Abstract: A multiple cartridge fluid filter canister for mounting operatively in a standard filter housing includes spaced part upper and lower support plates that engage respective ends of a plurality of elongate filter cartridges that extend between the upper and lower support plates. The upper support plate carries an upper positioning element that depends from the upper support plate for engaging an upper end of a respective filter cartridge. The lower support plate carries a corresponding lower positioning element that extends upwardly from the lower support plate to engage a lower end of the filter cartridge. Annular seals surround the upper and lower positioning elements for respectively interengaging and sealing the upper and lower ends of the filter cartridge to restrict fluid flow between the cartridge and the upper and lower support plates. The upper and lower support plates define one or more inlets and outlets that communicate with corresponding fluid flow inlet and outlet lines in the filter housing.

Abstract: A filtering element for filtering devices, comprising a filtering material (5) which defines a filtering space and is intended for the filtration of fluids, and at least one water indicator (13, 19, 23) which is provided at a location coming into contact with fluid during the filtration mode and indicates the presence of water in the fluid in a visually recognizable manner, is characterized in that the at least one water indicator (13, 19, 23) is provided on an end cap (7, 9) for mounting at one end of the filtering material (5), and/or is at least partially part of the end cap (7, 9), and/or is provided on a fluid-permeable supporting structure (21) surrounding the filtering material (5), and/or is at least partially part of the supporting structure (21).

Abstract: A contamination indicator is for filter elements (12) for fluids that are replaceably housed in a filter housing (2). The indicator has a fluid-conveying connection (58) to the interior of the housing (2) and possesses an indicating device (52) providing information concerning the degree to which the filter element is contaminated (12). A temperature-dependently active actuation device (50) is connected upstream from the indicating device (52) in the direction of fluid inlet. By the actuation device, the indicating device (52) is activated when the fluid temperature has reached a predefinable threshold value.

Abstract: A filter element (10) of a filter for fluid and a method for producing a filter element (10) are described. The filter element (10) has a filter medium (14) which is designed as a hollow body (12) and is closed at the periphery, at least with respect to an element axis (16). The filter medium (14) is enclosed on at least part of its periphery and at least part of its axis by an electric heating jacket (26). The heating jacket (26) is arranged in or on a fluid-permeable supporting hollow body (24). The supporting hollow body (24) is open or can be opened, at least in an initial assembly of the filter element (10) on at least one peripheral side for arrangement on the filter medium hollow body (12).

Abstract: A filter is treated with a reduced amount of a halo active aromatic sulfanomide compound of Formula (I): wherein R1, R2, R3, R4, and R5 are independently selected from hydrogen, COOR?, CON(R?)2, alkoxy, CN, NO2, SO3R?, halogen, substituted or unsubstituted phenyl, sulfonamide, halosulfonamide, and substituted or unsubstituted C1-C12 alkyl; R? is hydrogen, an alkali metal, an alkaline earth metal, substituted C1-C12 alkyl, or unsubstituted C1-C12 alkyl; and R? is hydrogen or substituted or unsubstituted C1-C12 alkyl, where the two R? groups in CON(R?)2 may be independently selected; X is halogen; M is an alkali or alkaline earth metal; and n is the number of water molecules per molecule of the sulfonamide compound. The compound effectively suppresses odors pre-use, in use, and post-use for extended periods of time.

Abstract: An air filter housing includes an air inlet opening, an air outlet opening, and at least four filter bays each of which is configured to receive and hold a filter. The at least four filter bays form a V shape in the air filter housing and each side of the V shape includes at least two of the at least four filter bays. The air filter housing can be used in an air filtration system such as a residential HVAC system to achieve a MERV 16 filtration rating.

Abstract: The disclosure concerns air cleaners. Preferred air cleaners are shown which include a housing and a removable and replacement primary filter cartridge. Optional and advantageous features are shown. The preferred primary filter cartridge is conical in shape. A preferred optional safety or secondary filter cartridge is shown. Preferred methods of assembly and use are provided.

Abstract: A system is disclosed in which water-saturated desiccant in a dehydration unit, having previously been used to dehydrate natural gas, is regenerated in a closed loop process using liquid petroleum gas (LPG). LPG is pumped from a storage tank, vaporized and superheated. The superheated LPG gas enters the dehydration unit such that the hot gas passes over the desiccant thereby regenerating the desiccant. An overhead stream from the dehydration unit passes to a condenser where the temperature of the hot gas from the dehydration unit is dropped to form a fluid stream containing LPG, water and non-condensable gases. The fluid stream passes to a three phase separator for separating the fluid stream into a gas stream, a water stream, and a liquid stream containing LPG which is then returned to the storage tank for reuse in the closed loop process.

