Abstract: An oxygen scavenger characterized in that the effective component thereof consists of a heterocyclic compound with N--N bond in a ring thereof An oxygen scavenger characterized in that the effective component thereof consists of a heterocyclic compound with N-substituted amino group. An oxygen scavenger characterized in that the effective component thereof consists of a heterocyclic compound represented by the following formula: ##STR1## (wherein a, b are integers between 0 and 5 to satisfy a relation "2.ltoreq.a+b.ltoreq.5"). ##STR2## An oxygen scavenger characterized in that the effective component thereof consists of azodicarbonamide. An oxygen scavenger characterized by including a heterocyclic compound with N-substituted amino group, or the salt thereof, and a hydroxybenzene derivative. Those may contain further neutral amine, alkalic agent and/or water soluble polymer.

Abstract: A method and an apparatus for controlling reactions of a gas and a fluid that makes use of excellent reactivity of carbon soot molecules, metal porphyrin complexes and metal phthalocyanin complexes which are in an excited state has an arrangement that the carbon soot molecules, the metal porphyrin complexes and the metal phthalocyanin complexes which are excited by a physico-chemical method, such as light irradiation, and a gas containing oxygen are brought into contact with each other to generate active oxygen. Further, the gas containing the harmful substance and a fluid are brought into contact with each other so that direct reactions of the active oxygen and the excited molecules decompose the harmful substances.

Abstract: A method for the in-situ remediation of contaminants including soluble metals more noble than iron and halogenated hydrocarbons that are present in groundwater, absorbed to soil, and exist in the free product state in a soil volume. An inert pressurized gas in combination with an atomized iron powder-water slurry is used to inject pre-determined quantities of reactive zero valent iron powder relative to the quantity of contaminants present in the soil for obtaining preselected rates of remediation with minimum quantities of iron powder and with reaction products within a preferred acidic pH range. Features, such as particle surface area and carbon content, are identified that enhance the reactivity of the iron powder.

Abstract: Waste water containing ammonium nitrogen is brought into contact with either one of a catalytically acting substance for converting an ammonium oxidizing product produced by being oxidized by oxidizing bacteria for oxidizing ammonium nitrogen or converting bacteria for reproducing converting capacity of the catalytically acting substance in the aerobic condition.

Abstract: A composition for reducing the concentration of molecular oxygen present in an atmosphere or liquid, comprising at least one reducible organic compound which is reduced under predetermined conditions. The reduced form of the compound being oxidizable by molecular oxygen, wherein the reduction and/or subsequent oxidation of the organic compound occurs independent of the presence of a transition metal catalyst.

Abstract: The concentration of potentially toxic hexavalent chromium, {Cr(VI)}, in chromium-bearing soils/materials existing in the form of soils, sludges, sediments, fill, industrial wastes, or other materials is decreased by applying and mixing a single reducing agent, ascorbic acid, to effect chemical reduction of Cr(VI) to a less toxic valence state. Ascorbic acid is added at ambient temperature in aqueous solution or slurry form and mixed with Cr(VI)-bearing soils/materials in amounts based on test results of representative samples of the material to be treated. Ascorbic acid may also be added in a dry form if sufficient moisture is present in the soils/materials to allow for dissolution of the ascorbic acid and reaction with the Cr(VI) in the material. The percentage reduction of the Cr(VI) concentration is greater and is achieved more rapidly than previously reported using other organic chemical reducing agents.

Abstract: A fluid treating method for treating fluid to reduce the concentration of undesirable nitrogen compounds and/or metal constituents contained therein is disclosed. The method utilizes a bed of metal particulate matter. The metal particulate matter comprises copper. Preferably, the metal particulate also contains zinc and can be in the form of an alloy. The fluid treated is often water, preferably, drinking water. Among the nitrogen compounds that may be effected by the present method are inorganic nitrates and nitrites and/or metals may be aluminum, arsenic, barium, cadmium, chromium, copper, gold, iron, lead, mercury, selenium and silver.

Abstract: A method of treating paint sludge containing uncured polymer resin, water and/or solvent is provided in which a paint sludge putty is formed which may be used as a replacement for polymeric components used to form compounded polymeric compositions. The treated paint sludge putty or powder comprises from about 5 to 90% by weight of the total compounded polymeric composition and may be used in a variety of compositions including pressure sensitive sealants, caulking sealants, automotive sealants, polyvinyl chloride plastics, rubbers and asphalt cement coatings, and waterbased sealers and coatings.

