Abstract: A single step process for degrading plastic waste by converting the plastic waste into carbonaceous products via thermal decomposition of the plastic waste by placing the plastic waste into a reactor, heating the plastic waste under an inert or air atmosphere until the temperature of about 700° C. is achieved, allowing the reactor to cool down, and recovering the resulting decomposition products therefrom. The decomposition products that this process yields are carbonaceous materials, and more specifically carbon nanotubes having a partially filled core (encapsulated) adjacent to one end of the nanotube. Additionally, in the presence of a transition metal compound, this thermal decomposition process produces multi-walled carbon nanotubes.

Abstract: Dry-scrubbing media compositions, methods of preparing same, and methods of use are provided. The compositions contain activated alumina and potassium carbonate. Optionally, activated carbon and other impregnates, such as sulfates of group 1A metals, are included in the compositions. The compositions exhibit improved efficiency and capacity for the removal of compounds such as chlorine or sulfur dioxide from an air-stream. The compositions are particularly useful for reducing or preventing the release of toxic gaseous compounds from the areas such as petroleum storage areas, refineries, drinking water systems, sewage treatment facilities, swimming pools, hospital morgues, animal rooms, and pulp and paper production sites.

Abstract: The present invention relates to a system and process utilizing ammonium thio sulfate solution (ATS) as the primary liquid absorption agent that is re-circulated through an SO2 Contactor/Absorber for high efficiency contacting and absorption of sulfur dioxide, SO2 from a combustion gas stream generated by incineration of a Claus Sulfur Recovery Unit (SRU) off gas stream (often referred to as a Claus tail gas stream) and also additional SO2 generated from incineration of additional sulfur containing streams. ATS is also re-circulated through a separate H2S Contactor/Absorber for absorption of and reaction with a Sour Water Stripper (SWS) off gas stream and additional H2S-Acid Gas (A.G.) streams to produce additional concentrated ATS. The process and equipment also provides the ability to readily switch between using ATS and ABS as the primary absorbent solution for SO2 absorption, depending upon the concentration of SO2 in the off gas feed streams.

Abstract: The present invention relates to a system and process utilizing ammonium thiosulfate solution (ATS) as the primary liquid absorption agent that is re-circulated through an SO2 Contactor/Absorber for high efficiency contacting and absorption of sulfur dioxide, SO2 from a combustion gas stream generated by incineration of a Claus Sulfur Recovery Unit (SRU) off gas stream (often referred to as a Claus tail gas stream) and also additional SO2 generated from incineration of additional sulfur containing streams. ATS is also re-circulated through a separate H2S Contactor/Absorber for absorption of and reaction with a Sour Water Stripper (SWS) off gas stream and additional H2S-Acid Gas (A.G.) streams to produce additional concentrated ATS. The process and equipment also provides the ability to readily switch between using ATS and ABS as the primary absorbent solution for SO2 absorption, depending upon the concentration of SO2 in the off gas feed streams.

Abstract: A process for substantially removing carbonaceous material from a composition comprising providing the composition having carbonaceous material, reacting the carbonaceous material with a sulfur compound, and forming products having carbon and sulfur, and the resulting composition and system used therefore.

Abstract: The present invention relates to a catalyst for purifying an exhaust gas, and in particular provides a catalyst for purifying an exhaust gas using a complex oxide, which is not deteriorated in its purifying performance even in a lean atmosphere containing sulfur dioxide SO.sub.2 at temperatures as high as at least 1,000.degree. C., comprising at least one of the noble metals and one or at least two elements selected from the group consisting of alkaline earth metals and Group IIIA elements, and at least one member selected from the group consisting of iron, nickel and cobalt is supported in the surface portion of the catalyst, the catalyst further comprising, as a constituent element of the complex oxide, at least one element selected from the group consisting of iron, nickel and cobalt.

Abstract: An apparatus and a method for measuring head speed and an opening angle. At least four sensors are disposed at each vertex of a defined rectangle. An instrumentation device measures differences in time between instants in which a moving head intercepts rays of light toward the sensors, respectively. An arithmetic unit calculates head speed and an opening angle on the basis of the measured time differences.

Abstract: A method for refining liquified petroleum gases so that gases can be treated to reduce odor, olefins, moisture and wherein side reactions are minimized to produce stable aerosol by multistage liquid-liquid extraction of the aerosol using electrolyte solutions at controlled pH, chemically treating, drying and finishing by using molecular sieves and metal sulfides.

