Provided are a method for producing a terminal conjugated dienal compound without an oxidation reaction and a terminal hydroxyacetal compound useful as an intermediate in the method. More specifically, provided are a method for producing an (E)-dienal compound comprising the steps of: a metalation reaction of an alkynal acetal compound (1) to obtain an organic metal compound (2), an addition reaction of (2) to ethylene oxide to obtain a hydroxyalkynal acetal compound (3), a reduction reaction of (3) to obtain an (E)-hydroxyalkenal acetal compound (4), a functional group conversion reaction of (4) to obtain an (E)-alkenal acetal compound (5) having a leaving group X, an elimination reaction of (5) to obtain an (E)-dienal acetal compound (6), and a hydrolysis reaction of (6) to obtain the (E)-dienal compound (7); and others.

##STR00001##

Provided are a method for producing a terminal conjugated dienal compound without an oxidation reaction and a terminal hydroxyacetal compound useful as an intermediate in the method. More specifically, provided are a method for producing an (E)-dienal compound comprising the steps of: a metalation reaction of an alkynal acetal compound (1) to obtain an organic metal compound (2), an addition reaction of (2) to ethylene oxide to obtain a hydroxyalkynal acetal compound (3), a reduction reaction of (3) to obtain an (E)-hydroxyalkenal acetal compound (4), a functional group conversion reaction of (4) to obtain an (E)-alkenal acetal compound (5) having a leaving group X, an elimination reaction of (5) to obtain an (E)-dienal acetal compound (6), and a hydrolysis reaction of (6) to obtain the (E)-dienal compound (7); and others.

##STR00001##

Disclosed are processes and systems for making cyclohexanone from a mixture comprising phenol, cyclohexanone, and cyclohexylbenzene, comprising a step of or a device for subjecting at least a portion of the mixture to hydrogenation and a step of or a device for distilling a phenol/cyclohexanone/cyclohexylbenzene mixture to obtain an effluent rich in cyclohexanone.

Disclosed are processes and systems for making cyclohexanone from a mixture comprising phenol, cyclohexanone, and cyclohexylbenzene, comprising a step of or a device for subjecting at least a portion of the mixture to hydrogenation and a step of or a device for distilling a phenol/cyclohexanone/cyclohexylbenzene mixture to obtain an effluent rich in cyclohexanone.

Disclosed are processes and systems for making cyclohexanone from a mixture comprising phenol, cyclohexanone, and cyclohexylbenzene, comprising a step of or a device for subjecting at least a portion of the mixture to hydrogenation and a step of or a device for distilling a phenol/cyclohexanone/cyclohexylbenzene mixture to obtain an effluent rich in cyclohexanone.

A method of decomposing a phenol by-product produced in a phenol preparation process, in which acetophenone separated from a distillation column is mixed with tar separated and collected in a decomposition reactor, thereby significantly decreasing viscosity of tar. The decomposition method according to the present invention allows tar to have sufficient viscosity for flowability even at room temperature, whereby transfer and storage of tar may be more smoothly done without using any heating device for transfer of tar.

A method of decomposing a phenol by-product produced in a phenol preparation process, in which acetophenone separated from a distillation column is mixed with tar separated and collected in a decomposition reactor, thereby significantly decreasing viscosity of tar. The decomposition method according to the present invention allows tar to have sufficient viscosity for flowability even at room temperature, whereby transfer and storage of tar may be more smoothly done without using any heating device for transfer of tar.

A method of decomposing a phenol by-product produced in a phenol preparation process, in which acetophenone separated from a distillation column is mixed with tar separated and collected in a decomposition reactor, thereby significantly decreasing viscosity of tar. The decomposition method according to the present invention allows tar to have sufficient viscosity for flowability even at room temperature, whereby transfer and storage of tar may be more smoothly done without using any heating device for transfer of tar.

This present disclosure relates to processes and apparatuses for use of a single dividing wall distillation column for phenol fractionation. More specifically, the present disclosure relates to processes and apparatuses for phenol fractionation by combining crude acetone column and cumene-AMS column into a single dividing wall distillation column. The proper allocation of steam or water injection, chemical treatment reactor and internal liquid phase separator, the positioning of the side draw enables high yield of acetone and phenol.

This present disclosure relates to processes and apparatuses for use of a single dividing wall distillation column for phenol fractionation. More specifically, the present disclosure relates to processes and apparatuses for phenol fractionation by combining crude acetone column and cumene-AMS column into a single dividing wall distillation column. The proper allocation of steam or water injection, chemical treatment reactor and internal liquid phase separator, the positioning of the side draw enables high yield of acetone and phenol.