Abstract: A system and method for removing sulfur-containing contaminants from indoor air includes a panel system having a first layer and a second layer. The first layer can include a base media onto which sodium bicarbonate is attached. The second layer can include a base media onto which activated carbon is attached. Indoor air including sulfur-containing contaminants can contact and pass through the first layer. Sulfuric acid can react with the sodium bicarbonate to produce sodium sulfate, which can, in turn, act as a drying agent for organic sulfur-containing contaminants in the indoor air, such as carbon disulfide and carbonyl sulfide. As a result of such drying, the second layer can more effectively trap and/or bind (adsorb) the organic sulfur-containing contaminants so that these contaminants are removed from the contaminated air. The treated air can be returned to an indoor space of the structure.

Abstract: This invention involves highly porous, stable metal oxide felt materials that are used as catalytic supports for a number of different applications including dehydrogenation of light paraffins to olefins, selective hydrogenation of dienes to olefins, hydrogenation of carboxylic acids, oxidation or ammoxidation reactions, epoxidation of light olefins and removal of sulfur compounds from gas streams.

Abstract: This invention relates to a catalyst material, and its method of making and manufacture, useful for a diversity of chemical production processes as well as various emission control processes. More specifically, it relates to a catalyst composition, preferably comprising a metal oxide felt substrate, with one or more functional surface active constituents integrated on and/or in the substrate surface, which can be used in the removal of sulfur and sulfur compounds from hot gases as well as acting to trap solid particulates and trace metals within these hot gases.

Abstract: A controller is provided for directing control of a process performed to control an amount of a pollutant emitted into the air. The process has multiple process parameters (MPPs) The controller includes either a neural network process model or a non-neural network process model. Whichever type model is included, it will represent a relationship between one of the MPPs and other of the MPPs. The controller also includes a control processor having the logic to determine the validity of a measured value of the one MPP based on the one model. The control processor directs control of the process in accordance with the measured value of the one MPP only if the measured value of the one MPP is determined to be valid. On the other hand, if the measured value is determined to be invalid, the control processor may direct control of the process in accordance with an estimated value of the one MPP.

Abstract: This disclosure relates generally to processes for efficient incineration and conversion of the tail gas streams from sulfur recovery units containing sulfur compounds such as H2S, CO2, COS, CS2, and other sulfur species and sulfur vapors from S1 to S8 to SO2. The present disclosure describes the use of a combination of catalysts to achieve efficient oxidation of all reduced sulfur compounds as well as oxidation of CO and H2 to meet the industry emission requirements. The catalytic tail gas incineration process described herein can advantageously operate at lower temperatures, which in turn can represent a savings in reduced fuel gas costs.

Abstract: Disclosed is a composition useful in the hydrolysis of sulfur compounds that are contained in a gas stream. The composition comprises alumina, a group VI metal component and a group VIII metal component. The composition has a pore structure such that a large percentage of its total pore volume is contained within the pores having a pore diameter greater than 10,000 angstroms.

Abstract: A method for desulfurizing natural gas includes contacting the natural gas with an adsorbent which preferentially adsorbs at least one of hydrogen sulfide, COS, sulfur odorants, or combinations thereof, at a selected temperature and pressure, thereby producing desulfurized natural gas and an at least one of hydrogen sulfide/COS/sulfur odorant/combinations thereof-rich adsorbed component. The adsorbent includes a copper species adapted to form ?-complexation bonds and direct metal-sulfur bonds with the at least one of hydrogen sulfide, COS, sulfur odorants, or combinations thereof, and wherein the preferential adsorption occurs by ?-complexation and direct metal-sulfur bonding.

Abstract: To provide an SO3 reduction catalyst for purifying an exhaust gas capable of efficiently reducing the amount of SO3 that is present in a combustion exhaust gas and is a starting substance of S-containing substances such as acid ammonium sulfate causing deterioration of performance of the catalyst or corrosion of apparatuses disposed downstream of the catalyst, or capable of controlling the generation of SO3 in the catalyst itself; a preparation process of the catalyst; and an exhaust gas purifying method using the catalyst. In the catalyst for purifying a combustion exhaust gas containing nitrogen oxides, 50 wt. % or greater of the amount of Ru and/or Ir to be supported is adjusted to fall within a depth of 150 ?m from the surface layer of a substrate; and the catalyst is prepared by immersing the substrate in a metal colloid solution of Ru and/or Ir to be supported or an aqueous solution containing at least one compound selected from compounds of Ru and/or Ir to be supported.

