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1.
公开(公告)号:US5095135A
公开(公告)日:1992-03-10
申请号:US680502
申请日:1991-04-04
申请人: Teruaki Yamada , Kazuhiko Maeda , Ryohei Minami , Yukio Nagao , Kazuki Sugiura
发明人: Teruaki Yamada , Kazuhiko Maeda , Ryohei Minami , Yukio Nagao , Kazuki Sugiura
IPC分类号: C07C51/265 , C07C67/52
CPC分类号: C07C51/265 , C07C67/52
摘要: A process for the preparation of naphthalenecarboxylic acid esters in which a substituted naphthalene is oxidized with molecular oxygen in the presence of a heavy metal-based catalyst in a solvent comprising a lower aliphatic monocarboxylic acid to form a naphthalenecarboxylic acid and the resulting acid is then esterified. The esterified product is purified by washing, recrystallization, and distillation in that order. Heavy metals are recovered as carbonates from filtrates and washings obtained by seeparation of crude acid and ester products and by washing thereof.
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公开(公告)号:US4925977A
公开(公告)日:1990-05-15
申请号:US284678
申请日:1988-12-15
申请人: Teruaki Yamada , Yoshiji Doko , Kazuki Sugiura
发明人: Teruaki Yamada , Yoshiji Doko , Kazuki Sugiura
IPC分类号: B01J27/08 , B01J27/128 , C07B61/00 , C07C51/00 , C07C51/265 , C07C63/38 , C07C67/00
CPC分类号: C07C51/265
摘要: An improved method for the preparation of a naphthalene dicarboxylic acid by liquid-phase catalytic oxidation of a diisopropylnaphthalene in a lower fatty acid-based solvent is disclosed wherein a catalyst system comprising bromine and the heavy metals cerium, cobalt, and manganese is used. The cerium compound used as a cerium source for the catalyst can be recovered from crystals of the naphthalene dicarboxylic acid product by dissolving the crystals in an alkali solution and separating the cerium compound as insolubles from the solution.
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