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: Gas mixtures containing a substantial amount of CO.sub.2 are treated to remove H.sub.2 S by using a selective solvent containing CO.sub.2, usually obtained by understripping loaded solvent during regeneration.

Abstract: There is described a simple two compartment electrochemical cell which may be associated in multiples in parallel for electrochemically freeing alkanolamines of the heat stable salt forming anions found or formed in acid gas conditioning thermal regenerative sorbent processes using alkanolamines as sorbents for acid gases, the cell having an anion exchange membrane separating the cell into two compartments and an anode comprised of an iridium coated electroconductive metal electrode.

Abstract: There is described a simple two compartment electrochemical cell which may be associated in multiples in parallel for electrochemically freeing alkanolamines of the heat stable salt forming anions found or formed in acid gas conditioning thermal regenerative sorbent processes using alkanolamines as sorbents for acid gases, the cell having an anion exchange membrane separating the cell into two compartments and an anode comprised of platinum or a platinum coated electroconductive metal electrode.

Abstract: There is disclosed a process for treating liquid (liquifiable) and gaseous hydrocarbons to remove substantially all of the acid gases including COS by contacting the hydrocarbon streams with specific aqueous treating agents in a series of sequential specific limit operations and apparatus.

Abstract: An improved method for amine regeneration wherein a rich amine out of a first heat exchanger is temperature controlled prior to transfer to a second heat exchanger. At least a portion of the hot overhead gasses exiting from a stripping still are transferred to the second heat exchanger. Temperature controlled heated rich amine liquid passes through the second exchanger and contacts the hot overhead gasses. The rich amine liquid is increased in higher temperature thereby and then is transferred to yet a third exchanger and finally to the stripping still for regeneration of lean amine. The reduced temperature overhead gasses are transferred to the reflux condensor for final cooling.

Abstract: Improvement are provided in accordance with the present invention by a continuous process for the treating of a gas stream containing acid gas components wherein the gas stream is counter currently contacted in an absorption zone with an aqueous solution of a mixture of N-methyldiethanolamine with imidazole or a methyl substituted imidazole to thereby provide for acid gas (e.g., CO.sub.2) absorption.

Abstract: The disclosed method for the selective removal of H.sub.2 S from a H.sub.2 S-containing gas comprises contacting the gas in an absorption area (1) with a selective regeneratable absorbing liquid which absorbs the H.sub.2 S and regenerating by heating the absorbing liquid laden with H.sub.2 S in a regeneration area (3). The absorbing liquid coming out of the area (1) is sent to an enrichment area (2) through a conduit (25), a portion of the gases at the head of the area (3) is tapped through a valve (27) to form an acid gas flow enriched with H.sub.2 S and the remainder is introduced in the area (2) through a conduit (29), the absorbing liquid is tapped at the bottom of the area (2) and introduced through a conduit (25) in the area (3) and a gas stream is collected at the head of the area (2) and is injected through a conduit (22) in the area (1). Application to the simultaneous production of a gas flow highly enriched with H.sub.2 S and a gas having a fixed minimum content of H.sub.2 S.

Abstract: H.sub.2 S is removed from substantially supercritical CO.sub.2 by contact with a sorbent solution comprising (a) a tertiary amine; (b) particular physical co-sorbent; and (c) 3-10% w water.

Abstract: In an alkanolamine gas treating process for removing acid gas from a feedstream in which hydrogen sulfide is present, reduced corrosion of steel parts or components is observed when solution concentrations of hydrogen sulfide and vanadium in the plus five valence state are maintained above certain minimum levels.

Abstract: A permeant gas is selectively transferred from a feed-gas mixture which comprises the permeant gas and at least one other component to an output fluid by the process of the invention. The process involves introducing a selective-permeation liquid into a permeation-transfer chamber. A gas-depletion channel and a gas-enrichment channel pass through the permeation chamber and are separated from the chamber respectively by porous walls. The selective-permeation liquid contacts the porous walls but does not flow into the gas-depletion or gas-enrichment channels. The feed-gas mixture is introduced into the gas-depletion channel so that permeant gas in the mixture can pass through the pores of the walls of the channel into the selective-permeation liquid and from the selective-permeation liquid through the pores of the walls of the gas-enrichment channel into the gas-enrichment channel.