Abstract: Sorbent compositions, comprising a solid sorbent, a dispersive agent, and optionally a capture agent for enhanced wet-Flue Gas Desulfurization (wFGD) or wet scrubber unit function in a flue gas pollutant control stream is disclosed. The sorbent composition may include a sorbent with a dispersive agent, designed to enhance the dispersion of the sorbent in an aqueous sorption liquid of a wet scrubber unit, and therefore may be especially useful in EGU or industrial boiler flue gas streams that include one or more wet scrubber units. The sorbent composition may also include a capture agent useful in sequestering mercury and bromine, as well as other contaminants that may include arsenic, selenium and nitrates.

Abstract: Amines and amine derivatives that improve the buffering range, and/or reduce the chelation and other negative interactions of the buffer and the system to be buffered. The reaction of amines or polyamines with various molecules to form polyamines with differing pKa's extend the buffering range resulting in polyamines that have the same pKa yields a greater buffering capacity. Derivatives that result in zwitterionic buffers improve yield by allowing a greater range of stability.

Abstract: A fuel tank system is disclosed that includes a fuel tank and a first fluid flow path between a gas space in the fuel tank and outside of the fuel system. A gas separation membrane is disposed with a first side in communication with the first fluid flow path and a second side in communication with a second fluid flow path. A fluid control device is in communication with the second fluid flow path and is configured to provide fluid flow from the second fluid flow path to a liquid space in the fuel tank or to outside of the fuel system. A prime mover is disposed in communication with the second fluid flow path, and is configured to move fluid on the second fluid flow path from the second side of the separation membrane to the fuel tank liquid space or to outside of the fuel system.

Abstract: A method for continuously removing water vapor from a carrier gas is disclosed. This method includes, first, causing direct contact of the carrier gas with a liquid mixture in a separation chamber, the carrier gas condensing at a lower temperature than the water vapor. A combination of chemical effects cause the water vapor to condense, complex, or both condense and complex with the liquid mixture.

Abstract: A sorbent composition for removing mercury from flue gas, including a powdered sorbent having a fifty percent distribution particle size of from about 20 micrometers to about 75 micrometers. The invention also include a method of cleaning flue gas, the method including injecting a powdered sorbent into the flue gas, wherein the powdered sorbent has a fifty percent distribution particle size of from about 20 micrometers to about 75 micrometers.

Abstract: A method for reducing pollution in a cement kiln environment and a system for treating cement kiln exhaust gas are provided. The method includes the steps of: treating a cement kiln exhaust gas stream with a treating fluid, such as a water soluble alkaline-earth metal sulfide. In one application, the treating fluid is injected by spraying droplets into the cement kiln exhaust gas stream. A system for treating cement kiln exhaust gas includes a reagent containing a water soluble alkaline-earth metal sulfide in water, and a nozzle to spray the reagent into the cement kiln exhaust gas stream.

Abstract: A fluid conditioning unit is provided that includes a housing, a cap, a cartridge device, and a filter cartridge. The cap is threadably secured to and unsecured from the housing by rotation about an axis of the housing. The cap forms a removable seal with the housing when secured thereto. The cartridge device is secured to the cap in a manner that restricts movement of the cartridge device with respect to the cap along the axis but allows rotation of the cartridge device with respect to the cap about the axis. The filter cartridge is removably secured to the cartridge device and is disposed in the housing along the axis.

Abstract: The invention provides cleaning agents, cleaning liquids and cleaning methods that effectively remove contaminants which are impossible to remove sufficiently with conventional cleaning liquids at the occurrence of a decrease in performances such as permeation flux and salt rejection rate due to contamination of permeable membranes, in particular aromatic polyamide RO membranes used in water treatment. Permeable membranes are cleaned with a cleaning liquid which is an aqueous solution including a chloramine compound and an alkali agent and having a pH of 10 or above. The chloramine compound is preferably one obtained by mixing a compound having a primary amino group with hypochlorous acid and/or a hypochlorite.

Abstract: The disclosure relates to a system and method for cleaning filters, such as membrane filters. More particularly, a method and system are disclosed for retaining a plurality of small particulates, preferably in the shape of beads, which contact sludge or other despots on the membrane filters to remove unwanted debris that would otherwise form on the cleaning filters. In various embodiments, the plurality of small particulates are retained in a permeable enclosure formed of wedgewire.

