Abstract: A method and apparatus for sequestering entrained or volatile catalyst species in a carbonylation process includes contacting the product stream with a vinyl pyridine or a vinyl pyrrolidone resin bed which is operative to sequester entrained or volatile catalytic species. The invention is particularly useful in connection with the iridium catalyzed carbonylation of methanol wherein the loss of entrained or volatile catalyst species depletes the catalytic content of the reactor. The resin may be digested in order to recover the catalytic metals.

Abstract: The present invention is directed to using methyl acetate from a vinyl acetate-based or a vinyl-or ethylene-alcohol based polymer or copolymer process directly for use in a methanol carbonylation production process to produce acetic acid, acetic anhydride, or a coproduction of each.

Abstract: A low energy process for producing acetic acid by the carbonylation of methanol is disclosed. The process involves a rhodium-catalyzed system operated at less than about 14% water utilizing up to 2 distillation columns. The process is preferably controlled such that the product stream has a low level of propionic acid impurity and the level of aldehyde impurities is minimized by way of aldehyde removal or minimizing aldehyde generation. The level of iodides is controlled by contacting the product, at elevated temperatures, with ion exchange resins. In preferred embodiments, at least one silver or mercury exchanged macroreticular strong acid ion exchange resin is used to purify the product. The high temperature treatment provides the added benefit of controlling the Color Value (Pt—Co units) of the product stream.

Abstract: The method of the present invention provides an improvement upon prior art methanol carbonylation methods which substantially reduces the production of carbonyl impurities. The production of carbonyl impurities, particularly acetaldehyde, crotonaldehyde, and 2-ethyl crotonaldehyde, in methanol carbonylation reactions has been found to decrease by maintaining less than about 4.5 wt % methyl iodide in the reaction medium during the course of the reaction.

Abstract: The method of the present invention provides an improvement upon prior art methanol carbonylation methods which substantially reduces the production of carbonyl impurities. The production of carbonyl impurities, particularly acetaldehyde, crotonaldehyde, and 2-ethyl crotonaldehyde, in methanol carbonylation reactions has been found to decrease by maintaining a partial pressure of hydrogen between about 0.1 and 4 psia at reaction total pressure of from about 15 to about 40 atmospheres total reaction pressure.

Abstract: A process for inhibiting free-radical polymerization of an alpha,beta-unsaturated (&agr;,&bgr;-unsaturated) carboxylic acid, and for providing desired grade &agr;,&bgr;-unsaturated carboxylic acid for use following storage and transport is described herein. In particular, bulk storage and shipment such as with overseas transport is described. The process comprises combining the &agr;,&bgr;-unsaturated carboxylic acid with a phenolic inhibitor and a coinhibitor to form an inhibited mixture, storing the inhibited mixture, transporting the inhibited mixture, and removing the coinhibitor to provide the desired grade &agr;,&bgr;-unsaturated carboxylic acid for use. In preferred embodiments, the &agr;,&bgr;-unsaturated carboxylic acid is acrylic acid, the phenolic inhibitor is p-methoxyphenol, the coinhibitor is manganese cation, and removal of the coinhibitor is carried out using an ion exchange resin.

Abstract: Disclosed is a method to manufacture high purity acetic acid. Although described in relation to that produced by a low water carbonylation process the present invention is applicable to other mechanisms for production of acetic acid which results in formation of permanganate reducing compounds such as acetaldehyde, propionic acid, and alkyl iodide impurities in intermediate process streams. It has been found that permanganate reducing compounds and alkyl iodides may be conveniently removed from a light phase of an intermediate stream in the reaction process by employing a multiple distillation process coupled with an optional extraction of acetaldehyde. The distillation process involves first distilling a light phase to concentrate the permanganate reducing compounds, and in particular the acetaldehyde, and then separating the permanganate reducing compounds and alkyl iodides in a second distillation tower.

Abstract: A process to reduce carbonyl impurities in a carbonylation reaction for the production of acetic acid is described. The methyl iodide recycle stream which is directed to a carbonylation reactor for carbonylating methanol or methyl acetate to acetic acid, is treated to remove carbonyl impurities by reacting the methyl iodide stream formed in the reaction with an aqueous amino compound which reacts with the carbonyls to form water soluble nitrogenous derivatives, separating an organic methyl iodide phase from an aqueous derivative phase and distilling the methyl iodide phase to remove heavier impurities. The treatment of the methyl iodide recycle stream to the carbonylation reactor has been found to greatly reduce the carbonyls present in the acetic acid product. The formation of nitrile from the nitrogenous derivative during distillation may be minimized by adding water to the system.