Abstract: A process for removal of H.sub.2 S from gas streams is described, the process being characterized by use of a novel iron chelate treating solution containing a specified ferric to ferrous chelate ratio and aqueous ammonia.

Abstract: A process for removal of H.sub.2 S from gas streams is described, the process being characterized by use of a novel iron chelate treating solution containing a specified ferric to ferrous chelate ratio, aqueous ammonia, and thiosulfate ion.

Abstract: The invention provides a process for the selective absorption of chlorine from CO.sub.2 -containing off-gases, which comprises washing the off-gases with an aqueous solution which contains 0.1-10% by weight of NaHCO.sub.3 and 0.01-5% by weight of NaHSO.sub.3.

Abstract: A process for purifying an aqueous, hydrogen sulfide-scrubbing solution which contains a water-soluble transition metal component, such as a vanadium component or an iron component, in addition to at least one water-soluble organic compound, such as an aromatic sulfonate or an alkanolamine, in which the scrubbing solution is mixed with particles of a spent solid catalyst containing molybdenum and aluminum and a basic aqueous solution, preferably a solution comprising sodium aluminate, to form a slurry which is subsequently contacted with an oxygen-containing gas under conditions such that the molybdenum in the catalyst is solubilized. Thereafter, molybdenum is precipitated from the solution along with the water-soluble transition metal component and a wastewater substantially free of the transition metal component and the organic compound originally present in the scrubbing solution is recovered.

Abstract: A process for removal of H.sub.2 S from gas streams is described, the process being characterized by use of a novel iron chelate treating solution containing a specified ferric to ferrous chelate ratio, aqueous ammonia, and thiosulfate ion.

Abstract: A process for removal of H.sub.2 S from gas streams is described, the process being characterized by use of a novel iron chelate treating solution containing a specified ferric to ferrous chelate ratio and aqueous ammonia.

Abstract: There is disclosed a composite immobulized liquid membrane of a solvent-swollen polymer and a microporous organic or inorganic support, the solvent being at least one highly polar solvent containing at least one nitrogen, oxygen, phosphorous or sulfur atom, and having a boiling point of at least 100.degree. C. and a specified solubility parameter. The solvent or solvent mixture is homogeneously distributed through the solvent-swollen polymer from 20% to 95% by weight. The membrane is suitable for acid gas scrubbing and oxygen/nitrogen separation.

Abstract: The present invention is directed to a process for removing H.sub.2 S from a gaseous stream, preferably a natural gas stream, which comprises forming a buffered aqueous H.sub.2 S stream containing thiosulfate by contacting the gaseous stream with water containing a buffering agent and thiosulfate to remove the H.sub.2 S from the other gases in the gaseous stream; introducing the buffered aqueous H.sub.2 S stream into a reduction section under conditions wherein elemental sulphur is produced and removing an effluent stream from the reduction section; introducing the reduction section effluent into an oxidation section and contacting the effluent with air to react the oxygen in the air with the H.sub.

Abstract: A composite immobilized liquid membrane suitable for acid gas scrubbing is disclosed. The membrane is a solvent-swollen polymer and a microporous polymeric support, the solvent being selected from a class of highly polar solvents containing at least one atom selected from nitrogen, oxygen, phosphorous and sulfur, and having a boiling point of at least 100.degree. C. and a solubility parameter of from about 7.5 to about 13.5 (cal/cm.sup.3 -atm).sup.1/2. Such solvents are homogeneously distributed through the solvent-swollen polymer from 20% to 95% by weight. Also disclosed are methods of acid gas scrubbing of high- and low-Btu gas effluents with such solvent-swollen membranes.

Abstract: A process for recovering elemental sulfur from a hydrogen sulfide containing gas stream by reacting the hydrogen sulfide in the gas stream with a buffered aqueous solution enriched in thiosulfate ions at an initial pH between about 4.5 and 6.5 for residence time to sufficiently react a portion of the hydrogen sulfide to elemental sulfur. The elemental sulfur is then removed and the solution now lean in thiosulfate ions is regenerated by the oxidation of the remaining hydrogen sulfide in the gas stream to deplete the hydrogen sulfide from the gas stream and to regenerate the liquid solution for recycling to the reduction zone.

Abstract: A cyclic process and composition for the removal of hydrogen sulfide from a variety of gas streams is disclosed. The gas stream containing the sour gases is contacted with a specified reactant solution and a combination crystal modifier of phosphate and thiosulfate ions. The hydrogen sulfide is converted to sulfur, and the reactant is reduced. The process includes sulfur removal and regeneration of the reactant.

