Abstract: Hydrides of As, B, P, Sb or Se in a gas can easily be removed from the gas by contacting the gas with an adsorbent consisting of activated carbon containing:(1) copper oxide and(2) at least one of (a), (b) and (c) selected from the group consisting of(a) at least one alkali metal compound, and(b) at least one alkaline earth metal compound and(c) at least one compound of Al, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Cd and Pb.

Abstract: Disclosed is a transition metal component of a Ziegler-Natta catalyst which is composed of a titanium halide deposited on an essentially anhydrous magnesium chloride support. An improved support is prepared by contacting a hydrocarbon solution of magnesium alkanoate and a hydrocarbon solution of alkylaluminum dichloride in a liquid hydrocarbon reaction medium containing alkylaluminum dichloride and alkylaluminum alkanoate chloride. After workup and treatment with the titanium halide, the transition metal component is used in the Ziegler-Natta catalysis polymerization of 1-olefins. The resulting polyolefins have a narrow particle size distribution and a high bulk density.

Abstract: A process for treating iron chloride wastes such as those obtained when chlorinating titanium ore is disclosed. The process involves reacting the iron chlorides with limestone in molten CaCl.sub.2.xH.sub.2 O, where x equals 3-6 and separating the resulting iron oxide from the molten CaCl.sub.2.xH.sub.2 O.

Abstract: A method, applicable to hydrogen sulfide removal systems which employ a regenerable aqueous washing solution capable of absorbing hydrogen sulfide and converting that hydrogen sulfide to elemental sulfur, is provided for reconditioning such systems after they have become contaminated with sulfur-feeding bacteria and/or for maintaining such systems substantially free of such bacteria. In the method of the invention, the aqueous washing solution is contacted with an aliphatic dialdehyde.

Abstract: Industrial waste gases containing objectionable/polluting compounds of sulfur, e.g., H.sub.2 S, SO.sub.2 and such organosulfur derivatives as COS, CS.sub.2 and mercaptans, are catalytically desulfurized, e.g., by Claus process, employing an improved catalyst comprising titanium dioxide and calcium, barium, strontium or magnesium sulfate.

Abstract: A process for the removal of hydrogen sulfide from a gas which comprises contacting the gas with a solution comprising ferric ions (Fe.sup.3+) and ferrous ions (Fe.sup.2+). The solution further comprises ethylenediamine tetraacetic acid (EDTA) or a salt thereof and triethanolamine (TEA) or a salt thereof. The solution has a pH in the range of from 7 to 9 and a mole ratio of ferric ion to total iron ions in the range of from 0.60 to 0.90 as measured just after the hydrogen sulfide contacts the solution. The process is characterized by high removal of hydrogen sulfide, prevention of side reactions, and the inhibition of the formation of intermediate colloidal sulfur.

Abstract: The gas which contains sulfur compounds consisting of H.sub.2 S and/or COS is scrubbed with an absorbent solution which contains at least one amine. The gas to be desulfurized which enters the scrubbing zone is at a temperature in the range of 25.degree. to 100.degree. C. and rises in the scrubbing zone in a countercurrent to the scrubbing solution. The gas leaving the absorbent solution is indirectly cooled to a temperature which is at least 20.degree. C. below the entrance temperature of the gas and is not below 5.degree. C. The indirect cooling results in a condensate, which contains at least one secondary amine. That condensate is passed through the scrubbing zone as an absorbent solution. The condensate leaving the scrubbing zone contains at least 10 moles secondary amine and preferably at least 100 moles secondary amine per mole H.sub.2 S and COS in the gas to be desulfurized.

Abstract: A process and system are disclosed for the bridging of operational standstills of an ammonia washer of a plant operating according to the semi-direct technique for the removal of ammonia from coking oven gas. During the operational standstills of the ammonia washer, the ammonia is washed out from the coking oven gas in a secondary cooler constituting three parts, an upper part (Wash Stage I) provided with stripped water from an ammonia still, a middle part (wash stage II) provided with gas water, and a lower part (wash stage III) provided with circulation water. All of the waters provided for the secondary cooler are collected in its sump, and after a separation of the circulation water necessary for the Wash Stage III, it is split into two partial streams, one serving for the recovery of stripped water for Wash Stage I and which is led into an ammonia still provided only with water vapor and the other partial stream is led into an ammonia still provided with water vapor and alkali.

Abstract: A process for the simultaneous removal of H.sub.2 S, SO.sub.2 and elemental sulfur from gaseous mixtures, comprises treating the gaseous mixture with a solvent. After the solvent becomes loaded with the components to be removed, it is regenerated and reused. In order to obtain savings in costs and energy, the sulfur is separated from the loaded solvent by lowering the temperature thereof. In this way, chemical regeneration of the scrubbing medium takes place within the cycle eliminating the requirement for outside regenerating apparatus.

Abstract: This invention relates to a process for the reclamation of selenium in high purity from scrap alloys which comprises converting the alloy to a mixture of oxides, separating the selenium oxide formed by alcoholic dissolution, followed by treating this solution with a reducing agent, and thereafter separating the selenium product therefrom.

