Abstract: A process for adsorbing sulfur dioxide from a gas comprising contacting a gas containing SO.sub.2, such as a flue gas, with about stoichiometric amounts of a specially prepared calcium oxide so that substantially all of the sulfur dioxide content is reacted throughout the calcium oxide particle to form a calcium sulfate reaction product. The useful calcium oxide particles comprise a highly voided skeletal structure of very large surface area and large pore volume with numerous macro pores. Such particles are obtained by flash calcining sand-size grains of calcium carbonate, such as aragonite, calcite or dolomite.

Abstract: The invention disclosed is a novel method of making an improved carbon dioxide absorbing material. A primary carbon dioxide absorbent is employed, specifically a group IA and IIA metal hydroxide, and various combinations of additives which modify the properties of the primary absorbent, in the form of an aqueous solution, and sprayed onto the surface of the primary absorbent.

Abstract: The present invention relates to an alkaline promoter system comprising specific mixtures of nonsterically hindered amino compounds and sterically hindered amino acids and their use in acid gas scrubbing processes. The preferred promoter system comprises a mixture of (i) diethanol amine or 1,6-hexanediamine and (ii) N-secondary butyl glycine or pipecolinic acid.

Abstract: The present invention relates to an alkaline salt promoter system which includes N-secondary butyl glycine and its use in acid gas scrubbing processes.

Abstract: The present invention relates to an alkaline salt promoter system comprising specific mixtures of sterically hindered monosubstituted alpha-amino acids and tertiary amino acids and its use in acid gas scrubbing processes. The preferred promoter system comprises a mixture of N-secondary butyl glycine and N-methyl-N-secondary butyl glycine.

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 tertiary amino azabicyclic alcohol 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 severely sterically hindered secondary aminoether alcohol having a cumulative .sup.- -E.sub.s value (Taft's steric hindrance constant) greater than about 1.75 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 severely sterically hindered secondary amino compound having a cumulative .sup.- E.sub.s value (Taft's steric hindrance constant) greater than about 1.75 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 diaminoether wherein at least one amino group is a tertiary amine 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 di-secondary aminoether wherein each amino group has a severely sterically hindered secondary amino moiety whereby H.sub.2 S is selectively absorbed from the mixture.

Abstract: The present invention relates to an alkaline salt promoter system comprising specific mixtures of lower aliphatic mono-substituted alpha amino acids and sterically hindered diamino or triamino compounds and their use in acid gas scrubbing processes. The preferred promoter system comprises a mixture of N-secondary butyl glycine and N-cyclohexyl-1,3-propanediamine or N-cyclohexyl-1, 4-butanediamine.

Abstract: By separating a noxious-component-containing flue gas into two separate streams, subjecting one of these streams to dry purification and the other to wet purification, and recombining the resulting purified streams, purified flue gas is obtained at a temperature greater than the dew point of remaining corrosive constituents. This makes it possible to disseminate the recombined product through pipes and chimneys without a deleterious effect thereon.The beneficial results are obtained without having to heat the recombined gas stream even though the wet-purification process yields purified gas at a temperature far below that which is desired.Both the dry- and the wet-purification processes are significantly enhanced by incorporating piperazine in treating materials. Sorption agents used in the dry purification are reused in the wet purification, enhancing the efficiency of the disclosed system.

Abstract: Acidic gases containing carbon dioxide are removed from a normally gaseous mixture by absorbing CO.sub.2 from the gaseous mixture with an aqueous solution comprising a basic alkali metal salt or hydroxide and an activator or promoter system for the salt or hydroxide which contains (i) at least one diaminoalcohol of the formula:H.sub.2 N--(CH.sub.2).sub.4 --NRR'wherein R and R' each independently represent a C.sub.1 -C.sub.6 alkyl group and either R or R' or both R and R' have a pendant hydroxyl group, and (ii) an amino acid, and desorbing at least partially the absorbed CO.sub.2 from the aqueous solution.