Abstract: Process for removing sulfur oxides, mercury vapor, and fine particulate matters from industrial flue gases that contain such pollutants. Pollutants are removed by modules, which contain microporous adsorbent (i.e., sorbent) material held within a polymer matrix. The composite material that contains the microporous absorbent material held within a polymer matrix removes sulfur oxides by converting them into high concentration sulfuric acids. SULFURIC acid produced inside the composite material is automatically expelled onto the external surfaces of the composite material and is drained into an acid reservoir together with the fine particulate mailers which are washed from the external surfaces of the composite material by the constant dripping of the sulfuric acid along the external surfaces of the composite material.

Abstract: The present invention relates to a catalyst support material and catalysts made therefrom having improved resistance towards erosion. The catalyst support contains at least 20% by weight of TiO2 being present mainly in the anatase form. Furthermore, the catalyst support contains diatomaceous earth in an amount of at least 2% and less than 80% by weight of the catalyst support. In one embodiment catalysts made from said catalyst support contain oxides or sulfates of base metals from the group of V, W, Mn, Nb, Mo, Ni, Fe or Cu. Another option is a catalyst prepared from said catalyst support containing Pt or Pd. Said catalysts are used for treatment of a flue gas. More specifically the catalyst supports prepared according to the present invention and showing improved resistance towards erosion are used in flue gas containing a large amount of particulate matter and for selective catalytic reduction of nitrous oxides.

Abstract: Systems and processes for removing a first sulfur compound from a hydrocarbon stream. The systems and process utilize at least one reaction vessel incorporating a hydrolysis catalyst suitable for hydrolyzing the first sulfur compound to a second sulfur compound. The reaction vessel also incorporates a sorbent material suitable for absorbing the second sulfur compound. Following hydrolysis of the first sulfur compound to the second sulfur compound and absorption of the second sulfur compound, a hydrocarbon-containing stream having a reduced sulfur content is produced. The hydrolysis catalyst and sorbent material may be provided in separate zones within the reaction vessel or provided as a mixture in a single zone. The hydrocarbon-containing stream having a reduced sulfur content is suitable for a variety of uses, including as a feedstreams for hydrogen plants, process gas streams for power generation plants, or for other uses for hydrocarbon-containing stream having reduced sulfur content.

Abstract: Anionic clay compounds such as hydrotalcite-like compounds can be made by a process wherein a non-hydrotalcite-like compound (or a hydrotalcite-like compound) are heat treated and then hydrated to form hydrotalcite-like compounds having properties (e.g., increased hardness and/or density) that differ from those of hydrotalcite-like compounds made by prior art methods wherein non-hydrotalcite-like compounds (or hydrotalcite-like compounds) are not similarly heat treated and hydrated to form such hydrotalcite-like compounds.

Abstract: Process for the removal of organic and/or inorganic sulfur from an ammonia stream by passing said stream through a fixed bed of sulfur absorbent in a sulfur absorber and withdrawing a sulfur-free ammonia stream, wherein said sulfur absorbent is a catalyst having a total nickel content in reduced form in the range 10 wt % to 70 wt % with the balance being a carrier material selected from the group of alumina, magnesium alumina spinel, silica, titania, magnesia, zirconia and mixtures thereof.

Abstract: A process for the selective removal of sulphur compounds from synthesis gas being rich in carbon monoxide and containing hydrogen, carbon monoxide and containing hydrogen, carbon dioxide and steam comprising contacting the synthesis gas at a maximum contact temperature of 100° C. with an absorbent comprising Cu/ZnO compounds and being prepared by thermal decomposition of a corresponding carbonate and activation of the thermal decomposed carbonate with a reducing gas.