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: The invention relates to a process for the removal of acid gases from gaseous mixtures wherein said mixture is contacted with an aqueous alkaline solution comprising a compound of an alkali metal or ammonia and an alkanolamine-based promoter characterized in that the promoter is a mixture of at least one secondary alkanolamine and at least one N-alkyl-2-aminoethanol, said alkyl radical containing up to 3 carbon atoms.

Abstract: Brass, bronze and other mixture of copper and zinc use used to treat alkanolamine solutions used in systems for separating CO.sub.2 from gaseous mixtures to give enhanced protection against ferrous metal corrosion.

Abstract: This invention discloses mixtures of alkyl dialcohol amines and mono alkyl ethers of polyethylene glycols which are useful in removing acidic gases from gaseous mixtures. The solvent mixtures contain between 1.5 N and 5.0 N methyl diethanolamine (MDEA), 10 to 40 percent water and the balance is methoxytriglycol (MTG). The overall heat of reaction of the solution is typically less than 500 BTU/lb CO.sub.2, and remains as a single liquid phase during normal gas scrubber operating conditions.

Abstract: The present invention is directed to an improved process for the removal of acid gases from gas mixtures which significantly decreases the consumption of heat needed for regenerating the rich alkaline scrubbing solution which is used to remove the acid gases from the gas mixtures. The process comprises passing one portion of the scrubbing solution through a steam stripping section and another portion of the scrubbing solution through a flashing section for regeneration wherein the overhead vapors from the steam stripping section are used to heat and strip the scrubbing solution in the flashing section and heat contained within the regenerated scrubbing solution coming from the steam stripping section is utilized to aid in the regeneration of the scrubbing solution in the flashing section.

Abstract: Improvements are provided in accordance with the present invention by a continuous process for the treating of a gas stream containing acid gas components wherein the gas stream is counter currently contacted in an absorption zone with an aqueous solution of a mixture of N-methyldiethanolamine with N,N-diethyl hydroxylamine to thereby provide for acid gas (e.g., CO.sub.2) absorption.

Abstract: Herein is described a technique for maintaining a copper ion in the plus 2 oxidation state, as it is employed as an inhibitor in an alkanolamine gas conditioning absorbent solution to provide corrosion protection of the metals in contact with the alkanolamine solution. The procedure disclosed for maintaining copper in the plus 2 state is to apply an induced or impressed voltage across a point, or several points, in the circulating copper containing solution of the gas conditioning plate for the recovery of CO.sub.2 from flue gas particularly when oxygen is present in the gas being treated.

Abstract: The process selectively absorbs hydrogen sulphide from gases containing hydrogen sulphide and carbon dioxide by contacting the gas with an aqueous solution of alkanolamine in an absorber column containing a structured packing consisting of a number of corrugated plates arranged parallel to the column axis. The corrugations are angled to the column axis at an angle between 20.degree. and 70.degree. and run in opposite directions on adjacent plates. The structured packing effects a lower absorption of the carbon dioxide in the solvent than Pall rings or sieve trays so that only a small amount of carbon dioxide is co-absorbed with the hydrogen sulphide.

Abstract: The invention relates to a process for the selective removal of hydrogen sulfide from a gaseous stream additionally containing carbon dioxide by contacting the gaseous stream with a polyvalent metal chelate solution for a time sufficient to allow the polyvalent metal chelate to oxidize the hydrogen sulfide to elemental sulfur without allowing the polyvalent metal chelate solution to absorb appreciable amounts of carbon dioxide. The pH of the metal chelate solution should be greater than 7 and the contact time between the polyvalent metal chelate and the gaseous stream is between 0.006 and 0.08 second.

Abstract: Process and composition for removing H.sub.2 S and like sulfides from gas streams by contact with a substituted aromatic nitrile having an electron-attracting substituent on the aromatic ring at least as strong as halogen (e.g., isophthalonitrile) and an organic tertiary amine in an inert organic solvent such as N-methyl-2-pyrrolidone.