Abstract: A method for removing dissolved oxygen from alkaline water containing dissolved oxygen at a temperature greater than 250.degree. F. which comprises the step of: adding to said alkaline water containing dissolved oxygen an effective oxygen-scavenging amount of a water-soluble semicarbazide of the formula ##STR1## wherein R.sub.1 and R.sub.2 are selected from the group consisting of C.sub.1 -C.sub.10 alkyl, cycloalkyl, aryl, cycloalkyloxy and alkyloxy groups.Preferred materials are 4-phenyl semicarbazide, 4-isopropyl semicarbazide, 4-4-diethyl semicarbazide and carbazoyl morpholine. Below 400.degree. F., a catalyst is also required.

Abstract: This is a method of treatment of materials with the use of a sacrificial metal and reducible ions which comprises steps ofa) contacting the material to be treated with the surface of the said sacrificial metal, wherein the said material to be treated is included in an aqueous solution or emulsion or suspension; andb) inducing treatment processes at the surface of the said sacrificial metal by providing said reducible ions included in an electrolyte, wherein the said reducible ions react with the said sacrificial metal to form oxidation-reduction products comprising dissolved or suspended reduced species and dissolved or suspended species from oxidizing the said sacrificial metal.The method can be used for treatment of water, groundwater, including in-situ, wastewater, polluted gases, solid waste, and other materials.

Abstract: A cooling tower water treatment system removes contaminants include chlorine, calcium carbonate as calcite, and microorganisms from water in the system with redox media in a fluidized bed. The treatment system includes a treatment bed, in the form of a column, having a reaction chamber of a first diameter and a retention chamber of a second diameter, the second diameter being greater than the first diameter. Redox media, in the reaction chamber, is fluidized by water flowing in a direction countercurrent to gravity and is held in place, without the use of screens or filters, by a reduction in flow rate of the fluidizing media resulting from the larger diameter of the retention chamber. Preferably, the treatment system includes a physical filtration unit, such as an automatic backwashing sand filter, to prevent entry of particulates and scale into the reaction chamber.

Abstract: To decrease the nitrate content of water, it is proposed to reduce nitrate to nitrogen in two stages. The first of these stages is a photochemical reduction to nitrite, and the second stage is a reduction of nitrite to nitrogen using amidosulphuric acid.

Abstract: Treatment of halogenated hydrocarbon contaminants in groundwater is accomplished by passing the water through a bed of granular iron (43). An electrical circuit (47) is promoted for providing electrons for reducing the contaminant. The circuit may be made using a DC supply, by configuring an electrolytic circuit, or by providing a layer of a second metal such as zinc placed next to the iron bed, thereby creating a galvenic circuit.

Abstract: A water denitrification process is provided which comprises stopping the reduction of nitrate at nitrite, lowering the pH of the water, and then gas stripping the nitrite out of the water by using air as the gas in a sparger. This allows considerable savings to be realized based on the reduced chemical removal costs as compared to other water denitrification processes.

Abstract: According to the present invention, there is provided a method for nonbiologically treating an chlorinated organic compound contained in an environment polluted with the chlorinated organic compound, which comprises the step of introducing silicon into the environment to dechlorinate the chlorinated organic compound.

Abstract: A cooling tower water treatment system removes contaminants include chlorine, calcium carbonate as calcite, and microorganisms from water in the system with redox media in a fluidized bed. The treatment system includes a treatment bed, in the form of a column, having a reaction chamber of a first diameter and a retention chamber of a second diameter, the second diameter being greater than the first diameter. Redox media, in the reaction chamber, is fluidized by water flowing in a direction countercurrent to gravity and is held in place, without the use of screens or filters, by a reduction in flow rate of the fluidizing media resulting from the larger diameter of the retention chamber. Preferably, the treatment system includes a physical filtration unit, such as an automatic backwashing sand filter, to prevent entry of particulates and scale into the reaction chamber.

Abstract: A process for treating waste water of flue gas desulfurization comprising successively adjusting the pH of the waste water to 5 or less, bringing the waste water into contact with a column packed with fine particles of iron, flocculating the waste water, removing formed flocs from the waste water by solid-liquid separation, and optionally, bringing the remaining waste water into contact with a resin for COD adsorption, successively. Hazardous substances, such as oxidative substances, peroxosulfuric acid, iodic acid, heavy metals such as copper and lead, and non-metallic substances such as selenium compounds and fluorites, can be removed simultaneously and efficiently from the waste water of flue gas desulfurization containing these hazardous substances by using the process which is a simplified waste water disposal system.