Abstract: The method of verifying an RO membrane of an RO installation is characterized in that the conductivity values of the supplied raw water and of the permeate and the amount of the raw water inflow and the concentrate outflow are continuously or cyclically measured and that the efficiency of the RO membrane, its retention rate and/or filtration efficiency are calculated from the measured values.

Abstract: Disclosed herein are surface-modified membranes and other surface-modified substrates exhibiting switchable oleophobicity and oleophilicity in aqueous media. These membranes and substrates may be used for variety of applications, including controllable oil/water separation processes, oil spill cleanup, and oil/water purification. Also provided are the making and processing of such surface-modified membranes and other surface-modified substrates.

Abstract: A porous membrane is made from a poly(phenylene ether) copolymer containing 10 to 40 mole percent repeat units derived from 2-methyl-6-phenylphenol and 60 to 90 mole percent repeat units derived from 2,6-dimethylphenol; and a block copolymer containing backbone or pendant blocks of poly(C2-4 alkylene oxide). The porous membrane is made by dissolving the poly(phenylene ether) copolymer in a water-miscible polar aprotic solvent to form a membrane-forming composition; and phase-inverting the membrane forming-composition in a first non-solvent composition to form the porous membrane. A method of making a hollow fiber by coextrusion through a spinneret having an annulus and a bore, includes coextruding the membrane-forming composition through the annulus, and a first non-solvent composition through the bore, into a second non-solvent composition to form the hollow fiber.

Abstract: A carbonation machine includes a pneumatic chamber with a movable wall. The wall moves outward to depress a pin of a gas release valve of a gas canister that is held in a canister holder of the machine when air pressure in the chamber is increased. An air release valve is closable to retain air in the chamber. An air pump is operable to pump air from the ambient atmosphere into the chamber so as to increase air pressure in the chamber. A controller is configured to close the air release valve and to operate the air pump to increase the air pressure in the chamber to move the movable wall outward to open the gas release valve of the canister to cause release of gas from the canister to carbonate a liquid, and to open the air release valve to enable the gas release valve to close.

Abstract: A polymeric invert emulsifier is provided which is particularly suitable for use in demanding environments.

Abstract: An intermediate medium heat exchanging device for a supercritical water oxidation system includes a material main loop, an intermediate medium loop and a replenishment branch. A material pump, a preheater, a spray desuperheater, a reactor and a regenerator are connected in sequence to form the material main loop; a buffer tank, a circulating pump, the regenerator, the preheater and a water cooler form the intermediate medium loop. A back pressure valve is located above the buffer tank. The replenishment branch includes a cooling water pump, an outlet of the cooling water pump is divided into two sub-branches, one sub-branch is connected with the spray desuperheater, and another sub-branch is connected with the buffer tank. The intermediate medium heat exchanging device is reasonable in structural design, and is able to maximumlly reduce the investment cost and ensure the stable operation of the system.

Abstract: A reaction-regeneration device for catalytic dehydrogenation or/and catalytic cracking of alkanes comprises a reaction device and a regeneration device. The reaction device comprises a reactor and a disengager, and the disengager is located at an upper part of the reactor. The reactor comprises a tapering section, and diameters of cross sections of the tapering section gradually decrease from bottom to top. Secondary conversion of alkenes caused by back-mixing is reduced, and thus the yield and selectivity to alkenes are increased.

Abstract: The invention relates to a method for reducing the viscosity of a nanofibrillar cellulose hydrogel, wherein the method comprises mixing a nanofibrillar cellulose hydrogel with an aqueous growth medium for cell culture, wherein the aqueous growth medium contains one or more salts and optionally one or more sugars, using shearing forces so that a homogeneous dispersion is formed. The invention further relates to a dispersion comprising a nanofibrillar cellulose hydrogel and an aqueous growth medium for cell culture and to a use of an aqueous growth medium.

Abstract: The application describes a process for the preparation of microcapsules, wherein the microcapsules have a volume average diameter d of 15 to 90 ??? and a percentage of the shell weight of 3 to 40%, with reference to the total weight of capsules, wherein the shell of the microcapsules comprises at least one polyurea and the core comprises at least one lipophilic component, comprising the step of adding hydroxyalkylcellulose to a dispersion of polyurea microcapsules, microcapsules and their uses.

