Process for the purification of halo-aldehydes
AssigneeSocieta' Italiana Resine S.I.R. S.p.A.
InventorsJacob Ackermann, Pierino Radici
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Abstract
Purification of haloaldehydes in a process that consists essentially of a first stage of purification in which the haloaldehydes are brought into contact with an absorbent solid, basic in nature, in the presence of water or free alcohols, and of a second stage of purification in which the halo-aldehydes thus treated are brought into contact with a solid absorbent carrying sulphonic, phosphonic or carboxylic acid groups in the form of salts of alkali or alkaline earth metals.
Claims13
A process for the purification of halo-aldehydes selected from the group consisting of monochloroacetaldehyde, dichloroacetaldehyde, trichloroacetaldehyde, monofluoroacetaldehyde, difluoroacetaldehyde, trifluoroacetaldehyde, bromoacetaldehyde and alpha-alpha-beta-trichloro-n-butyraldehyde, wherein in conducting a first stage of purification the said halo-aldehydes, in liquid form, are brought into contact with an absorbent solid consisting of an anionic exchange resin consisting of a polystyrene exchange resin having quaternary ammonium groups bonded thereto, said first stage being carried out in the presence of a free alcohol selected from the group consisting of methanol and ethanol or water in quantities of 0.15 to 5.0% by weight with respect to the halo-aldehydes, and conducting a second stage of purification wherein said halo-aldehyde, thus treated and in liquid form, is brought into contact with an absorbent solid consisting of a cationic exchange resin consisting of a polystyrene exchange resin having sulfonic groups linked thereto and in the form of salts of alkali or alkaline earth metals, said process being carried out at a temperature from the melting temperature to the boiling temperature of said halo-aldehyde.
Dependencies are inferred from the claim text.