Abstract: There is disclosed a procedure for removing copper inhibitor from a circulating fluid which contains the same, which copper may be lost on the cool side of a gas conditioning system by plating out under certain conditions, by contacting a portion of the circulating hot fluid with an activated carbon bed to sorb the copper in excess of the solubility limits within said fluid, regenerating said carbon bed when saturated by contacting said carbon bed with cool circulating fluid, thus returning copper which may have plated out to the circulating fluid in an amount and in an ionic state which will not plate out in the system, the circulating fluid is also treated on the cool side by mechanical filtration, activated carbon sorption and/or ion exchange to remove physical and chemical impurities, contaminates and degradation products.

Abstract: An alkaline absorbent composition comprising a severely hindered amino compound and an amine salt is provided. A process for the removal of H.sub.2 S from fluid mixtures using this absorbent composition to produce a very low level of H.sub.2 S in the treated fluid is also provided. The process is also suited for the selective removal of H.sub.2 S from fluid mixtures comprising H.sub.2 S and CO.sub.2.

Abstract: A gas scrubbing operation wherein a mixture of gases is scrubbed with a gas scrubbing medium to remove at least one gas component from the mixture is improved by reducing the fouling of apparatus used in the scrubbing operation by adding to the scrubbing medium an antifoulant effective amount of a hydroxylamine compound.

Abstract: A process is set forth for the selective removal of acid gases such as H.sub.2 S, COS and CO.sub.2 from a gas stream by contacting the stream with a bis tertiary amino alkyl solvent compound such as 4,4'-(oxydi-2,1-ethanediyl) bismorpholine. When used in an aqueous solution, the compounds catalytically hydrolyze COS to H.sub.2 S and CO.sub.2.

Abstract: There is disclosed a process for selectively separating hydrogen sulfide from gaseous mixtures which also contain carbon dioxide by chemical absorption with a substantially anhydrous solution of a tertiary amine, such as methyl diethanolamine, and an auxiliary organic solvent, such as sulfolane.

Abstract: Process and composition for removing H.sub.2 S and like sulfides from gas streams by contact with a substituted aromatic nitrile having an electron-attracting substituent on the aromatic ring at least as strong as halogen (e.g., isophthalonitrile) and an organic tertiary amine in an inert organic solvent such as N-methyl-2-pyrrolidone.

Abstract: CO.sub.2 and, where relevant, H.sub.2 S are removed from natural gases which contain CO.sub.2 and may or may not contain H.sub.2 S by a process in which the said natural gases are treated, in an absorption stage at from 40.degree. to 100.degree. C., with an aqueous absorption liquid containing from 20 to 70% by weight of methyldiethanolamine, the treated natural gases are taken off at the top of the absorption stage, the aqueous absorption liquid laden with CO.sub.2 and, where relevant, H.sub.2 S is taken off at the bottom of the absorption stage and then regenerated in one or more flash stages, and the regenerated absorption liquid is recycled to the absorption stage.

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: 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: 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: The selective removal of H.sub.2 S gas from a normally gaseous mixture containing H.sub.2 S and CO.sub.2 is accomplished by contacting the gaseous mixture with an absorbent solution comprising a strongly basic tertiary amino compound having a pK.sub.a at 20.degree. C. greater than 8.6 and a boiling point at 760 mm greater than 180.degree. C. whereby H.sub.2 S is selectively absorbed from the mixture.

Abstract: The selective removal of H.sub.2 S gas from a normally gaseous mixture containing H.sub.2 S and CO.sub.2 is accomplished by contacting the gaseous mixture with an absorbent solution comprising a nitrogen heterocyclic tertiary aminoalkanol or aminoetheralkanol whereby H.sub.2 S is selectively absorbed from the mixture.

Abstract: A method is disclosed for recovering carbon dioxide from gases containing the same as well as oxygen and/or sulfur compounds employing aqueous 5 to 80% alkanolamine solutions. Corrosion of the metals of construction and solvent degradation are minimized by the use of copper ion maintained in solution and continuous removal of ionic iron and solvent degradation products by treating the solvent or a portion of the solvent with a carbon bed, mechanical filter and/or a anion exchange resin.