Abstract: Method of separating oxygen or nitrogen from air using as an oxygen acceptor composition a molten solution of alkali metal salt of a cation composition of sodium and potassium cations and an anion composition of 50 to 94% nitrate, 4 to 25% nitrite and combined oxide, peroxide and superoxide wherein said oxides are present in less than 1 mol % based on sodium peroxide.

Abstract: Disclosed is a process for the treatment of exhaust gas comprising a heating step using an external energy source which partially oxidizes the exhaust gas and a subsequent catalytic treating step.

Abstract: A process for removing hydrogen sulfide from geothermal steam and from vent streams, or concentrated portions produced by a hydrogen sulfide separation process, includes the steps of introducing an oxygen-containing gas, such as air into the steam, or vent stream, and thereafter contacting the steam and oxygen-containing gas in a contacting stage with iron oxide supported by a carrier resistant to deterioration. The steam having a temperature of at least 250.degree. F. is mixed with oxygen to provide a molar ratio of oxygen-to-hydrogen sulfide ratio of less than about 10. During the contacting stage the pressure of the steam and oxygen-containing gas is maintained at a pressure sufficient to enable removal of a majority of the hydrogen sulfide from the steam and oxygen-containing gas.

Abstract: In a continuous process for the removal of H.sub.2 S from a gaseous mixture involving: (a) simultaneous absorption and oxidation of H.sub.2 S to form elemental sulfur; (b) regeneration of the oxidizing agent, e.g., vanadate, by treating the used scrubbing liquid with air; and (c) recycling the regenerated scrubbing liquid to the scrubbing step, to avoid the formation of sulfates and thiosulfates, the dissolved oxygen is substantially prevented from appearing in the scrubbing solution before reuse.

Abstract: The Claus process gas is cooled in a condenser to condense most of the sulfur vapor in solid form. The gas leaving the condenser is then further cooled to condense water without producing substantially any sulfur in an undesirable form. The resulting gas of reduced water content is useful in Claus reaction, particularly the low temperature Claus reaction in which the product sulfur is adsorbed on the catalyst.

Abstract: An indirect hydrogen sulfide conversion process for the production of elemental hydrogen and sulfur. The process is based upon the electrochemical oxidation of iodide in an aqueous solution with a pH in the range of 0 to 1 at high current densities and current efficiencies. Hydrogen gas is produced concurrently with soluble triiodide. Treatment of a gaseous or non-aqueous liquid stream with electrolyte solutions containing triiodide yields a sulfur product in plastic form. The sulfur product can be recrystallized from a solvent to yield sulfur of comparable purity to that presently produced.

Abstract: A catalyst suitable for the catalysis of the oxidation of carbon monoxide is prepared by providing the substrate with tin (IV) oxide support material and with a catalytically active material.The tin (IV) oxide is provided by contacting the substrate with a dispersion of colloidal or non-colloidal particles in a liquid medium, said dispersion being convertible to tin (IV) oxide by drying and firing, followed by drying and firing. A catalyst can be so-produced having low flow resistance, high low temperature activity and relative insensitivity to deactivation by moisture. The dispersion may, for example, be a tin (IV) oxide aqua-sol made, for example, by peptising hydrated stannic oxide with a quaternary ammonium hydroxide.

Abstract: High-performance carbon fiber or graphite fiber can be produced by treating the preoxidized fiber or carbon fiber strand with an aqueous solution containing at least one member of polyethylene oxide having a molecular weight greater than 100,000, methyl cellulose, ethyl cellulose, and hydroxyethyl cellulose, and drying the treated fiber strand at a temperature lower than 250.degree. C. prior to carbonization or graphitization.

Abstract: Gases containing CO and/or CO.sub.2 are purified by removing sulfur compounds and other impurities by catalytic reaction at elevated temperatures by a process in which the gases to be purified are passed directly through a catalyst charge containing a Cu/ZnO catalyst prepared by thermal decomposition of a mixed crystalline compound of zinc hydroxide carbonate, and the space velocity is set at 500-5,000 m.sup.3 (S.T.P.) per m.sup.3 of catalyst per hour. Preferably, the catalyst used is a Cu/ZnO catalyst which is prepared by thermal decomposition of a catalyst precursor of the general formulaCu.sub.x Zn.sub.y (OH).sub.6 (CO.sub.3).sub.2.

Abstract: A process for purifying gases from hydrogen sulphide which comprises oxidation of hydrogen sulphide with air oxygen at a volume ratio between hydrogen sulphide to oxygen equal to 1:1-1.5 on a catalyst having the following composition, % by weight: titanium dioxide--10-30, iron oxide--20-30, zinc oxide--20-25, chromium oxide--20-50. The process is conducted at a temperature within the range of from 220.degree. to 260.degree. C. and at a space velocity of the gas mixture of from 3,000 to 15,000 hr.sup.-1.