) a wearability of 2-10% in a shaking abrasion test wherein grinding particles having an average particle size of 100 .mu.m and a Mohs scale of 9 are placed in the openings of the catalyst in an amount of 50% by volume based on the total volume of the openings, and the catalyst is shaked for three hours with an amplitude of 77 mm and a frequency of 320 per minute; or(b) a wearability of 7.

Abstract: The invention relates to a reactor for industrial plants, e.g. for an ammonia synthesis plant, comprising several catalyst beds in series charged by a radial gas flow. The object is to provide for a uniform gas flow through the catalyst bed along its entire height, otherwise different space velocities are experienced within the catalyst bed involving irregularities in the reaction. The problem is solved when the cross-section of the annular space for the effluent reaction gas flowing in axial direction is equal to or larger than the cross-section of the annular space for the influent fresh gas flowing in axial direction.

Abstract: A process for the catalytic gaseous phase reaction of a reactive gas wherein the heat of reaction generated produces a temperature elevation of less than about 150.degree. C. in the substantially adiabatic reaction system, the improvement comprising:heating the cold reactive gas by passing it through a heated regenerative material present in the first portion of a vessel;passing the heated reactive gas through a solid catalyst for the reaction present in a second portion of the vessel to form a gaseous product stream;redirecting the gaseous product stream;passing the redirected gaseous product stream through the solid catalyst for the reaction present in the second portion of the vessel to form additional gaseous product,cooling the gaseous product stream by passing it through a cooled regenerative material present in the first portion of the vessel; andperiodically reversing the flow direction in the portions of the reaction system.

Abstract: An apparatus and process for catalytically reducing noxious substances in flue gas wherein a heat exchanger is traversed from a top section to a bottom section by a plurality of heat storage elements which are separately movable and are charged by the flue gas transversely to their direction of movement. At least a portion of the heat storage elements are provided with a catalyst coating. Flue gas cooled downstream of a desulfurization system is conducted through the bottom section of the heat exchanger where it is preheated by the heat storage elements and is then heated to a predetermined reaction temperature by an external heating means. Ammonia is added and the flue gas is conducted at least once through at least one middle section of the heat exchanger for the catalytic reduction of the noxious substances. Then, the flue gas is conducted through the top section of the heat exchanger so as to cool it to a predetermined chimney entrance temperature.

Abstract: An extrudate catalyst suitable for auto emission control is made from a solid, transitional alumina with a partially hollow interior. Deposited on the extrudate are two promoters, ceria and an alkali metal, and one or more platinum group metals. The preferred alkali metal is in the oxide form as lithia. The cylindrical extrudate has internal reinforcing vanes or ribs extending from the inner wall to the center of the extrudate particle. This configuration permits the catalyst to have the large geometric surface area per reactor volume yet, because of the openings inside the extrudate, the catalyst particles do not exhibit a large pressure drop when packed in a deep bed. These catalysts provide greater hydrocarbon and carbon monoxide conversions than do similar size spherical particles and they have improved light-off characteristics.

Abstract: An extrudate catalyst suitable for auto emission control is made from a solid, transitional alumina. It has a partially hollow interior and one or more platinum group metals deposited on the extrudate. The cylindrical extrudate has internal reinforcing vanes or ribs extending from the inner wall to the center of the extrudate particle. This configuration permits the catalyst to have the large geometric surface area per reactor volume yet, because of the openings inside the extrudate, the catalyst particles do not exhibit a large pressure drop when packed in a deep bed. These catalysts provide greater hydrocarbon and carbon monoxide conversions than do similar size spherical particles and they have improved light-off characteristics.

Abstract: Saline source water containing dissolved oxygen is deoxygenated to form injection quality water in the disclosed process and apparatus. In accordance with the invention, saline source water is electrolyzed in an electrolytic cell which produces hydrogen and chlorine. The hydrogen is reacted with the dissolved oxygen in a catalyst resin bed to reduce the dissolved oxygen to the desired level. Optionally, evolved chlorine may be used as a biocide in the system.

Abstract: Process and system for cooling a reaction effluent containing volatized catalyst wherein the effluent is contacted with circulating cooled solid catalyst in dilute phase transport contact, with the volatized catalyst being condensed onto the solid catalyst.

