Abstract: Improvement in the enrichment of a gas in hydrogen sulphide, comprising selective absorption by a liquid in a primary absorption zone, regeneration of the liquid by heating and/or stripping by an inert gas with liberation of the gases absorbed and recovery of a fraction of the liberated gases, the remainder being subjected to a second absorption in a secondary absorption zone by a new or regenerated absorbent liquid identical with that used in the primary absorption zone; in one and the same zone of operation, common to the regeneration and the secondary absorption zones, there occur simultaneously: arrival of the liquid from the first absorption, movement of the gases liberated during regeneration, flow of the liquid derived from the secondary absorption and discharge of a fraction of the liberated gases enriched in H.sub.2 S.

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 for the removal of H.sub.2 S from a sour gaseous stream is disclosed, the process being characterized by the reaction of the H.sub.2 S to sulfur employing aqueous solutions of oxidizing polyvalent metal chelates of specified organic acids, and by the recovery of the sulfur from the solutions with specific extractants. The extractants are selected from compounds (and mixtures thereof) having the formula C.sub.n H.sub.2(n+1), wherein n is a whole number from 4 through 8, and the recovery may be made prior or subsequent to regeneration of the polyvalent metal chelate solution.

Abstract: An improved coke oven gas washing process for removing hydrogen sulfide is proposed wherein the coke oven gas is treated in a hydrogen sulfide scrubber by counterflow with an aqueous ammonia wash water. A stream of aqueous weak ammonia liquor is cooled and sprayed through nozzles in the mid-region of the hydrogen sulfide scrubber. A quantity of aqueous ammonia liquor, corresponding to the quantity which is sprayed through the said nozzles, is withdrawn from the hydrogen sulfide scrubber at a level below the nozzles and is introduced into the top of the said hydrogen sulfide scrubber. Ammonia vapor released at the nozzles has a higher partial pressure than the ammonia partial pressure of the coke oven gas in the region of the nozzle. The aqueous ammonia liquor from the deacidifier is the source of the cooled aqueous ammonia liquor which is introduced through the nozzles.

Abstract: A cyclic process for the removal of H.sub.2 S from a sour gaseous stream is disclosed, the process being characterized by the reaction of the H.sub.2 S to sulfur employing aqueous solutions of oxidizing polyvalent metal chelates of nitrilotriacetic acid, and by the recovery of the sulfur from the solutions with specific extractants. The extractants are selected from compounds (and mixtures thereof) having the formula C.sub.n H.sub.2(n+l), wherein n is a whole number from 4 through 8, and the recovery may be made prior or subsequent to regeneration of the polyvalent metal chelate solution.

Abstract: The NH.sub.3 content is regulated in methanol used in a process for scrubbing out sour gases from gaseous mixtures and/or for preventing ice formation prior to the scrubbing step. The methanol is freed, after the scrubbing step, respectively of absorbed gaseous components and/or water, and reused in the cycle as scrubbing liquid and/or for preventing ice formation. A strong acid is added to the methanol from water-soluble ammonium salts. Thereby, dissolved salts are formed which are removed together with water. Deleterious trace acids are also removed by an analogous treatment with a basic compound. The acid/base treatments are conducted in succession.

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: Process for the removal of hydrogen sulfide from gas mixtures, particular gas mixtures containing hydrocarbons, wherein the gas mixture is treated with an aqueous solution of a water soluble nitrite such as sodium nitrite, the pH of the aqueous solution being at least 5.5 or greater.

Abstract: A catalyst process is disclosed for the reduction of the ignition temperature of Diesel soot filtered out of the exhaust gas of Diesel engines by passing the exhaust gas over a catalytically active substance, which is selected from lithium oxide, copper chloride, vanadium oxide/alkali metal oxide combinations, a vanadate of an alkali metal or of cerium, or a silver or alkali metal perrhenate, preferably of sodium or silver, or mixtures of these substances.

Abstract: Waste gases resulting from the production of silicon in connection with the ormation or decomposition of chlorosilanes, which gases always contain hydrogen chloride, can be worked up without removal of the hydrogen chloride. For this purpose, the waste gases which, after separation from the chlorosilanes, only contain hydrogen and hydrogen chloride, are subjected to combustion with addition of air and, after addition of silicon tetrachloride, the result being highly dispersed SiO.sub.2. The hydrogen chloride then remaining in the gaseous phase is returned to the process stream for production of trichlorosilane.

