[EN] YIELD-EFFICIENT PROCESS FOR THE PRODUCTION OF HIGHLY PURE 2-METHYL-1,4-NAPHTHOQUINONE AND ITS DERIVATIVES<br/>[FR] PRODUCTION À FORT RENDEMENT DE 2-MÉTHYL-1,4-NAPHTOQUINONE D'UNE GRANDE PURETÉ ET DE SES DÉRIVÉS
申请人:LONZA AG
公开号:WO2011085945A1
公开(公告)日:2011-07-21
The present invention discloses a process for the production of 2-methyl-1,4-naphthoquinone and its bisulfite adducts, comprising the following steps: a) oxidizing 2-methyl-naphthalene (2-MNA) to achieve an organic phase containing 2-methyl-naphthoquinone (2-MNQ) and 6-methyl-naphthoquinone (6-MNQ); b) subjecting said organic phase to treatment with an aqueous solution of a bisulfite salt to extract preferentially the 6-MNQ isomer from the organic phase; c) separating said organic phase from the aqueous phase; d) subjecting the organic phase of process step c) to a second bisulfitation step with an aqueous solution of a bisulfite salt, resulting in an organic phase containing 2-MNA and trace amounts of 2-MNQ and an aqueous phase containing 2-MSB and trace amounts of 6-MSB; e) optionally removing interfering bisulfite ions from the aqueous phase of process step c); f) raising the pH of the aqueous phase from step c) or e) to higher than 8,5 in the presence of a solvent resulting in an organic phase containing 2-MNQ; g) combining the organic phase from step f) with the organic phase being treated in the process step d); h) recycling the organic phase from step d) back to step a) to be used as solvent for the oxidation reaction of 2-MNA.
Yield-efficient process for the production of highly pure 2-methyl-1,4-naphthoquinone and its derivatives
申请人:Lonza Ltd.
公开号:EP2345631A1
公开(公告)日:2011-07-20
The present invention concerns a process for the production of 2-methyl-1,4-naphthoquinone and its derivatives, comprising the following steps:
a) oxidizing 2-methyl-naphthalene (2-MNA) to achieve an organic phase containing 2-methyl-naphthoquinone (2-MNQ) and 6-methyl-naphthoquinone (6-MNQ);
b) subjecting said organic phase to treatment with an aqueous solution of a bisulfite salt to extract preferentially the 6-MNQ isomer from the organic phase;
c) separating said organic phase from the aqueous phase:
d) optionally removing interfering bisulfite ions from said aqueous phase
e) raising the pH of said aqueous phase to higher than 8.5 in the presence of a solvent resulting in an organic phase containing 2-MNQ;
f) isolating said 2-MNQ from said organic phase.