Abstract: A novel class of severely sterically hindered secondary aminoether alcohols of the general formula: ##STR1## are prepared wherein R.sub.1 and R.sub.2 are each selected from the group consisting of alkyl and hydroxylalkyl radicals R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each selected from the group consisting of hydrogen, alkyl and hydroxyalkyl radicals, with the proviso that at least one of R.sub.4 or R.sub.5 bonded to the carbon atom directly bonded to the nitrogen atom is an alkyl or hydroxyalkyl radical when R.sub.3 is hydrogen, x and y are each positive integers ranging from 2-4 and z is a positive integer ranging from 1-4. The compounds are useful in the selective removal of H.sub.2 S from mixtures containing H.sub.2 S and CO.sub.2.

Abstract: Carbon dioxide is removed from CO.sub.2 and hydrocarbon containing gaseous streams. In the instance where the hydrocarbons and CO.sub.2 are such that hydrocarbons would condense out during CO.sub.2 removal, the gas stream is treated in one or more stages to accomplish hydrocarbon composition control.

Abstract: The invention relates to a finishing process for the removal of low level concentrations of mercaptans, sulfides and disulfides from a gas stream, especially a natural gas stream. The sulfur compounds are washed from the gas stream with a solution containing hydrogen peroxide, sodium carbonate or sodium hydroxide, and ammonia or an amine.

Abstract: Makeup water is distilled internally in an amine gas treating unit by adding it to the reclaimer used to process a slipstream of lean amine from the stripper.

Abstract: Process for regeneration of a solvent for preferentially absorbing acid gases. The solvent, which comprises between 5 and 55 percent by weight water, is steam stripped in a regenerator, and vapor leaving the regenerator with the acid gases is condensed. The resulting condensate is returned to the solvent downstream of the regeneration zone. The condensate may be partially or wholly recirculated to the upper part of the regenerator provided that the majority of it is withdrawn above the regeneration zone. Some of the condensate may be added back to the solvent at the bottom of the regenerator or in a reboiler associated with the regenerator.

Abstract: A corrosion inhibited composition containing an aqueous gas conditioning solution such as an alkanolamine with small amounts of soluble trivalent bismuth compounds. The compositions are useful to separate acid gases such as carbon dioxide from feed streams in gas conditioning apparatus with minimum amounts of corrosion of the stainless steel.

Abstract: A corrosion inhibited composition containing a gas conditioning solution such as an alkanol amine with water or with organic solvents and with small amounts of soluble thiocyanate compounds, soluble trivalent bismuth compounds with or without soluble divalent nickel or cobalt compounds. The compositions are useful to separate acid gases such as carbon dioxide from hydrocarbon feed streams in gas conditioning apparatus with minimum amounts of corrosion of the ferrous surfaces.

Abstract: Corrosion inhibiting compositions for use in aqueous absorbent gas-liquid contacting processes for recovering carbon dioxide (CO.sub.2) from industrial gas and oil combustion and partial combustion process flue gases, particularly employing copper carbonate, in combination with one or more of dihydroxyethylglycine, alkali metal permangenate, alkali metal thiocyanate, nickel or bismuth oxides with or without an alkali metal cartonate. The inhibitors are effective in reducing corrosion of metals in contact with the aqueous absorbent in the absorbent regeneration section of the plant as well as reduce the thermal degradation of the absorbent when high oxygen content combustion gases are treated to recover the CO.sub.2.

Abstract: There is disclosed a process for removing sulfur compounds from a gas stream. The process involves passing the gas stream containing the sulfur compounds through a mass of porous material that has deposited upon it a metal oxide, the improvement comprises the continuous or intermittent addition of an oxidizing agent and an amine.

Abstract: The removal of CO.sub.2 and mixtures thereof with H.sub.2 S from gaseous mixture containing same, is carried out by using an absorbing solution which comprises a first activating substance chosen from aminoacids and primary and secondary ethanolamines, which effects the initial absorption of CO.sub.2 with formation of a carbamate, a second activating substance chosen from As.sub.2 O.sub.3 and its derivatives, secondary ethanolamines and ammonia, which promotes the hydrolysis and decomposition of the carbamate as the latter forms, and a third substance of a basic nature, which effects the quantitative absorption of CO.sub.2 or CO.sub.2 +H.sub.2 S.

