| 主权项 |
1. A method for producing a diaryl carbonate, using a metal-containing catalyst composition as a reaction catalyst, comprising:
a step (1) of subjecting a dialkyl carbonate and an aromatic monohydroxy compound to a transesterification reaction so as to obtain an alkylaryl carbonate, and removing an alcohol as by-product from a reaction system; a step (2) of subjecting the alkylaryl carbonate obtained in the step (1) to a transesterification or disproportionation reaction so as to obtain a reaction product including the diaryl carbonate; a step (3) of distilling the reaction product obtained in the step (2) to separate the reaction product into a low boiling component including the diaryl carbonate and a high boiling component including the reaction catalyst; and a step (4) of recycling the high boiling component separated in the step (3) into the steps (1) and/or (2),wherein:
the high boiling component separated in the step (3) includes 70% by mass or less of a component having a higher boiling point than that of the diaryl carbonate; the high boiling component separated in the step (3) includes a compound represented by the formula (1):wherein Ar1 represents an unsubstituted or substituted arylene group having 6 to 20 carbon atoms, X and Y—O are located at an ortho position to each other, X represents a hydroxy group or a substituent given by the formula (2) or (3), and Y represents hydrogen or a substituent given by the formula (3), the formulas (2) and (3) being as follows:wherein R1 represents a linear or branched aliphatic group having 1 to 12 carbon atoms, an alicyclic aliphatic group having 5 to 12 carbon atoms, or an unsubstituted or substituted aryl group having 6 to 20 carbon atoms; and
the high boiling component recycled in the step (4) includes compounds given by (i) to (iii): (i) a compound of the formula (1) where X represents the formula (2) or (3), and Y represents the formula (3); (ii) a compound of the formula (1) where X represents a hydroxy group, and Y represents the formula (3), and/or a compound of the formula (1) where X represents the formula (3), and Y represents hydrogen; (iii) a compound of the formula (1) where X represents a hydroxy group, and Y represents hydrogen; the compounds of (i) to (iii) satisfying conditions given by (iv) to (vi), respectively: (iv) total moles of the compounds of (i)/moles of metal atoms is 0.005 to 20; (v) total moles of the compounds of (ii)/moles of metal atoms is 0.005 to 4; and (vi) moles of the compound of (iii)/moles of metal atoms is less than 2. |
