Abstract: A process is provided for removing solid and liquid impurities from a particulate arylene sulfide polymer recovered from a polymerization reaction mixture slurry, without significantly discoloring the resulting washed polymer. The process of this invention comprises the steps of: (a) preparing a first slurry, wherein the solid component thereof comprises a particulate arylene sulfide polymer recovered from a reaction mixture slurry, and wherein the liquid component thereof comprises a mixture of water and a reducing agent; (b) heating the first slurry to a temperature of at least about 185.degree. C. (365.degree. F.) but below the melting point of the particulate polymer, to wash the polymer contained therein; (c) cooling the first slurry to a temperature below about 100.degree. C. (212.degree. F.), to form a second slurry, wherein the solid component thereof comprises a washed particulate arylene sulfide polymer; and (d) recovering the washed particulate arylene sulfide polymer from the second slurry.

Abstract: Virgin poly(arylene sulfide) resins are oxidatively cured by heat treatment at an elevated temperature below the melting point of the resin, under an oxidizing atmosphere comprising less than a 20 volume % oxygen concentration. The resulting polymer exhibits drastically improved thermal stability with no apparent sacrifice in physical properties.

Abstract: A method for controlling the filling status of particulate solids in a solids container is provided using an apparatus comprising an empty/full indication device comprising a conduit structure, having a vertically opened upper end and a vertically opened lower end, wherein the vertically opened upper end is in open communication with the upper end portion of the solids container at the location of a predetermined full level and the vertically opened lower is in open communication with the lower end portion of the solids container at the location of a predetermined empty level.

Abstract: In one embodiment, a process is provided for treating virgin poly(arylene sulfide) resins, wherein a heated polymer slurry, comprising a virgin poly(arylene sulfide) resin and water is contacted by an acidic treating solution comprising at least an acidic component, wherein the amount of the acidic component in the acidic treating solution is less than the amount necessary to result in at least a partial curing of the virgin poly(arylene sulfide) resin. In a second embodiment, the process is provided for treating a virgin poly(arylene sulfide) resin, wherein the virgin poly(arylene sulfide) resin is slurried with an aqueous acidic treating solution comprising an acidic component and an aqueous component and the concentration of the acidic component in the aqueous acidic treating solution is less than the amount necessary to result in at least a partial curing of the virgin poly(arylene sulfide) resin.

Abstract: Poly(arylene sulfide) oligomers are recovered in a process comprising steps of:(a) dehydration of an aqueous admixture of alkali metal hydroxide such as sodium hydroxide, and alkali metal bisulfide such as sodium bisulfide, in a polar organic solvent such as N-methyl-2-pyrrolidone (NMP), wherein the molar ratio of alkali metal hydroxide to alkali metal bisulfide is about 0.90:1 to about 1.05:1 prior to dehydration and 0.99:1 to about 1.

Abstract: Method and apparatus for the separation of solid particulate polymer from liquid diluent comprising the use of one or more accumulator legs to which diluent is supplied, and separated diluent is recycled to the polymerization process.

Abstract: Improved process for the separation of a hydrocarbon-containing feedstream comprising monomer, comonomer and diluent into separate product streams which comprises subjecting the feedstream to two-stage distillation provided with a common accumulation zone wherein the condensate from the accumulation zone serves as the source of feed for the second distillation and reflux for the first distillation. In a specific embodiment, a feed comprising ethylene, 1-hexene, and isobutane is separated into separate streams of 1-hexene, ethylene and isobutane, and isobutane for recycle to polymerization.

Abstract: A process for producing alkali metal aminobutyrate or alkali metal aminobutyrate-alkali metal bisulfide complex by contacting an aqueous alkali metal hydroxide with NMP and optionally alkali metal bisulfide in a stirred reactor under reaction conditions to produce a predominantly one-phase system and maintaining these reaction conditions while passing the one-phase system through a disrupted flow tube reactor to complete the reaction. Dehydrating the reaction product in a two-stage dehydration process using a higher temperature in the second stage.

Abstract: Granular poly(arylene sulfide) is recovered from a slurry comprising granular poly(arylene sulfide), polar organic solvent, alkali metal halide, poly(arylene sulfide) oligomers, untreated reactants in the water by heating the slurry under conditions to evaporate polar organic solvent, water and volatile impurities at a temperature below the normal boiling point of the polar organic solvent to produce a dry mixture containing poly(arylene sulfide), poly(arylene sulfide) oligomers and alkali metal halide which is then reslurried with water to produce a reslurried mixture containing aqueous alkali metal halide solution and dispersed poly(arylene sulfide) oligomers with the reslurried mixture being filtered through a coarse screen to recover granular poly(arylene sulfide) thereon and pass a filtrate containing poly(arylene sulfide) oligomers and aqueous alkali metal halide solution therethrough.

Abstract: Phenol is extracted with a chlorinated aromatic extractant, such as p-dichlorobenzene, from an aqueous mixture containing phenol and N-methylpyrrolidone. In an embodiment of this invention the purified N-methylpyrrolidone is recycled for use in a poly(phenylene sulfide) polymerization process.