Abstract: The present invention provides a method for rejuvenating an aqueous alkanolamine solution being at least partially deactivated from contact with an acid gas, said rejuvenation method comprising contacting said aqueous alkanolamine solution with hydrogen in the presence of a hydrotreating catalyst under hydrotreating conversion conditions including contact time sufficient to increase the acid gas sorption capacity of said aqueous alkanolamine solution.

Abstract: A method for improving water quality including the steps of providing a supply of water to be treated and decreasing the redox potential of the water principally by supplying thereto atomic hydrogen.

Abstract: The invention concerns a method of removing substances present in water, in particular halogen-oxygen compounds which remain in the water as residues of disinfecting or are formed as by-products of oxidative water treatment. According to the invention, the substances present in water are removed by catalytic reduction in the presence of hydrogen on a supported precious metal catalyst.

Abstract: A process is provided for treating aqueous streams contaminated with electron affinic contaminants. Accordingly, these contaminants are removed by producing a reactive intermediate that is generated in-situ and then reacting the reactive intermediate thus produced with the electron affinic contaminant. The reactive intermediate is produced in the aqueous stream by maintaining low levels of oxygen in the stream and by providing a reducing radical precursor, such as an alcohol, to the aqueous stream.

Abstract: The invention relates to a process for eliminating adsorbable organic halogen compounds from an aqueous phase, in particular from wastewater or from a process solution, in which the aqueous phase is treated with a nonaqueous extraction medium in a liquid-liquid extraction, which comprises, after the extraction, subjecting the adsorbable organic halogen compounds in the extraction medium to a Wurtz-Fittig reaction. Only small amounts of noncritical products such as NaOH and Hcl, which can be readily removed, are formed in the nonaqueous extraction medium. By means of this process, the cost of the chemicals which conventionally arises in the elimination of the adsorbable organic halogen compounds is considerably decreased.

Abstract: Addition of ferrous ions to clay and ferric minerals in the ground creates in situ reactive zones which dehalogenate halogenated contaminants in ground water flowing through the reactive zone.

Abstract: The invention is a method for removing dissolved oxygen from alkaline water which comprises adding to alkaline water containing dissolved oxygen an effective oxygen-scavenging amount of a water-soluble carboxylate at temperatures above 400.degree. F. A preferred material is tartronic acid. At lower temperatures, a catalyst is also required.

Abstract: A method of treating fluid to reduce the concentration of undesirable materials such as metals, halogens and bacteria through the use of alloys of three or more inorganic elements which will give rise to three or more different redox potentials so as to cause simultaneously the removal of plural contaminants in a single operation.

Abstract: Selenate ion is removed from a selenate ion-containing aqueous waste liquid by treating the aqueous liquid with an organic reducing agent in the presence of a photocatalyst while irradiating the aqueous waste liquid with an actinic radiation to convert the selenate ion into elemental selenium which is in the form of solid precipitates and/or hydrogen selenide which is in the form of a gas.

Abstract: Sea water previously filtered and temperature controlled, and which includes added hydrogen is continuously pumped at a constant rate to a deoxygenation reactor containing a divided platinum catalyst on a granular activated carbon support. The deoxygenated sea water is continuously discharged from the reactor through a line. The divided platinum of the catalyst is present in a superficial layer of the support grains and the platinum dispersion in the catalyst grains is at least 10%.

Abstract: A process for regenerating a supported noble metal catalyst and also a process for catalytic treatment of wastewater containing, in particular, organohalogen contaminants, in which the process for regenerating the catalyst is a part of the overall wastewater treatment process.

Abstract: A method for stabilizing an aqueous solution containing sulfite or bisulfite ions and a water-soluble metal catalyst. The method comprises incorporating a stabilizing amount of a alpha substituted carboxylic acid or salt thereof or a vinyl carboxylic acid or salt thereof in the solution. The carboxylic acid inhibits sludge formation when the aqueous solution is stored. The preferred carboxylic acid, citric acid, also enhances the oxygen scavenging rate of the sulfite and bisulfite when the solution is used to treat aqueous systems for oxygen removal.

Abstract: In a catalytic treatment process for effluents containing organic and inorganic compounds, a noble metal catalyst on a support is used. The support preferably is produced according to the sol-gel process.