Abstract: This invention provides a process for recovering alkanolamines, e.g. diisopropanolamine, from their corresponding cyclic reaction products (e.g., oxazolidinones), which products are the result of the reaction of CO.sub.2 and the alkanolamine, a situation commonly encountered in acid gas removal processes employing the alkanolamines alone or in combination with other liquids such as sulfolane (tetrahydrothiophene-1,1-dioxide). The process involves hydrolyzing the oxazolidinones in the presence of a small but catalytically effective amount of an amine, preferably from about 2 to 10 weight percent, based on 2-oxazolidinones. Preferably, the amine is the alkanolamine precursor of the corresponding 2-oxazolidinone.

Abstract: Metal bromides, and particularly alkaline earth metal bromides, are prepared from an alkaline earth metal compound and bromine in the presence of added lower alkanol as a reducing agent.

Abstract: A method and device for conducting gettering. The gettering is conducted with one of an LiB, LiSi or LiAl system. Preferably the LiB system is of the formula Li.sub.x B.sub.1-x wherein 0<x<1 with gettering conducted at room or slightly elevated temperature of about 100.degree.-200.degree. C.

Abstract: A process is disclosed for the elimination of waste water falling out with the desulfurization of coking oven gas by means of an organic oxygen carrier--containing washing solution with simultaneous recovery of elemental sulfur. The waste water is decomposed in a combustion chamber in a reducing atmosphere at temperatures between about 1000.degree. and 1100.degree. C. under such conditions that the mole ratio of H.sub.2 S:SO.sub.2 in the exhaust gas of the combustion chamber amounts to at least 2:1. Sulfur falling out is separated and the sensible heat of the exhaust gas is utilized for steam generation. The cooled and desulfurized exhaust gas is added to the coking oven gas before the pre-cooling. Sulfur falling out from the washing solution in the oxidizer is separated out and lead into the combustion chamber together with the part of the washing solution discharged as waste water from the washing solution circulation.

Abstract: A Stretford process for removing hydrogen sulfide collects a horizontal pool of liquid downstream of the primary gas/liquid contactor and accelerates a multiphase flow along the surface of that pool and along a serpentine path. Additional gas-liquid contact is effected by the interaction of multiphase flow and structural components establishing the pool and causing the acceleration.

Abstract: An improved system for recovering CO.sub.2 from flue gases containing SO.sub.2 at low CO.sub.2 partial pressure. The system includes the use of K.sub.2 CO.sub.3 as the solvent, regeneration of the solvent, and removal of SO.sub.2 and SO.sub.4.

Abstract: An improvement in the Claus Process for producing sulfur by reaction of hydrogen sulfide with sulfur dioxide at elevated temperature in the presence of a porous catalyst is described. The improvement lies in employing a porous catalyst, preferably alumina, having a large surface area at least 40% of which is provided by pores having diameters over the range 40 A.degree. to 150 A.degree. or having at least 20% of its surface area provided by pores having diameters over the range 80 A.degree. to 150 A.degree..

Abstract: There is disclosed a method of using an exhaust gas catalyst for treatment of exhaust gases developed by burning a hydrocarbon fuel or a fuel containing hydrocarbon and alcohol blends in an internal combustion engine. These exhaust gases contain varying amounts of unburned hydrocarbons, carbon monoxide and oxides of nitrogen depending upon the operating conditions of an internal combustion engine. This specification teaches a method of using an improved catalyst composition in which a support medium is provided for supporting the catalyst system. This support medium has deposited thereon palladium and finely divided tungsten. Tungsten is present on the support media in a quantity such that tungsten is available to substantially all of the palladium on the support medium.

Abstract: A straight-through three reactor system and process produces acceptable levels of sulfur recovery from acid gas at a cost significantly less than that required for a standard modified four reactor Claus system. The system includes two conventional Claus reactors and one cold bed adsorption (CBA) reactor in series. Four condensers are provided, one disposed before each of the catalytic reactors, and one disposed after the CBA reactor. The system is designed to operate either in a recovery mode or in a regeneration mode. In the recovery mode, the reactors are in series and the last reactor is operated below dew point of sulfur (CBA reactor). In regeneration mode, effluent from the third condenser is heated in a first heat exchanger where effluent from the first catalytic reactor is used as the heat source. Sulfur is vaporized in the CBA reactor and is recovered in the fourth condenser. Effluent from the fourth condenser is then passed to an incinerator.

Abstract: A process for destroying waste alkali metal hypochlorite such as sodium hypochlorite is disclosed. The process involves reacting 50-90% and preferably 70-90% of the alkali metal hypochlorite with urea at from 20.degree.-60.degree. C. and pH 6-8 with pH 7-8 being preferred. The remaining alkali metal hypochlorite can be destroyed with a reactant such as sulfur dioxide, sodium sulfite, or sodium thiosulfate.