PURPOSE: To produce methylnaphthalene, by distilling a methylnaphthalene-containing hydrocarbon oil and a polyalkylene glycol to obtain the azeotropic fraction of methylnaphthalene and polyalkylene glycol, and leaving the fraction at rest at normal temperature to cause the separation into two layers.
CONSTITUTION: A methylnaphthalene-containing hydrocarbon oil (distillate obtained by the fractionation of coal tar or petroleum hydrocarbon oil) is distilled together with a polyalkylene glycol (e.g. diethylene glycol) to obtain an azeotropic fraction of methylnaphthalene and polyalkylene glycol. The fraction is left at rest at normal temperature to cause the separation into two layers, and methylnaphthalene is separated from the upper layer. The polyalkylene glycol existing in the lower layer can be recycled without particular purification treatment. When the phase-separation of the azeotropic mixture is carried out after the addition of a small amount of water, the dissolution of methylnaphthalene in the polyalkylene glycol can be prevented.
USE: Raw material of solvents, dyeing carrier, and heat medium.
KUBO KEIJI
TAKEYA SHIYOUJI
NAKAMURA TAKENORI
| JPS601142A | 1985-01-07 |
| GB668853A | 1952-03-26 |