Abstract: A fixed bed containing a particulate catalyst or sorbent material (10) subject to operation at high temperature having a shaped boundary member (16) inclined to the direction of fluid flow through the bed that maintains the depth of said catalyst or sorbent at the boundary of the bed through a series of thermal expansion-thermal contraction cycles is described. By maintaining bed depth, the shaped boundary member (16) can prevent bypass of, e.g. ammonia through a bed of particulate ammonia oxidation catalyst.

Abstract: Recovering sulfur from a gas stream containing hydrogen sulfide by oxidizing the gas stream to convert the hydrogen sulfide in the gas stream to sulfur oxide, and thus form a sulfur oxide enriched gas stream. The sulfur oxide enriched gas stream is contacted with a solid, sulfation resistant adsorbent bed at relatively low temperatures to extract the sulfur oxides and retain them as sulfur compounds, thus forming a sulfur oxide depleted gas stream. The adsorbent bed is then contacted with an inert or reducing gas stream to reduce the retained sulfur compounds to sulfur and/or sulfur dioxide and thereby form an enriched sulfur and/or sulfur dioxide bearing stream. The elemental sulfur is recovered and/or the sulfur dioxide bearing stream may be recycled to the Claus unit for further conversion.

Abstract: Carbon monoxide and carbonyl sulfide emissions are reduced in manufacturing processes, including titanium tetrachloride production processes. Gas is contacted with CO, COS, and an oxygen-containing gas with a suitable catalyst. The catalyst may be a metal oxide catalyst containing bismuth, cobalt and nickel, a xerogel or aerogel catalyst containing Au, Rh, Ru and Co in aluminum oxide/oxyhydroxide matrices, or a supported metal catalyst that contains at least one metal from the group Pd, Rh, Ru and Cu. In the latter case, the catalyst support is contains alumina or carbon. A catalyst composite of Au, Rh, Ru and Cr, and cerium oxide and lanthanum oxide may also be used.

Abstract: Fluorine compounds such as C2F6, CF4, CHF3, SF6 and NF3, are made to contact with a fluorine compound decomposition catalyst and a catalyst for the decomposition of at least one of CO, SO2F2 and N2O in the presence of water or in the presence of water and oxygen. The catalyst for the decomposition of at least one of CO, SO2F2 and N2O preferably contains at least one selected from Pd, Pt, Cu, Mn, Fe, Co, Rh, Ir and Au in the form of a metal or an oxide. According to the invention, the fluorine compound can be converted to HF, which can be absorbed by water or an alkaline aqueous solution. Furthermore, a substance such as CO, SO2F2 and N2O which is formed by decomposition of the fluorine compound can also be decomposed.

Abstract: The current invention provides systems and method for reducing emissions of gaseous pollutants such as carbon monoxide, nitric oxide and nitrogen dioxide. The invention utilizes at least one catalyst bed and at least one fluidizable bed of sorbent material. The current invention provides for regeneration of the sorbent material without interrupting the catalytic reaction.

Abstract: High capacity sulfur oxide absorbents utilizing manganese-based octahedral molecular sieve (Mn—OMS) materials are disclosed. An emissions reduction system for a combustion exhaust includes a scrubber 24 containing these high capacity sulfur oxide absorbents located upstream from a NOX filter 26 or particulate trap.

Abstract: Anionic clay compounds such as hydrotalcite-like compounds can be made by a process wherein a non-hydrotalcite-like compound (or a hydrotalcite-like compound) are heat treated and then hydrated to form hydrotalcite-like compounds having properties (e.g., increased hardness and/or density) that differ from those of hydrotalcite-like compounds made by prior art methods wherein non-hydrotalcite-like compounds (or hydrotalcite-like compounds) are not similarly heat treated and hydrated to form such hydrotalcite-like compounds.

Abstract: A hydrocarbon gas such as methane and LPG is desulfurized in the presence of oxygen and an oxidation catalyst to convert sulfur compounds in the gas to sulfur oxides. The sulfur oxides are then trapped downstream of the oxidation by an adsorbent. The amount of oxygen added to the hydrocarbon gas to promote oxidation is such that the sulfur compounds are selectively oxidized and the oxidation of the hydrocarbon gas is minimized to reduce hydrogen formation.