Abstract: A method is provided to improve the quality of recycle of certain residues by modifying the separation of alkanes and alkane-like materials and carbonyl-containing impurities from the recycle during the manufacture of acetic acid by the carbonylation of methanol. The improvement comprises partitioning the residues by the addition of water obtained from aqueous streams containing up to 50 wt. % acetic acid and which have been treated in a catalytic distillation unit to react the acetic acid with methanol to form recyclable methyl acetate and water and wherein the water is separated from the organics by distillation.

Abstract: A carbonylation catalyst useful for the carbonylation of methanol to acetic acid, acetic anhydride or both comprises a polymer support containing pendant pyrrolidone groups which support a rhodium species. Other polymeric supports capable of withstanding carbonylation temperatures of at least 150.degree. C. are disclosed for the carbonylation reaction in which rhodium levels in the reaction medium of greater than 500 ppm are contemplated.

Abstract: A method is provided to improve the quality of recycle of certain residues by modifying the separation of alkanes and alkane-like materials and carbonyl-containing impurities from the recycle during the manufacture of acetic acid by the carbonylation of methanol. The improvement comprises operating a prior art stripper column in a reflux manner and partitioning the residue therefrom by the addition of water. The method also reduces the volume of disposal of potentially valuable recyclable reactants.

Abstract: A method is provided for removing iodide compounds, particularly alkyl iodide compounds, from iodine-containing liquids, particularly carboxylic acids and anhydrides manufactured by the carbonylation of alcohols, ethers, esters, and the like in the presence of a rhodium catalyst and an alkali metal or alkaline earth metal salt, particularly a lithium salt, wherein the carboxylic acid or anhydride is contacted with a silver or mercury salt coordinated to a polymeric resin containing functional groups having the capability to quaternize with or form ionic salts with the alkyl halides.

Abstract: A carbonylation catalyst useful for the carbonylation of methanol to acetic acid, acetic anhydride or both comprises a polymer support containing pendant pyrrolidone groups which support a rhodium species. Other polymeric supports capable of withstanding carbonylation temperatures of at least 150.degree. C. are disclosed for the carbonylation reaction in which rhodium levels in the reaction medium of greater than 500 ppm are contemplated.

Abstract: Esters such as methyl acetate which contain carbonyl impurities including aldehydes are purified by adding to the esters an amino compound which reacts with the carbonyls to form water soluble nitrogenous derivatives, separating an organic ester phase from an aqueous derivative phase, and distilling the ester phase to further remove heavier impurities. The formation of nitrile from the nitrogenous derivative is minimized by adding water to the distillation column or washing the aqueous bottoms from distillation with water to further remove the derivatives from any ester contained in the bottoms. The organic phase recovered from the bottoms can be recycled to the distillation to recover ester.

Abstract: Acetic acid produced by the low water carbonylation of methanol and containing iodide, unsaturates and carbonyl impurities is purified by treatment with ozone.

Abstract: Acetic acid containing iodide, unsaturates and carbonyl impurities is purified by treatment with ozone and thereafter contacted with activated carbon and/or an ion-exchange resin for removal of impurities.

Abstract: Acetic acid containing iodide, unsaturates and carbonyl impurities is purified by treatment with ozone in the presence of an oxidation catalyst. The acetic acid product may be further contacted with activated carbon or ion-exchange resins for additional removal of impurities.

Abstract: A process for treating carbonylation catalyst solutions which contain a rhodium component and a lithium component to remove metallic corrosion products comprises contacting the catalyst solution with a cation exchange resin in the lithium form.

Abstract: This invention describes an improved process for the production of C.sub.1 -C.sub.8 alkyl acrylate by the reaction of a C.sub.1 -C.sub.8 alkyl alcohol with acrylic acid in the presence of esterification catalysts and soluble manganese or cerium ions.

Abstract: New and improved compositions are described of ethylenically unsaturated organic compounds capable of addition polymerization stabilized from unintentional or premature polymerization in the liquid phase by the addition of the combination cerium compounds which are soluble in the ethylenically unsaturated organic compounds and phenolic type inhibitors.