Abstract: The present disclosure provides methods, device, and system for wafer processing. The wafer processing apparatus uses lid dispenser to disperse at least one reagent to the surface of the wafer. Further, the wafer is positioned on top of a rotatable vacuum chuck configured to spread at least one reagent over the surface of the wafer via a centrifugal force or surface tension, thereby permitting the at least one reagent to react with an additional reagent. Further, when dispensing the at least one reagent, a separation gap between the lid dispenser and the wafer is at a predetermined distance, for example, from 50 ?m to 2 mm.

Abstract: Systems, devices, and methods for providing a magnetic coil assembly wired in series or parallel at low or high voltage provided from a direct current source or an alternating current source that can produce a concentrated magnetic energy at the central core of the magnetic coil to energize a tubular reactor passing through the coil assembly core. The magnetic energy can be transferred outside of the coil assembly core by a magnetic transfer probe to energize a magnetic chemical reactor vessel.

Abstract: A method for processing hydrogen chloride from isocyanate preparation comprises the steps: a) providing hydrogen chloride; b) purifying the hydrogen chloride provided; and furthermore step c) or step d): c) bringing the purified hydrogen chloride into contact with water and/or with hydrochloric acid which is not saturated with respect to uptake of hydrogen chloride, d) further processing the purified hydrogen chloride to chlorine by partial oxidation. The hydrogen chloride provided in step a) contains organic and/or nitrogen-containing impurities and in step b) the purification is carried out by bringing hydrogen chloride into contact with hydrochloric acid which is saturated to the extent of ?90% with respect to uptake of hydrogen chloride at least in a first gas scrubber (10) and circulating this hydrochloric acid at least partially through the first gas scrubber (10).

Abstract: A sorbent composition with improved acid gas reactivity comprising calcium hydroxide particles is provided. In the calcium hydroxide composition, about 90% percent of the calcium hydroxide particles are less than or equal to about 10 microns; the ratio of 90% of the calcium hydroxide particles below a specified size to the ratio of 10% of the calcium hydroxide particles above a specified size is less than about 8; and the calcium hydroxide particles have a BET surface area of about 18 m2/g or greater.

Abstract: Carbide-derived carbons are provided that have high dynamic loading capacity for high vapor pressure gasses such as H2S, SO2, or NH3. The carbide-derived carbons can have a plurality of metal chloride or metallic nanoparticles entrapped therein. Carbide-derived carbons are provided by extracting a metal from a metal carbide by chlorination of the metal carbide to produce a porous carbon framework having residual metal chloride nanoparticles incorporated therein, and annealing the porous carbon framework with H2 to remove residual chloride by reducing the metal chloride nanoparticles to produce the metallic nanoparticles entrapped within the porous carbon framework. The metals can include Fe, Co, Mo, or a combination thereof. The carbide-derived carbons are provided with an ammonia dynamic loading capacity of 6.9 mmol g?1 to 10 mmol g?1 at a relative humidity of 0% RH to 75% RH.

Abstract: Coordination polymers of MOF type, comprising a repeating unit of the general formula [M2(dcx)2L2], wherein M represents a metal cation (M2+), dcx represents an anion of a dicarboxylic acid and L represents a neutral molecule of hydrazone. A method for preparation of coordination polymers of MOF type, wherein in the first step a compound of aldehyde or ketone group is condensed with a hydrazide, and in the second step the condensation product is reacted using a metal compound and a dicarboxylic acid. An application of coordination polymers of MOF type for the detection, capturing, separation, or storage of molecules, for the fabrication of ionic conductors, for the construction of batteries and fuel cells, as well as drug carriers.

Abstract: Disclosed is an attrition-resistant superabsorbent polymer, including a superabsorbent polymer, porous superhydrophobic microparticles, and water, thus increasing moisture content of the superabsorbent polymer and a method of manufacturing the attrition-resistant superabsorbent polymer is also provided.

Abstract: The present invention relates to a fast particulate superabsorbent polymer composition comprising a polymer comprising a neutralized aluminum salt solution applied to the surface of a particulate superabsorbent polymer; wherein an aqueous solution of the neutralized aluminum salt has a pH value from about 5.5 to about 8; and subsequent to subjecting the particulate superabsorbent polymer composition to the Processing Test, the particulate superabsorbent polymer composition has a permeability stability index of from about 0.60 to about 0.99, and a compressibility from 1.30 mm2/N to about 4 mm2/N as measured by the Compression Test, and wherein the particulate superabsorbent polymer composition may have a Vortex time of from 25 to 60 seconds and absorbency under load at 0.9 psi of from 15 to 21 g/g.