Abstract: A method is provided for preparing a porous catalyst carrier having a pore volume of at least 0.5 cc/g, a content of micropores in which the pore diameter is between 80 and 150 A. which constitutes at least 70% of the pore volume and a content of macropores which constitutes less than 3% of the pore volume. In the method, a powdered solid comprised of predominantly alpha-alumina monohydrate and sized in the range below 500 microns is treated with a particular amount of a monobasic acid. The acid in the resulting mixture is then at least partially neutralized by admixing with a nitrogen base such as aqueous ammonia. The treated and neutralized feed is converted into a catalyst carrier by shaping as desired, drying, and calcining. Further aspects of the invention are a hydrodesulfurization catalyst prepared using the present carrier and a hydrodesulfurization process for metals-contaminated hydrocarbon feeds using the catalyst.

Abstract: In a method for treating a gas containing dusts therein under a monolithic catalyst consisting of a ceramic support which is substantially porous throughout the structure, and has active ingredients uniformly dispersed therein and passages therethrough parallel to the flow of the gas for allowing the gas to pass therethrough, the improvement in which the catalyst has the sintered front portion or has a vitreous coating on the front portion. Alternatively, the improvement in which a metal or sintered ceramic lid having openings therethrough is fixed onto the front face of the catalyst with the passages in alignment with the openings of the lid.

Abstract: An improved method for the oxidation of water-soluble inorganic sulfide ions in aqueous systems is disclosed. The method uses a soluble metallic ion catalyst in the presence of an oxidizing agent. The improvement comprises adding to the system a water-soluble anionically-charged polymer having a molecular weight of from 1,000-100,000. Additionally, certain organic phosphonate materials can be used in combination with the polymer.By the use of the polymer or polymer-phosphonate treatment the efficiency of the metallic ion catalyst and the sulfide oxidation step is improved.

Abstract: Fines are removed from a fines-containing fluid by fluidizing a bed of fluidizable solids with the fines-containing fluid at conditions avoiding fluid spouting at the bed surface, the bed solids being preferably at least two orders of magnitude greater in size than the particles, and being coated with a substance whose stickiness changes during its residence time in the bed. Particles adhere to the transiently sticky solids and can be recovered for re-use. Useful for cleaning dusty gases and recovering catalyst from cracker flue gas.

Abstract: A filter house (12) employing a selective catalytic reduction process for removing NO.sub.x emissions from a flue gas stream while simultaneously filtering out and collecting entrained particulate matter from the stream. Accordingly, the filter house (12) includes flue gas inlet and outlet passages (18, 30) and a plurality of porous filter bags. The bags are treated with a suitable catalyst to facilitate the selective catalytic reduction process.

Abstract: Methods and apparatus pertaining to reduction of sodium sulfate to sodium sulfide include the feeding of sodium sulfate into a combustion chamber in which the sodium sulfate is exposed to a reducing atmosphere while at the same time being exposed also to a temperature above the melting point of sodium sulfide. Thus, a liquid accumulates at the bottom of the combustion chamber and this liquid will of course contain a considerable amount of sodium sulfide reduced from the sodium sulfate.

Abstract: During use of a contact apparatus to remove harmful components, such as sulfur and nitrogen oxides, from waste gas, dust particles are deposited on the interior of the gas-solid contact zone and reduce efficiency of the apparatus. The dust particles can be removed by passing through the contact apparatus a current of a carrier gas supporting solid particles of, for example, siliceous sand. The particles have a diameter of 50 to 2000 .mu.m and the actual linear velocity of the carrier gas in the gas-solid contact zone is from 2 to 15 m/sec. The carrier gas can be the waste gas itself so that dust removal can be carried out without interrupting use of the apparatus. The solid particles can be removed from the carrier gas and recycled for further dust removal.

Abstract: An improved reactor for chemical reaction includes a wetproofed catalyst therein for increasing the rate of reaction between the reactants and/or controlling selectivity of the products, if there is more than one reaction product. The wetproofed catalyst may be used in addition to the other catalytic systems already known in the art. The reaction occurs in the presence of two or more fluid phases. The types of reaction may be reduction-oxidation, hydration and the like. The wetproofed catalyst is a solid, particulate catalyst including surface portions which are wetproofed so that the catalyst is not flooded by any of the reactants, reaction products or other fluids in the reaction chamber. Wetproofing of the surface portions of the catalyst may be accomplished in various ways, as described, and various materials may be used for the catalyst.