Abstract: Acidic gases containing carbon dioxide are removed from a normally gaseous mixture by absorbing CO.sub.2 from the gaseous mixture with an aqueous solution comprising a basic alkali metal salt or hydroxide and an activator or promoter system for the salt or hydroxide which contains (i) at least one non-sterically hindered diamine defined as having both a primary and a tertiary amino moiety wherein the primary amino moiety is attached to a primary carbon atom, and (ii) an amino acid, and desorbing at least partially the absorbed CO.sub.2 from the aqueous solution.

Abstract: The corrosion of iron and steel surfaces by an aqueous alkanolamine conditioning solution used to remove CO.sub.2 from a gas stream is effectively inhibited by a combination of a vanadium containing ion and a soluble cobalt salt. This system allows the use of higher amine concentrations which in turn allows a higher carbon dioxide loading with low corrosion thereby improving the energy efficiency of the gas sweetening process.

Abstract: Novel amide acetals of the formula ##STR1## wherein R.sub.1 is hydrogen, methyl or Y and Y is the remnant of a hydroxyl-containing compound are claimed. The compounds are useful as water scavengers in fluid compositions.

Abstract: A composition comprising water, food compatible acid and porous rhyolite carrier, and a method of treating used fryer cooking oil are disclosed.

Abstract: The foam in acid gas scrubbing solutions created during an acid gas scrubbing process is reduced or eliminated by the addition of certain polyoxyethylene polyoxypropylene block cpolymers as defoaming agents. The defoaming agents are particularly effective when the acid gas scrubbing solution contains an amine having a large hydrophobic moiety.

Abstract: Antifoaming agents for use in acid gas scrubbing processes comprising 1-secondary or 1-tertiary alkyl- or 1-cycloalkyl-hexahydro-2-pyrimidinones and 1-secondary or 1-tertiary alkyl- or 1-cycloalkyl-2-imidazolidinones are disclosed.

Abstract: A method for removing compounds with offensive odor from an exhaust gas containing the same with a deodorant comprising a mixture of spherical particles of activated carbon and spherical particles of porous carbon impregnated with phosphoric acid or ammonium phosphate placed in a fluidized-bed type deodorizing unit.

Abstract: Cement waste product (CWP), such as recovered from kilns utilized in cement production, is used for scrubbing of sulfur oxide-containing industrial offgases. The CWP is preconditioned with liquid water prior to employing it as a scrubbing medium. Preconditioning involves addition of sufficient water to the essentially anhydrous CWP to achieve essentially total rehydration of the rehydratable calcium compounds contained in the CWP, for example, aluminates, oxide and sulfates. The preconditioned CWP is dried and used as a highly efficient scrubbing medium for sulfur oxides.

Abstract: This invention relates to a process for reducing the hydrogen cyanide content of a gaseous stream which comprises providing an adsorbent bed wherein the adsorbent comprises zinc oxide and contains no more than 5%, by weight, of an oxide of an alkali or alkaline earth metal, and contacting said process stream with said adsorbent bed at a temperature of from about ambient to about 350.degree. C. for a period of time sufficient to reduce the concentration of hydrogen cyanide in said gaseous stream to the desired value.

Abstract: Acidic gases are substantially removed from a normally gaseous mixture by a process comprising contacting the normally gaseous mixture with an amine-solvent liquid absorbent comprising (i) an amine comprised of at least about 50 mol % of a sterically hindered amine, and (ii) a solvent for said amine mixture which is also a physical absorbent for said acidic gases. The liquid absorbent may also include up to about 35 weight percent water.

Abstract: An improved process for the separation of sulfur oxides from a gaseous mixture containing sulfur oxides and oxygen is disclosed. The gaseous mixture is contacted with a solid sulfur oxide acceptor comprising copper, copper oxide, or a mixture thereof dispersed on a carrier material in combination with a platinum group metal component and a component selected from the group consisting of rhenium, germanium and tin.