Abstract: A cyclic process and composition for the removal of hydrogen sulfide from a variety of gas streams is disclosed. The gas stream containing the sour gases is contacted with a specified reactant solution and a combination crystal modifier of phosphate and thiosulfate ions. The hydrogen sulfide is converted to sulfur, and the reactant is reduced. The process includes sulfur removal and regeneration of the reactant.

Abstract: A gas treating process is disclosed. Hydrogen sulfide and carbon dioxide are removed from a hydrocarbon vapor stream by absorption into an aqueous carbonate solution. Hydrogen sulfide picked up by the circulating carbonate solution is oxidized to produce liquid sulfur, which is withdrawn. The carbonate solution is then stripped to release carbon dioxide and produce the lean carbonate solution used for absorption. By-product thiosulfate formed in the oxidation step is eliminated by reaction with hydrogen sulfide. Metal phthalocyanines are used as the catalyst for the elimination of thiosulfate and for the oxidation of hydrogen sulfide.

Abstract: At least one of sulfur dioxide and a gaseous hydrosulfide is contacted with at least one of a sulfur-containing salt and a gaseous basic nitrogen compound to produce a solid, sulfur-containing composition.

Abstract: A process is disclosed in which a waste gas containing sulfur compounds and carbon dioxide from pulp mill is contacted with an aqueous alkali solution derived from green liquor, white liquor or weak white liquor having low pH value and low sodium ion concentration and having been oxidized, whereby the sulfur compounds are absorbed as completely as possible with minimal absorption of carbon dioxide in the waste gas.

Abstract: Sulfur compounds contained in gases containing oxygen and a high content of water vapor are exploited by removing the water vapor content by treating the gases with a glycol and then using the dried gas still containing sulfur compounds, as an oxidation gas for the burning of sulfur or for the roasting of sulfidic ores in the production of highly concentrated sulfuric acid. Apparatus for carrying out the process includes an absorber for absorption by the glycol of the water vapor contained in the gas. The absorber has an exhaust gas conduit connected to a combustion furnace or roasting furnace for the production of sulfur dioxide. A desorber is provided for distilling the water vapor from the glycol and is connected to the absorber by a ring conduit for the glycol enriched with water and for the dewatered glycol. Lastly, apparatus is provided for the heating of the glycol and the desorber.

Abstract: An oxygen absorbent composition consisting essentially of (a) an oxygen absorbent comprising a dithonite as a main component and (b) a fiber material in an amount of from about 1 to about 50 parts by weight per 100 parts by weight of the oxygen absorbent and a process for producing the same are disclosed.

Abstract: An oxygen absorbent comprising a dithionite and at least one compound having water of crystallization or water of hydration is disclosed.

Abstract: An effective oxygen-consuming composition for packages, containers, or other closed spaces, especially containing an article susceptible to oxidative deterioration, comprises a dithionite for reacting with oxygen, sufficient alkaline material to at least partially neutralize sulfur dioxide released as a by-product of the oxygen consuming reaction, and porous filler particles in sufficient amount to promote contact with the ambient atmosphere, all in homogeneous mixture.

Abstract: A process is provided for reducing the requirement of fresh chemicals without increasing emissions in the pulping of cellulosic material with alkaline sodium- and sulfur-containing-sulfate pulping liquor, which comprises evaporating and burning spent sulfate pulping liquor to obtain a smelt; dissolving the resulting smelt in water to form a sodium-sulfide-sodium carbonate-containing solution green liquor; regenerating pulping white liquor containing sodium sulfide and sodium hydroxide from said green liquor; and recirculating said regenerated white liquor to the pulping stage; oxidizing at least one of the resulting green and white liquors to form sodium thiosulfate therein; reacting the oxidized liquor with residual acid liquor, from the manufacture of chlorine dioxide by reduction of an alkali metal chlorate solution, to convert thiosulfate to sulfur dioxide and sulfur; removing and recovering formed sulfur dioxide; and returning the residual liquor, freed from sulfur dioxide, to the pulping.

Abstract: Ammonia, hydrogen cyanide and hydrogen sulfide contained in gas streams are separated from the gas streams by contacting the gas stream with an aqueous solution containing free oxygen for a time sufficient for the ammonia, hydrogen sulfide and hydrogen cyanide to react with the oxygen present to form ammonium thiocyanate and water for further treatment or disposal.One method of treatment is to thermally and catalytically convert for the ammonium thiocyanate to ammonia or nitrogen and hydrogen sulfide in the form of a second gas stream which is processed for recovery of any formed ammonia and the hydrogen sulfide.