SEPARATION AND PURIFICATION OF 2,6-DIISOPROYLNAPHTHALENE

PURPOSE:To easily obtain high-purity 2,6-diisopropylnaphthalene in high yield by putting to separation and purification a feedstock mixture of 2,6- diisopropylnaphthalene and 2,7-diisopropylnaphthalene using a cooling crystallization method with a specific equipment. CONSTITUTION:The first crystallizer 1 is fed with a feedstock mixture in the form of a solution comprising 2,6-diisopropylnaphthalene (DIPN) and 2,7-DIPN via a piping 10 to carry out crystallization to produce a crystal-containing slurry, which is, in turn, fed to a filter press 3 where a press squeezing is made at >=50atm (pref. 80-300atm) to effect solid-liquid separation to produce a crude crystal containing >=90wt.% of 2,6-DIPN. A feedstock solution for purification is then prepared by dissolving this crude crystal in a solvent, and crystallized in the second crystallizer 2 to produce a 2,6-DIPN-contg. crystal slurry, which is, in turn, put to solid-liquid separation using a centrifugal separator 4, thus obtaining the objective compound containing >=99wt.% of 2,6-DIPN.