Recovery of 2,6-dialkyl-naphthalene isomers
AssigneeRutgerswerke Aktiengesellschaft
InventorsWilhelm Holtmann, Robert Zellerhoff, Rudolf Oberkobusch, Peter Staglich, Bernhard Charpey
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Abstract
In a process for selective crystallization of 2,6-dialkyl-naphthalene selected from the group consisting of methyl-n-propyl-naphthalene, methyl isopropyl-naphthalene, ethyl-isopropyl-napthalene, ethyl-n-butyl-naphthalene, di-n-propyl-naphthalene, diisopropyl-naphthalene, methyl-amyl-naphthalene, ethyl-amyl-naphthalene, propyl-amyl-naphthalene, di-n-butyl-naphthalene and diisobutyl-naphthalene from their isomer mixtures from a polar solvent solution, the improvement comprising effecting the crystallization with constant stirring at a temperature from 25.degree. to -30.degree. C. to obtain the 2,6-dialkyl-naphthalene at least 95% pure.
Claims8
In a process for selective crystallization of 2,6-dialkyl-naphthalenes selected from the group consisting of methyl-n-propyl-naphthalene, methyl-isopropyl-naphthalene, methyl-n-butyl-naphthalene, methyl-isobutyl-naphthalene, ethyl-isopropyl-naphthalene, ethyl-n-butyl-naphthalene, di-n-propyl-naphthalene, diisopropyl-naphthalene, di-n-butyl-naphthalene and diisobutyl-naphthalene from their isomeric mixtures from a polar solvent solution at a temperature of 25.degree. to -30.degree. C., the improvement comprising effecting the crystallization with constant stirring to obtain the 2,6-dialkyl naphthalene in a high degree of purity.
Dependencies are inferred from the claim text.