摘要:
A process for removing acetone from an acetone/methyl acetate/methyl iodide mixture utilizing extractive distillation with water being introduced to the distillation zone above the point of introduction of the mixture and acetic acid being introduced at or above the point of introduction of the mixture. In a preferred embodiment the mixture is subjected to an initial extraction with an aqueous extractant to remove most of the methyl iodide.The process is particularly applicable to removing acetone by-product in carbonylation processes for the production of acetic anhydride.
摘要:
A process is disclosed for removing palladium from a contaminated polyketone containing palladium which comprises contacting the contaminated polyketone with an olefin in the substantial absence of carbon monoxide at a temperature above the temperature at which the polyketone was formed and in a solvent in which the contaminated polyketone is insoluble. The process is preferably carried out in the presence of an acid. The temperature at which the process is carried out is preferably at least 20.degree. C. greater than the polymerization temperature.
摘要:
A continuous process for the dehydrogenation of a hydrocarbon and/or oxygenated hydrocarbon feed, comprising contacting the hydrocarbon and/or oxygenated hydrocarbon feed with a dehydrogenation catalyst at elevated temperature in a reaction zone characterized in that the catalyst is capable of retaining hydrogen and (a) is contacted with a feed to form a dehydrogenated product and hydrogen, at least some of the hydrogen formed being adsorbed by the catalyst and/or reacting therewith to reduce at least part of the catalyst; (b) the dehydrogenated product and any unadsorbed/unreacted hydrogen is removed from the reaction zone; (c) at least some of the adsorbed hydrogen is removed from the catalyst and/or at least some of the reduced catalyst is oxidized; and (d) reusing the catalyst from step (c) in step (a).
摘要:
In a process for the production of acetic acid by carbonylation of methanol in the presence of a rhodium carbonylation catalyst, methyl iodide and an iodide salt stabiliser the improvement resides in maintaining a finite concentration of water of up to about 10% by weight and a methyl acetate concentration of at least 2% by weight in the liquid reaction composition and recovering the acetic acid product by passing the liquid reaction composition through a flash zone to produce a vapour fraction which is passed to a single distillation column from which an acetic acid product is removed.
摘要:
A process for purifying an iodide-contaminated carboxylic acid and/or anhydride fraction obtained by liquid phase carbonylation using a carbonylation catalyst, an iodine-containing promoter and optional iodine-containing copromoter comprises vaporizing the fraction after it has been freed of catalyst, feedstock and promoter components to produce a vapor acid and/or anhydride fraction having reduced iodide contamination.