Abstract: In a process for the catalytic treatment of aqueous liquids containing germs, for example, for the catalytic removal of oxygen, nitrite or nitrate in drinking, culinary or waste water, the germ contamination of a catalysts which are used can be prevented when the process is carried out in the fluidized bed.

Abstract: The invention is a method for removing dissolved oxygen from alkaline water which comprises adding to alkaline water containing dissolved oxygen an effective oxygen-scavenging amount of a water-soluble sulfoxylate. A preferred material is sodium formaldehyde sulfoxylate.

Abstract: A method for dehalogenating contaminated ground water and/or soil where the contaminated area is contacted with a titanium carboxylic acid derivative such as titanium oxalate, titanium citrate or titanium nitriloacetate and a corrin or porphyrin catalyst preferably vitamin B12 compound. The result of contact with the contaminated source is that the compounds reductively dehalogenate the contaminates thereby making it less toxic. This is achieved by making use of the non-toxic reagents, namely the corrin or porphyrin catalyst such as vitamin B12 and the titanium carboxylic acid derivative.

Abstract: A process for reducing the amount of halogenated organic materials in aqueous systems by hydrogenating the halogenated organic materials in the aqueous system in the presence of ions of a metal from the 8th secondary group of the periodic system of elements at a pH of from 7 to 14 and a temperature of from 20.degree. C. to 140.degree. C.

Abstract: A method of detoxifying biocide which is toxic to aquatic life comprising contacting said biocide with a water soluble organic thiol compound. Applications of the method are primarily for biocide spills or for industrial effluents which comprise biocide and must be detoxified prior to release into the environment, and must pass a photoluminescent bacterial assay. Kits are also disclosed.

Abstract: The present invention relates to various methods, such as an above-ground method and an in-ground method, of using a palladized iron bimetallic system for the dechlorination of chlorinated organic compounds from various effluents or contaminated soil containing the same. The use of palladized iron bimetallic system results in the dechlorination of the chlorinated organic compound into environmentally safe reaction products.

Abstract: The present invention relates to various methods, such as an above-ground method and an in-ground method, of using a palladized iron bimetallic system for the dechlorination of chlorinated organic compounds from effluents containing the same. The use of palladized iron bimetallic system results in the dechlorination of the chlorinated organic compound into environmentally safe reaction products. The present invention also provides kits, devices, and other instruments that use the above-mentioned palladized iron bimetallic system for the dechlorination of chlorinated organic compounds.

Abstract: Disclosed herein is a process for removing acrolein from a gaseous or liquid mixture, in one case aqueous solutions, involving contacting the mixture with a compound selected from the group consisting of sodium hypochlorite; an acid salt of hydroxylamine; a urea compound such as urea itself or thiourea; sodium bisulfite and 4,4-dimethyl-1-oxa-3-azacyclopentane in an amount effective to substantially remove acrolein has been discovered. The process works particularly well in selectively scavenging acrolein from aqueous solutions containing acrylonitrile.

Abstract: Chemical-free autodecomposition of chlorine species to chloride ion and oxygen gas by contacting a chlorine containing liquid solution with a decomposition catalyst consisting of transition metals and their compounds in association with a high surface area per mass. The catalyst comprises Raney metals selected from the group including Raney Cu, Raney Ni, and Raney Co, and aluminum doped with transition metals selected from the group including vanadium, chromium, manganese, iron, cobalt, nickel, copper and zinc.

Abstract: The present invention provides a method for stimulating in-situ microbial biodegradation of halogenated organic compounds in an aqueous subsurface environment comprising the delivery of hydrogen, in the absence of nutritional factors, into the subsurface environment.

Abstract: Iron and ferrous sulfide in specific amounts are combined under aerobic or anaerobic conditions to reduce halogenated hydrocarbons in aqueous compositions to non-toxic by-products at near neutral pH and Eh values below -325 mV. The combination of iron metal and ferrous sulfide in relative amounts gives the unexpected result of a faster reduction rate using iron or ferrous sulfide alone and a controlled pH.

Abstract: A method for significantly improving the dechlorination of chlorinated hydrocarbon compounds is disclosed. The method involves admixing preformed ferrous citrate with chlorinated hydrocarbon contaminated aqueous compositions both in situ and ex situ. The use of ferrous citrate decreases the oxidation potential of the Fe.sup.+2 /Fe.sup.+3 redox couple to cause oxidation by the chlorinated hydrocarbon with its concomitant reduction, thereby generating chloride ion.