Abstract: The present disclosure relates to a material preferably used in a guard bed, and having an increased capacity to adsorb catalyst poisons, as measured by collidine update at 200° C. The material is made by a method in which it is treated by being dried with a drying gas, preferably, at a temperature greater than about 200° C. The treated material may be used to remove impurities from untreated feed streams to, for example, aromatic alkylation and transalkylation processes, where such impurities act as catalyst poisons that cause deactivation of the acidic molecular sieve-based catalysts used, thereby increasing the cycle length of such catalysts.

Abstract: An efficient and economical process for H2 evolution by water splitting, catalyzed by layered oxides that function in UV and visible light.

Abstract: The present invention relates to an anti-coking catalyst having a physical property of reducing coke formation, which comprises a solid acid catalyst containing gadolinium (Gd) on the surface, a preparation method thereof, and a use thereof. The preparation method includes a first step of determining the amount of gadolinium (Gd) or a Gd-providing precursor to be used relative to the total weight of the solid acid catalyst, which reducing the coking of a specific solid acid catalyst below a specific level under a specific reaction condition; and a second step of preparing a Gd-containing solid acid catalyst using the amount determined in the first step. The catalyst according to the present invention is a catalyst in which an appropriate weight ratio of gadolinium is supported on the surface of a pure solid acid substance or solid acid substance on which a specific metal is supported.

Abstract: An exhaust gas purification catalyst, excellent in the NOx purification capacity and the HC purification capacity, includes a substrate and a catalyst coating layer formed on the surface of the substrate, wherein the catalyst coating layer comprises the upper and lower layer including a lower layer being closer to the surface of the substrate and an upper layer being relatively remote from the surface of the substrate. The upper layer of the catalyst coating layer includes Rh, Pd, and a carrier. The lower layer of the catalyst coating layer includes at least one noble metal selected from Pd and Pt and a carrier. 65% by mass or more of Pd in the upper layer exists in a layer up to 50% of the upper layer in a thickness direction from the surface of the upper layer being relatively remote from the surface of the substrate. The ratio of Pd to Rh by mass (Pd/Rh) is 0.5 to 7.0 in the upper layer.

Abstract: Disclosed are a complex oxide catalyst for dehydrogenation, a method of preparing the same, and use thereof, wherein the catalyst includes a first transition metal selected from the group consisting of gallium, vanadium, chromium, manganese, molybdenum, and zinc, a hydrogen-activating metal including at least one selected from the group consisting of Groups 8, 9, 10, and 11 elements in a periodic table, and alumina, the amount of the first transition metal being 0.1 wt % to 20 wt %, the amount of the hydrogen-activating metal being 0.01 wt % to 2 wt %, based on the amount of the alumina, the first transition metal being loaded on the alumina, and the hydrogen-activating metal being surrounded by the alumina.

Abstract: A supported catalyst having a calcined, predominantly aluminum, oxide support and an active phase of 5 to 65% by weight nickel with respect to the total mass of the catalyst, said active phase having no group VIB metal, the nickel particles having a diameter less than or equal to 20 nm, said catalyst having a mesopore median diameter greater than or equal to 14 nm, a mesopore volume measured by mercury porosimetry greater than or equal to 0.45 mL/g, a total pore volume measured by mercury porosimetry greater than or equal to 0.45 mL/g, a macropore volume less than 5% of the total pore volume, said catalyst being in the form of grains having an average diameter comprised between 0.5 and 10 mm. The invention also relates to the process for the preparation of said catalyst and the use thereof in a hydrogenation process.

Abstract: The present invention is to provide a catalyst for hydrocracking that is capable of decreasing the content of oxygen components contained in hydrocarbons synthesized from a vegetable fat or oil, an animal fat or oil, and/or a coal liquefaction oil each containing at least one selected from a fatty acid, a fatty acid ester, and an alkylphenol compound, and a hydrocarbon production method using the same. The catalyst for hydrocracking of the present invention contains a carrier containing a porous oxide, and nickel and molybdenum supported on the carrier, the catalyst for hydrocracking being subjected to a hydrogen reduction treatment, and having a mass ratio (X/(X+Y)) of a nickel content (X) in terms of nickel oxide (NiO) to the sum of the nickel content (X) in terms of nickel oxide (NiO) and a molybdenum content (Y) in terms of molybdenum oxide (MoO3) of 0.5 or more and 0.9 or less.