Abstract: A process for removing hydrogen sulfide, other sulfur-containing compounds and/or sulfur and mercury from a gas stream contaminated with mercury, hydrogen sulfide or both. The method comprises the step of selective oxidation of hydrogen sulfide (H2S) in a gas stream containing one or more oxidizable components other than H2S to generate elemental sulfur (S) or a mixture of sulfur and sulfur dioxide (SO2). The sulfur generated in the gas stream reacts with mercury in the gas stream to generate mercuric sulfide and sulfur and mercuric sulfide are removed from the gas stream by co-condensation.

Abstract: A method is provided for removal of sulfur gases and recovery of elemental sulfur from sulfur gas containing supply streams, such as syngas or coal gas, by contacting the supply stream with a catalyst, that is either an activated carbon or an oxide based catalyst, and an oxidant, such as sulfur dioxide, in a reaction medium such as molten sulfur, to convert the sulfur gases in the supply stream to elemental sulfur, and recovering the elemental sulfur by separation from the reaction medium.

Abstract: A gas stream containing at least one fluorine compound selected from the group consisting of compounds of carbon and fluorine, compounds of carbon, hydrogen and fluorine, compounds of sulfur and fluorine, compounds of nitrogen and fluorine and compounds of carbon, hydrogen, oxygen and fluorine is contacted with a catalyst comprising at least one of alumina, titania, zirconia and silica, preferably a catalyst comprising alumina and at least one of nickel oxide, zinc oxide and titania in the presence of steam, thereby hydrolyzing the fluorine compound at a relatively low temperature, e.g. 200°-800° C., to convert the fluorine of the fluorine compound to hydrogen fluoride.

Abstract: The present invention relates to a layered catalyst composite useful for reducing contaminants in exhaust gas streams, especially gaseous streams containing sulfur oxide contaminants. More specifically, the present invention is concerned with improved catalysts of the type generally referred to as “three-way conversion” catalysts. The layered catalysts trap sulfur oxide contaminants which tend to poison three-way conversion catalysts used to abate other pollutants in the stream. The layered catalyst composites of the present invention have a sulfur oxide absorbing layer before or above a nitrogen oxide absorbing layer. The layered catalyst composite comprises a first layer and a second layer. The first layer comprises a first support and at least one first platinum component. The second layer comprises a second support and a SOx sorbent component having a free energy of formation from about 0 to about ?90 Kcal/mole at 350° C.

Abstract: A gas refining method for adsorbing a reducing gas obtained by pressure gasification of coal or oil comprises introducing a reducing gas stream into an adsorbing and removing zone where it contacts an adsorbent. Sulfur-containing compounds are adsorbed onto the adsorbent and a first oxygen-containing gas stream is introduced into the adsorbing and removing zone in order to form a regeneration gas containing sulfur dioxide. The regeneration gas is contacted with a second oxygen-containing stream and a calcium-containing liquid slurry to effect absorption of sulfur dioxide by the slurry and precipitation of a gypsum compound. The temperature of the slurry is varied to cause selective precipitation of 60 -gypsum hemihydrate or gypsum dihydrate.

Abstract: A gas stream containing at least one fluorine compound selected from the group consisting of compounds of carbon and fluorine, compounds of carbon, hydrogen and fluorine, compounds of sulfur and fluorine, compounds of nitrogen and fluorine and compounds of carbon, hydrogen, oxygen and fluorine is contacted with a catalyst comprising at least one of alumina, titania, zirconia and silica, preferably a catalyst comprising alumina and at least one of nickel oxide, zinc oxide and titania in the presence of steam, thereby hydrolyzing the fluorine compound at a relatively low temperature, e.g. 200°-800° C., to convert the fluorine of the fluorine compound to hydrogen fluoride.

Abstract: Active alumina catalysts, well suited for the Claus reaction, for the hydrolysis of organosulfur compounds and for catalytically removing objectionable sulfur compounds from gaseous effluents comprised thereof, contain a cocatalytically effective amount of sodium values, such effective amount, expressed by weight of Na2O, ranging from 1,200 ppm to 2,700 ppm.