Abstract: Process for the decontamination of decontaminants in waste waters, wherein the waste water stream to be treated pass sequentially through following process steps,waste water treatment with hydrogen peroxide (H.sub.2 O.sub.2), irradiating at the same time with UV light,treatment with a reducing agent such as sodium dithionite,precipitation of existing metal contaminants, optionally followed by a filtration and/or a treatment with a selective ion exchanger.

Abstract: A process for purifying streams which contain organic and/or inorganic impurities is disclosed. The stream to be treated is introduced into a water-containing reaction zone which includes a packed bed of activated carbon to which an electrochemical potential is applied and to which ozone or hydrogen is fed at the same time. The cell further uses a contact electrode placed in the packed bed for supplying or removing an electrical current, and a counterelectrode disposed in a reaction vessel. The counterelectrode is electrically insulated from the packed bed of activated carbon. The cell further includes an inlet for feeding in liquid to be treated, an inlet for feeding ozone or hydrogen gas, and an outlet for discharging treated liquid and a further outlet for discharging waste gas.

Abstract: The action of the bacterium Nitrobacter agilis to oxidize nitrite ions to nitrate ions in aqueous solutions is well known. We have found that if the nitrite ion concentration in solution is maintained at a level of at least 2.5 percent by weight and higher, that the activity of this bacterium is completely inhibited and the nitrite salt solutions remain stable over long periods of time.

Abstract: The present invention relates to a method for the purification of contaminated fluids by photocatalytic treatment. In accordance with the invention, an oxidation state where contaminant molecules are oxidized and/or a reduction state where contaminant molecules are reduced are employed to purify a contaminated fluid. The reduction state, where certain contaminant molecules are reduced, is induced by providing a reactant, such as citric acid, in the presence of an excited photocatalyst. A reduction state may alternate to an oxidation state, where contaminant molecules are oxidized, by the addition of an oxidizing agent, such as oxygen.

Abstract: This invention relates to a process for reducing the sulfur in a refinery process stream and/or crude oil, which comprises treating said refinery process stream and/or crude oil with an effective sulfur reducing amount of a reducing agent selected from the group consisting of hydrazine, oximes, hydroxylamines, carbohydrazide, erythorbic acid, and mixtures thereof wherein the reducing agent or the hydrocarbon treated has a temperature of at least 50.degree. C.

Abstract: The improved method achieves effective and economical decomposition of hydrogen peroxide and may be used in recycling hydrogen peroxide-containing spent sulfuric acid that has been used in wafer cleaning and other operations in the process of semiconductor fabrication or in removing residual hydrogen peroxide that will occur either within the papermaking process or in plant effluents as a consequence of a shift from chlorine-containing bleaching agents to oxygen-containing bleaching agents.When coke was added in an amount of 10 wt % to a solution of 0.88 wt % hydrogen peroxide in 72.6 wt % sulfuric acid, followed by treatment at 60.degree.-70.degree. C. for 4 hours, the concentration of hydrogen peroxide dropped to 0.0001 wt % and below. When coke was added in an amount of 10 wt % to each of a solution (pH, 0.94) of 1.0 wt % hydrogen peroxide in 1.1 wt % sulfuric acid and a solution (pH, 2.58) of 1.04 wt % hydrogen peroxide in sulfuric acid followed by treatment at 60.degree.-70.degree. C.

Abstract: The present method is capable of completely neutralizing the aldehydes in aldehydic waste waters within about 15 minutes and of producing a non-toxic waste water which then can be disposed of without fear of contamination of drain lines, etc. The method is carried out by contacting aldehyde-containing waste water with a sufficient amount of sodium pyrosulfite to completely neutralize the aldehydes in the waste water within about 15 minutes to non-toxic substances. The contacting is initiated without first adjusting the pH of the waste water and is maintained during the treatment period with agitation of the waste water being treated to assure full neutralization of all parts thereof. The sodium pyrosulfite and its reaction products are non-toxic. No hazard label is required for the sodium pyrosulfite, in contrast to certain conventional waste treating chemicals. The sodium pyrosulfite is a white crystalline powder easily stored, handled, weighed out and used without danger.

Abstract: A method is provided for remediation of contaminated solutions using a tiered metal wall or column. The tiered metal wall or column has at least three zones with graduated sizes of reducing metal particles. Contaminated solutions pass through the tiered wall or column to dehalogenate contaminant halogenated hydrocarbons.