Abstract: Methods for regenerating a spent catalyst are disclosed. Such methods may employ a step of chlorinating the spent catalyst in the gas phase, followed by decoking the chlorinated spent catalyst, and then fluorinating the de-coked catalyst in a fluorine-containing solution of a fluorine-containing compound.

Abstract: The invention relates to shaped catalyst bodies for the oxidation of SO2 to SO3, which comprise vanadium, at least one alkali metal and sulfate on a silicon dioxide support material, wherein the shaped body has the shape of a cylinder having 3 or 4 hollow-cylindrical convexities, obtainable by extrusion of a catalyst precursor composition comprising vanadium, at least one alkali metal and sulfate on a silicon dioxide support material through the opening of an extrusion tool, wherein the opening of the extrusion tool has a cross section formed by 3 or 4 partly overlapping rings whose midpoints lie essentially on a circular line having a diameter of y, wherein the rings are bounded by an outer line lying on a circle having an external diameter x1 and an inner line lying on a circle having an internal diameter x2.

Abstract: A beta zeolite catalyst for the preparation of a BTEX (benzene, toluene, ethylbenzene, xylene) mixture from polyaromatic hydrocarbons and a preparation method of the same are disclosed. The beta zeolite catalyst demonstrates high conversion of polyaromatic hydrocarbons and high BTEX production yield by containing optimum contents of the group VIB metals and cocatalysts, so that it can be effectively used as a beta zeolite catalyst for the production of BTEX.

Abstract: The honeycomb structure includes a honeycomb structure body made of a zeolite material containing at least a coarse particle zeolite having a large average particle diameter (coarse zeolite particles). A fine particle zeolite having an average particle diameter smaller than that of the coarse particle zeolite (fine zeolite particles), and an inorganic bonding material, the coarse particle zeolite (the coarse zeolite particles) is a chabazite type zeolite in which an average particle diameter of primary particles is 2 ?m or more and 6 ?m or less, and in the fine particle zeolite (the fine zeolite particles), an average particle diameter of primary particles is 0.02 ?m or more and smaller than 2 ?m, and in the zeolite material which is comprised the honeycomb structure body, a ratio of a volume of pores having pore diameters of 0.02 to 0.15 ?m to a volume of all pores is 42% or less.

Abstract: Catalysts for the dehydration of lactic acid, lactic acid derivatives, or mixtures thereof to acrylic acid, acrylic acid derivatives, or mixtures thereof in liquid phase comprising an ionic liquid (IL) and an acid are provided.

Abstract: Catalysts for the dehydration of lactic acid, lactic acid derivatives, or mixtures thereof to acrylic acid, acrylic acid derivatives, or mixtures thereof in liquid phase comprising an ionic liquid (IL) and an acid are provided.

Abstract: A palladium hydride nanomaterial includes nanostructures having a chemical composition represented by the formula: My-PdxHz, where M is at least one metal different from palladium; x has a non-zero value in the range of 0 to 5; y has a value in the range of 0 to 5; and z has a non-zero value in the range of 0 to 5.

Abstract: A novel metal organic framework, EMM-42, is described having the structure of UiO-66 and comprising bisphosphonate linking ligands. EMM-42 has acid activity and is useful as a catalyst in olefin isomerization. Also disclosed is a process of making metal organic frameworks, such as EMM-42, by heterogeneous ligand exchange, in which linking ligands having a first bonding functionality in a host metal organic framework are exchanged with linking ligands having a second different bonding functionality in the framework.

Abstract: A highly pure optically active proton pump inhibitor compound can be produced safely and inexpensively in a high yield and enantioselectivity by a method of producing an optically active sulfoxide of Formula 2 or a salt thereof, comprising oxidizing a sulfide of Formula 1 or a salt thereof with hydrogen peroxide using an iron salt in the presence of a chiral ligand of Formula 3; wherein A is CH or N; R1 is hydrogen atom, an alkyl optionally substituted by halogen(s), or an alkoxy optionally substituted by halogen(s); one to three R2 may exist, and each of R2 is independently an alkyl, a dialkylamino, or an alkoxy optionally substituted by halogen(s) or alkoxy(s); each of R3 is independently hydrogen atom, a halogen, cyano or the like; R4 is a tertiary alkyl; and * and ** represent respectively R configuration or S configuration.