Abstract: Acidic gases are substantially removed from a normally gaseous mixture by a process comprising contacting the normally gaseous mixture with an amine-solvent liquid absorbent comprising (i) an amine mixture comprised of at least about 50 mol % of a sterically hindered amine and at least about 10 mol % of a tertiary amino alcohol, wherein said sterically hindered amine contains at least one secondary amino group which is part of a ring and is attached to either a secondary or tertiary carbon atom or a primary amino group attached to a tertiary carbon atom, and (ii) a solvent for said amine mixture which is also a physical absorbent for said acidic gases. The liquid absorbent may also include up to about 35 weight percent water. The coaction of the sterically hindered amine and the tertiary amino alcohol in conjunction with the solvent provides an increase in the amount of CO.sub.2 containing acidic gases absorbed compared to the use of the same sterically hindered amines alone and lowers the heat of reaction.

Abstract: A reagent for treating flue gases constituted by an intimate mixture, in the solid state, of a main component selected from the group comprising alkaline-earth, oxides, hydroxides, carbonates, bicarbonates, and mixtures thereof, and an additive selected from the group comprising hydrogen halide acids, salts of such acids of alkaline metals, ammonium, and alkaline-earth metals, sulphuric acid, and mixtures thereof, said additive being present in an amount of from 0.1 to 15% by mole respect to said main component.

Abstract: Acidic components are removed from gaseous mixtures by contacting the gaseous mixture with an aqueous solution comprising (1) a basic salt and (2) an activator for said basic salt comprising at least one sterically hindered amine and an aminoacid which is a cosolvent for the sterically hindered amines. The aminoacid serves to prevent phase separation of the aqueous solution at high temperatures and low fractional conversions during the contacting.

Abstract: Carbon dioxide containing acidic gases are substantially removed from a normally gaseous mixture by a process comprising contacting the normally gaseous mixture with an aqueous amine solution, wherein the amine consists of at least about 50 mol % of a sterically hindered amino alcohol and at least about 10 mol % of a tertiary amino alcohol, wherein said sterically hindered amino alcohol contains at least one secondary amino group which is part of a ring and is attached to either a secondary or tertiary carbon atom or a primary amino group attached to a tertiary carbon atom. The coaction of the sterically hindered amino alcohol and the tertiary amino alcohol provide an increase in the amount of carbon dioxide containing acidic gases absorbed compared to the use of the sterically hindered amines alone and lowers the heat of reaction.

Abstract: Carbon dioxide containing acidic gases are removed from a normally gaseous mixture by a process comprising contacting the normally gaseous mixture with an aqueous solution comprising (a) a basic alkali metal salt or hydroxide and (b) an activator for said basic salt or alkali metal salt or hydroxide comprising at least one sterically hindered amine.

Abstract: A waste gas containing sulfur oxides is contacted with an adsorbent comprising an intimate mixture of an iron oxide and/or a copper oxide and a titanium oxide at a temperature of 250.degree.-500.degree. C. The sulfur oxides thus adsorbed are desorbed with a reducing gas and recovered as sulfur material.The efficiency of the adsorbent is not reduced even after many repetitions of the adsorption-desorption cycle. Since the adsorbent exhibits a high resistance to sulfuric acid mist (SO.sub.3) contained in the waste gas.

Abstract: A method is disclosed for producing attrition-resistant particles of dolomite or limestone by partially glazing the exterior of the particles with a suitable glaze-forming flux, the resulting composition being useful for removing sulfur dioxide from a combustion gas using the attrition-resistant particles.

Abstract: Process for preparing shaped base materials for use in solid catalysts for commercial processes. The solid contact material is prepared by pre-soaking a porous solid particulate carrier material in an organic liquid, immersing the carrier without drying in a dilute acid solution for a given time interval, washing, drying and calcining the impregnated carrier. After calcination, the carrier is impregnated with an active material.

Abstract: A spill of liquid caustic is controlled and cleaned up by being neutralized and absorbed into a novel granular composition formed from citric acid, expanded perlite, flour, fumed silica, a pH indicator dye and water.

