| 摘要 |
<p>PURPOSE:To obtain the 2,6-isomer useful as an intermediate for the production of naphthalenedicarboxylic acid, etc., by the liquid-phase catalytic isomerization of dimethylnaphthalene in the presence of a zeolite wherein the opening of its main cavity is made of a 10-membered oxygen ring. CONSTITUTION:The 2,6-isomer of dimethylnaphthalene is produced by isomerizing a dimethylnaphthalene fraction, etc. separated from the recycling oil of the FCC process, at 300-400 deg.C under a pressure sufficient to liquefy the fed raw material, in the presence of a zeolite wherein the opening of its main cavity is made of a 10-membered oxygen ring. The zeolite is an acid-type aluminosilicate having a pentasil structure, and the molar ratio of SiO2/Fe2O3 is 12-100. It can be used singly or as a formed product in combination with other assistants such as silica, alumina, etc. The above isomerization reaction enables the isomerization of an isomer which is hardly isomerizable by conventional method.</p> |