Abstract: A polymerization process wherein a slurry of polymer and diluent is passed from the polymerization zone to a flash zone, then polymer solids having residual diluent carried thereon are passed to a purge zone wherein a heated noncombustible gas is used to remove additional amounts of diluent, and then the vapor purge zone is condensed and cooled to produce a vapor stream comprising said noncombustible gas and a liquid stream comprising diluent.

Abstract: A method for producing a polymer in which lithium hydroxide, optionally also employing either lithium chloride or lithium acetate, is contacted with N-methyl-pyrrolidone in the presence of lithium halide to produce a reaction product mixture containing lithium N-methyl-4-aminobutyrate with this reaction mixture then being contacted with hydrogen sulfide and polyhalo aromatic compound in the presence of additional N-methyl-pyrrolidone under conditions to form a polymer. Lithium halide produced as a by-product is substantially recovered from the reaction mixture, converted to lithium hydroxide and can be recycled to the process.

Abstract: An improved polymerization process wherein vapors from a flash zone are condensed and used as wash liquid in a polymer washing zone and optionally a sidestream from a monomer fractionation zone is also used as wash liquid.

Abstract: A novel process is disclosed for separating liquid diluent from a slurry of the diluent and a solid polymer involving the use of a first intermediate pressure flash zone and a second lower pressure flash zone.

Abstract: Arylene sulfide polymers containing ash-forming impurities or materials are purified by contacting an aqueous mixture of such polymer with molecular oxygen under conditions sufficient to reduce the ash-forming impurities and concurrently at least partially cure the polymer.

Abstract: A method for dehydrating pre-polymerization mixtures in the preparation of poly(arylene sulfide) in which a reaction mixture of a sulfur source and an organic amide are contacted at a first pressure within a range of about 20 psig to about 60 psig and an initial temperature in a range of about 300.degree. F. to 400.degree. F. to form a complex of the reactants with the mixture subsequently subjected to a decrease in pressure while elevating the temperature to a second temperature at which, at the chosen pressure, essentially all water is removed from the mixture. Other compounds including bases, alkali metal carboxylates, alkali metal carbonates, lithium halides, and lithium borate can be present in the reaction mixture. Preferably the sulfur source is sodium sulfide and the organic amide is N-methylpyrrolidone.

Abstract: A method for removing carbonaceous impurity from zinc oxide by contacting a water slurry of contaminated zinc oxide with oxygen in a reactor at reaction conditions sufficient to produce oxide products of the carbon contaminants and passing the reactor effluent through a filter to collect solid zinc oxide while passing the oxides of carbon through the filter. In a preferred embodiment, contaminated zinc oxide separated from the reaction product in the preparation of terephthalic acid from benzoic acid using zinc benzoate catalyst is subjected to treatment for removal of carbonaceous contaminants before being recycled to reaction with molten benzoic acid to produce zinc benzoate catalyst used in the reaction.

Abstract: A process and apparatus for removing an impurity from a gas by means of selective absorption of a gas impurity by a suitable absorbent. The absorbent and gas are contacted in a contacting zone which is divided into a plurality of compartments with the absorbent and gas flowing cocurrently in each individual compartment. The overall system, however, is a countercurrent flow system wherein the absorbent flows downwardly and the gas flows upwardly. The process and the apparatus can be used for the removal of carbon dioxide from natural gas with the use of salt water as the absorbent. The invention is especially useful for a natural gas well located in offshore waters that produces a gas with a high concentration of carbon dioxide as the apparatus can be erected on the ocean floor and use the surrounding sea water as absorbent.

Abstract: Dimethyl formamide when used as an absorption solvent to remove acetylenes from olefin-containing gas streams acts as well as a promoter for the oxidative conversion of H.sub.2 S, COS, and/or CS.sub.2, also contained in the feed stream, to elemental sulfur. Thus both acetylenes and sulfur compounds are efficiently removed from such olefin-containing gas streams as coke oven gas. Further, the loss of dimethyl formamide entrained and vaporized by the deacetylenized gas stream leaving the dimethyl formamide absorber is substantially reduced or effectively eliminated by the injection of a stream of liquid selected from the group consisting of paraffinic hydrocarbons having 4-8 carbon atoms per molecule containing at least one tertiary carbon atom per molecule and aromatic hydrocarbons having 6-10 carbon atoms per molecule above the point of injection of the dimethyl formamide solvent stream to the absorption column.

Abstract: A process for treating a hydrocarbon composition containing both straight chain and non-straight chain hydrocarbons in which said hydrocarbon composition is separated into a straight chain hydrocarbon-rich fraction and a non-straight chain hydrocarbon-rich fraction, non-aromatics in said non-straight chain hydrocarbon-rich fraction are converted to aromatics, and at least a portion of the straight chain hydrocarbon-rich fraction is passed in combination with steam over a steam active catalyst comprising at least one Group VIII metal and a tin modified Group II metal aluminate under conditions such that aromatics are produced.