Abstract: A method is disclosed for treating an aqueous medium containing magnesium sulfite tri-hydrate under precipitating conditions comprising adding in combination to the aqueous medium an effective amount for the purpose of an oligomer and a copolymer of a 1-olefin and an unsaturated anhydride.

Abstract: Alkali metal or alkaline earth metal oxides are impregnated within refractory support material such as alumina and introduced into a fluidized-bed process for the combustion of coal. Sulfur dioxide produced during combustion reacts with the metal oxide to form metal sulfates within the porous support material. The support material is removed from the process and the metal sulfate regenerated to metal oxide by chemical reduction. Suitable pore sizes are originally developed within the support material by heat-treating to accommodate both the sulfation and regeneration while still maintaining good particle strength.

Abstract: A pourable solid filter material for the removal of foreign gases, particularly unpleasant odors, from the air comprises a granular composition. The granular composition is a mixture of at least one acid or basic chemosorptive substance which reacts chemically with the foreign gas, and a substance which stores moisture. A binder which binds the chemosorptive substance into the form of granules is preferably also used as the moisture storing substance. The granules may consist of spherical particles between 0.5 to 5 mm. in diameter. Suitable acid chemosorpents include organic carboxylic acids, amidosulphonic acid, p-toluene sulphonic acid, boric acid, sodium, potassium and ammonium hydrogen sulphates and phthalic andydride. Preferred basic chemosorbents include sodium and potassium carbonates, oxides or hydroxides of calcium and barium, sodium metasilicate, lithium carbonate, hydroxides of sodium or potassium, cement, and potash, double, and soda water glass.

Abstract: This disclosure describes a process for the preparation of iron-bearing and calcium-bearing sorbent solids for use in the desulfurization of gases. The process involves mechanical procedures for generating porous agglomerated solids that are high in surface area and uniquely suitable in both particle size and mechanical properties for processing in gas-solids contacting equipment of conventional design. The process also involves the use of water in the agglomeration procedures in quantities controlled to react both chemically and mechanically with solid components of the feed materials and to generate adhesive cement between finely divided solids in porous agglomerated particles of the sorbent product.

Abstract: A stack gas, generally from a sulfuric acid plant, containing SO.sub.2, is contacted with an absorptive medium prepared by wetting at least the surface of a first metal selected from aluminum, magnesium and manganese with a second metal selected from mercury, indium, gallium and alloys of indium/gallium and contacting the wetted first metal with SO.sub.2, in a solvent medium in the presence of an excess of hydrogen ions until the first metal erodes and is taken up by the solution as a result of the reaction which takes place. The absorptive medium thus formed has the ability to absorb SO.sub.2 at lower temperatures and thereafter desorb SO.sub.2 at increased temperature and/or with inert gas stripping. The SO.sub.2 enriched gas stream obtained as a result of the desorption process can be recycled to the sulfuric acid plant.

Abstract: Sulfur dioxide is removed from gas mixtures such as flue gas containing the same by contacting the gas mixture with a solid sorbent comprising a porous gamma-alumina base, about 2 to 20 percent by weight (based on alumina) of a coating of a refractory oxide such as titanium dioxide, zirconium dioxide, or silica, and an active material, such as copper oxide, which is capable of selective removal of sulfur oxides from a gas mixture.

Abstract: When copper-containing acceptors for removal of sulfur oxides out of waste gases are being prepared by impregnating an alumina-containing carrier which has been calcined at a temperature above 780.degree.C with a solution containing cations of one or more of the metals aluminum, magnesium, titanium and/or zirconium either prior to or simultaneously with the impregnation with a solution containing copper cations, the capacity of the acceptor for sulfur oxides can be substantially increased by impregnating the carrier with a solution containing cations of one or more alkali metals either subsequent to or simultaneously with the impregnation employing the solution containing aluminum, magnesium, titanium and/or zirconium cations.