Product recovery
AssigneeE. I. Du Pont de Nemours and Company
InventorJohn William Corn
Life of this patent
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Abstract
Process for the recovery of reactants and products from a catalyst containing residue, e.g., a residue obtained from the hydrocyanation of olefins such as butadiene using a zero-valent nickel complex as the hydrocyanation catalyst wherein the complex is promoted with a triarylborane or a zinc compound such as zinc chloride. The residue is mixed, i.e., extracted with a solvent consisting essentially of monoolefinically unsaturated nitriles, e.g., 3-pentenenitrile. The resulting extract containing the pentenenitriles and the desired products, e.g., adiponitrile and its precursors is separated from the insoluble materials consisting essentially of catalyst residue and at least a portion thereof is returned to the hydrocyanation process.
Claims4
An process for the recovery of organic nitriles from a waste stream containing products, by-products and catalyst residue obtained from a process for the production of adiponitrile by the hydrocyanation of butadiene in the presence of a zero-valent nickel catalyst wherein said waste stream is obtained after recovery of product from the hydrocyanation reaction which process comprises extracting said waste stream with an extractant consisting essentially of organic nitriles having about 5-10 carbon atoms and having a boiling point below about 250.degree. C at atmospheric pressure, separating the resultant extract from the insoluble material at a temperature below about 215.degree. C and thereafter returning at least a portion of the extract to the hydrocyanation process.
Dependencies are inferred from the claim text.