Abstract: In the embodiments described in the specification, a spark-ignited internal combustion engine has an exhaust line containing an oxide gas absorber for absorbing NOx and SOx and desorbing NOx and SOx at elevated temperatures. The support member for the oxide gas absorber is a metal foil or a thin walled ceramic support to permit rapid heating and is coated with a layer of a gas absorbing material at least 50 microns thick to permit longer intervals between regeneration, thereby providing effective storage of oxide gases even with fuel consumption-optimized engines.

Abstract: The present invention relates to sulfur tolerant catalyst composites useful for reducing contaminants in exhaust gas streams, especially gaseous streams containing sulfur oxide contaminants. More specifically, the present invention is concerned with improved NOx trap catalysts for use in diesel engines as well as lean burn gasoline engines. The sulfur tolerant NOx trap catalyst composites comprise a platinum component, a support, and a NOx sorbent component prepared by hydrothermal synthesis. The NOx sorbent component comprises a first metal oxide and a second metal oxide. The metal in the first metal oxide is selected from the group consisting of aluminum, titanium, zirconium, silicon, and composites thereof, and the metal in the second metal oxide is selected from the group consisting of Group IIA metals, Group II metals, Group IV metals, rare earth metals, and transition metals. The metal in the first metal oxide is different from the metal in the second metal oxide.

Abstract: A catalytic composition and method of making the same in which a catalytic material has an average pore size distribution sufficiently large to substantially prevent capillary condensation.

Abstract: A process for oxidizing environmentally harmful compounds which participate in atmospheric photochemical reactions to produce for example ozone and undesirable smog constituents from a fluid, in particular a gas, volatile organic compounds (VOC) including hydrocarbons, CO and any other constituent that participates in atmospheric photochemical reactions to produce for example ozone or smog constituents and combustible compounds to be removed from a gas stream for reasons of toxicity, photochemical reactivity or physical discomfort such as irritants, particulates, odor sources and so on, and compounds which may cause upper atmosphere ozone depletion or lower atmosphere ozone formation. The uncoated randomly oriented mesh-like structure preferably has a porosity greater than about 85%. The coated randomly oriented mesh-like structure preferably has a porosity greater than about 65%.

Abstract: The attrition resistance of sorbent compositions are enhanced by controlling the pH of the support mixture containing the initial ingredients of the sorbent support. Desulfurization of a sulfur-containing fluid, such as cracked gasoline or diesel fuel, is enhanced by employing a co-feed gas comprising from about 80 to about 97 volume percent hydrogen.

Abstract: A process and system is disclosed for removing sulfur from tail-gas emitted from a Claus sulfur recovery process. First, the tail-gas is oxidized so as to convert sulfur therein to sulfur oxides. Oxidized tail-gas is directed into an absorber where a solid absorbent absorbs substantially all the sulfur oxides thereon. After allowing sufficient time for a desired amount of sulfur oxides to be absorbed, absorption is ceased. Next, the solid absorbent containing the absorbed sulfur oxides is contacted with a reducing gas so as to release an off gas containing hydrogen sulfide and sulfur dioxide. Upon releasing sulfur from the solid absorbent, the solid absorbent is regenerated and redirected into the absorber. Sulfur in the off gas emitted by regeneration is concentrated to an extent sufficient for use within a Claus sulfur recovery process for conversion to elemental sulfur.

Abstract: A gas mixture comprising molecular oxygen and 15 to 60 vol-% SO2 flows through a first catalyst layer which contains a catalyst containing vanadium pentoxide, and directly subsequently through a second catalyst layer which contains a catalyst containing iron. With an inlet temperature of 350 to 600° C., the gas mixture is introduced into the first catalyst layer which contains a granular V2O5 catalyst and 20 to 80 wt-% catalytically inactive inert material. Directly subsequently, the gas mixture is introduced into the second catalyst layer with a temperature of 500 to 750° C. Preferably, the catalyst of the second catalyst layer contains 3 to 30 wt-% arsenic oxide. There is produced an SO3-containing product gas with a volume ratio of SO2: SO3 of not more than 0.1.