Abstract: The corrosion of ferrous metal surfaces in gas conditioning apparatus is inhibited by using a gas conditioning solution such as aqueous alkanolamines which contain thionitrogen compounds such as metal thiocyanates or thioamides. After recycling the gas conditioning solution for a few days, the solution dissolves sufficient amounts of nickel or cobalt or other metals in the equipment to act as a synergist with the thionitrogen compounds. In the event, the equipment does not contain any soluble synergistic metals, these metals may be added to the gas conditioning solution as soluble metal salts. Examples of useful additive metals are cobalt, nickel, calcium, copper, chromium, zinc, tin, aluminum, and magnesium.

Abstract: Process for separating H.sub.2 S from CO.sub.2, both contained in a treated gas, wherein said gas is contacted with a solution which selectively absorbs H.sub.2 S, wherefrom H.sub.2 S is separated in a regeneration zone, CO.sub.2 being released, said contact step being effected in a contact apparatus comprising 1 to 10 stages each formed of parallel vertical tubes whose bottom portion is provided with injection means of the cyclonic type imparting to the supplied gas and liquid a swirling ascending motion.

Abstract: A novel class of di-secondary aminoethers of the general formula: ##STR1## are disclosed wherein R.sub.1 and R.sub.8 are each independently selected from the group consisting of primary alkyl having 1 to 8 carbon atoms and primary hydroxyalkyl having 2 to 8 carbon atoms, secondary alkyl and secondary hydroxyalkyl radicals having 3 to 8 carbon atoms, tertiary alkyl and tertiary hydroxyalkyl radicals having 4 to 8 carbon atoms, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6 and R.sub.7 are each independently selected from the group consisting of hydrogen, C.sub.1 -C.sub.3 alkyl and hydroxyalkyl radicals, with the proviso that R.sub.2, R.sub.3, R.sub.6, and R.sub.7 are C.sub.1 -C.sub.4 alkyl or hydroxyalkyl radicals when R.sub.1 and R.sub.8 are primary alkyl or hydroxyalkyl radicals, and at least one of R.sub.2 or R.sub.3 and R.sub.6 or R.sub.7 are C.sub.1 to C.sub.3 alkyl or hydroxyalkyl radicals when R.sub.1 and R.sub.

Abstract: A process for removing acid gases such as CO.sub.2 and H.sub.2 S from gas streams using a cyclic aqueous alkaline scrubbing solution which is circulated between an absorption and regeneration stage is disclosed. This process is improved by integrating within this cyclic system a process scheme wherein condensed steam having gaseous impurities dissolved therein is recovered from the feed gas and subjected to a pressure below which scrubbing solution regeneration takes place. While maintaining this pressure, the process condensate is heated, boiled and stripped to evolve a vaporous mixture comprising steam and gaseous impurities which are compressed and introduced into the regeneration stage. By this process, useful work is performed by low temperature process streams thereby improving the overall efficiency of the cyclic process.

Abstract: The present invention relates to a process for the selective extraction treatment of a gaseous hydrocarbon mixture containing 5 to 3000 ppm (parts per million) by volume of hydrogen sulfide and 0.3 to 3% carbon dioxide, in order to obtain a purified gas containing less than 4 ppm by volume hydrogen sulfide and less than 2% carbon dioxide.The gaseous hydrocarbon mixture is submitted to a series of counter-current washings by contact with a tertiary amine aqueous solution in an absorption zone from which is drawn a liquid effluent enriched in hydrogen sulfide.

Abstract: A gas stream containing CO.sub.2 and H.sub.2 S is contacted with an alkanolamine in a contacting zone. The rich solution is then selectively stripped in a stripping zone to produce a gas stream containing a higher CO.sub.2 :H.sub.2 S mole ratio than the initial stream. This stream can be recycled to the alkanolamine contacting zone. The partially stripped solution can be introduced into another stripping zone to provide a third gas stream which is rich in H.sub.2 S and lean in CO.sub.2 suitable as feed for a Claus Unit and a lean alkanolamine solution which can be recycled to the contacting zone.