Abstract: An integrated lean NOx trap. The integrated lean NOx trap includes a lean NOx trap containing a composite metal oxide mixture consisting essentially of about 80-100 wt % stoichiometric spinel MgAl2O4 and between about 0-20 wt % of CeO2 or CeO2—ZrO2. A method for removing NOx and SOx impurities from exhaust gases using the integrated lean NOx trap is also described.

Abstract: The present invention relates to sulfur tolerant catalyst composites useful for reducing contaminants in exhaust gas streams, especially gaseous streams containing sulfur oxide contaminants. More specifically, the present invention is concerned with improved NOx trap catalysts for use in diesel engines as well as lean burn gasoline engines. The sulfur tolerant NOx trap catalyst composites comprise a platinum component, a support, and a NOx sorbent component prepared by hydrothermal synthesis. The NOx sorbent component comprises a first metal oxide and a second metal oxide. The metal in the first metal oxide is selected from the group consisting of aluminum, titanium, zirconium, silicon, and composites thereof, and the metal in the second metal oxide is selected from the group consisting of Group IIA metals, Group III metals, Group IV metals, rare earth metals, and transition metals. The metal in the first metal oxide is different from the metal in the second metal oxide.

Abstract: Method for cleaning the atmosphere by adsorbing pollutants, e.g., hydrocarbons, ozone, carbon monoxide, nitrogen oxides, sulfur oxides, etc., contained in the atmosphere. The pollutant-containing atmosphere is contacted with an outer surface of a substrate, e.g., radiators, condensers, charge air coolers, transmission coolers, etc., which has been coated with an adsorptive material such as zeolites, molecular sieves, carbon, etc. The coated substrate is protected with an overcoat of at least one porous protective material such as alumina, silica and the like, such that the pollutants will come into contact with the adsorptive material, but harmful contaminants will be prevented from contacting the adsorptive material.

Abstract: The present invention relates to sulfur tolerant catalyst composites useful for reducing contaminants in exhaust gas streams, especially gaseous streams containing sulfur oxide contaminants. More specifically, the present invention is concerned with improved NOx trap catalysts for use in diesel engines as well as lean burn gasoline engines. The sulfur tolerant NOx trap catalyst composites comprise a platinum component, a support, and a NOx sorbent component prepared by hydrothermal synthesis. The NOx sorbent component comprises a first metal oxide and a second metal oxide. The metal in the first metal oxide is selected from the group consisting of aluminum, titanium, zirconium, silicon, and composites thereof, and the metal in the second metal oxide is selected from the group consisting of Group IIA metals, Group II metals, Group IV metals, rare earth metals, and transition metals. The metal in the first metal oxide is different from the metal in the second metal oxide.

Abstract: A method of treating exhaust from an internal combustion engine having an emission reduction device, such as a lean NOx trap. Exhaust from the engine is directed to a first sulfur trap, which treats the exhaust and discharges exhaust that is substantially free of sulfur. The exhaust from the first sulfur trap is normally directed to the emission reduction device, but is diverted to a second sulfur trap when the first sulfur trap is saturated. During this diversion, a reducing agent introduced upstream of the first sulfur trap aids in purging the first sulfur trap and in reducing metal sulfates and metal sulfites in the first sulfur trap to hydrogen sulfides, which are then treated by the second sulfur trap. When the first sulfur trap is thus purged, the exhaust gas is again directed to the emission reduction device.

Abstract: In general, the invention provides methods and associated apparatuses for removing odorant and sulfur compounds from a gas stream such as natural gas. As an example, such systems are typically required by fuel processor systems adapted to convert natural gas into reformate for use in fuel cell systems, where the odorant and sulfur compounds might otherwise poison the fuel processor and fuel cell catalysts Systems under the present invention are based on the use of at least two filtration stages such that the odorant removal function is segregated from the general removal of H2S.

Abstract: Carbon monoxide and carbonyl sulfide emissions are reduced in manufacturing processes, including titanium tetrachloride production processes. Gas is contacted with CO, COS, and an oxygen-containing gas with a suitable catalyst. The catalyst may be a metal oxide catalyst containing bismuth, cobalt and nickel, a xerogel or aerogel catalyst containing Au, Rh, Ru and Co in aluminum oxide/oxyhydroxide matrices, or a supported metal catalyst that contains at least one metal from the group Pd, Rh, Ru and Cu. In the latter case, the catalyst support is contains alumina or carbon. A catalyst composite of Au, Rh, Ru and Cr, and cerium oxide and lanthanum oxide may also be used.

Abstract: A method for desulfurizing gases is provided in which microdomains or microcrystals, of cerium oxide are provided within an alumina substrate. The cerium oxide microdomains within the alumina react within the sulfur in the gases to reduce the sulfur content of the effluent gas. The use of microdomains provides a high surface area of cerium oxide, and a stable surface area of the cerium oxide, which react in a rapid fashion with the sulfur-containing molecules leading to effective desulfurization to levels produced by thermodynamic calculations of the effluent gas.

Abstract: A method for utilizing ultra-thin catalytic monoliths, internal molding and high concentrations of reactive catalytic species to exploit the unique high surface area of Aerogels in order to achieve catalytic selectivity of the desired gas phase heterogeneous reaction.

Abstract: A process of regenerating a sulfided sorbent is provided. According to the process of the invention, a substantial portion of the energy necessary to initiate the regeneration reaction is provided by the combustion of a particulate metal sulfide additive. In using the particulate metal sulfide additive, the oxygen-containing gas used to regenerate the sulfided sorbent can be fed to the regeneration zone without heating or at a lower temperature than used in conventional processes wherein the regeneration reaction is initiated only by heating the oxygen-containing gas. The particulate metal sulfide additive is preferably an inexpensive mineral ore such as iron pyrite which does not adversely affect the regeneration or corresponding desulfurization reactions. The invention further includes a sorbent composition comprising the particulate metal sulfide additive in admixture with an active metal oxide sorbent capable of removing one or more sulfur compounds from a sulfur-containing gas stream.

Abstract: A highly efficient sulfide catalyst for reducing sulfur dioxide to elemental sulfur, which maximizes the selectivity of elemental sulfur over byproducts and has a high conversion efficiency. Various feed stream contaminants, such as water vapor are well tolerated. Additionally, hydrogen, carbon monoxide, or hydrogen sulfides can be employed as the reducing gases while maintaining high conversion efficiency. This allows a much wider range of uses and higher level of feed stream contaminants than prior art catalysts.

Abstract: The useful life of SOx additives having a SO2→SO3 oxidation catalyst component and a SO3 absorption component can be extended by employing each of these components as separate and distinct physical particles, pellets, etc.

Abstract: Carbonyl sulfide and/or hydrogen cyanide contained in a mixed gas are/is converted by contacting the mixed gas with an alkalized chromium oxide-aluminum oxide catalyst in the presence of steam, wherein the mixed gas and the steam at a volume ratio of 0.05≦steam/mixed gas≦0.3 are contacted with the alkalized chromium oxide-aluminum oxide catalyst at a gas hourly space velocity no less than 2000 h−1 at a temperature in the range of 150° C. through 250° C. In this case, the alkalized chromium oxide-aluminum oxide catalyst is set to have a grain size in the range of 1 mm through 4.5 mm. With this arrangement, since the surface area of a catalyst can be increased to a certain degree, the activity of the catalyst is increased to achieve the high processing speed, while since generation of a side reaction can be suppressed, lowering of the conversion rate of COS and/or HCN caused by the side reaction can be suppressed.

Abstract: In the oxide gas absorbing arrangement disclosed in the specification, metal foils having a thickness ≦0.05 mm are coated with an oxide gas absorbing layer containing gamma aluminum oxide. One metal foil is corrugated and joined to a smooth foil and the combined foils are rolled into a cylinder to provide parallel gas passages in which exhaust gases are exposed to the oxide gas absorbing layer. To enhance absorption turbulence is created in the gas passages by twisting the cylinder to narrow and contort the individual passages.