METHOD FOR PRODUCING A POLYCARBONATE USING A STRIPPING APPARATUS Russian patent published in 2021 - IPC C07C68/08 C08G64/30 C07C39/16 C07C69/96 B01D3/00 C07C37/04 

FIELD: chemistry.

SUBSTANCE: invention relates to a method for producing a polycarbonate by means of reaction of one or more diaryl carbonates with one or more aromatic hydroxy compounds, first mixed in a mixing apparatus and placed in a reservoir for a mixture of raw materials in form of a mixture of raw materials in order to further execute a reaction thereof in one or more reactors at reduced pressure and increased temperature producing polycarbonate. The mixture of diaryl carbonate and the aromatic hydroxy compound therein is subjected to a counter-flow purifying process with an inert gas in a stripping apparatus prior to being supplied to the reservoir for the mixture of raw materials. The present invention also relates to a stripping apparatus particularly well suited for purifying a stream of a mixture of raw materials. The stripping apparatus for counter-flow purification of a stream of a mixture of raw materials by a gas in a method for producing polycarbonate comprises a column area with structured attachments and a preheating zone for preheating the gas. The stripping apparatus is configured to connect and be vacuum-sealed by means of welded lip seals. Also described is an application of the stripping apparatus in a method for producing polycarbonate.

EFFECT: technical result is increased quality of raw materials due to counter-flow purification of the mixture of raw materials, improved mass transfer and, accordingly, reduced equipment costs compared with those that would arise in case of a stream of pure raw material constituting a hydroxy compound; additionally, the solidification temperature of the mixture is below the solidification temperature of the aromatic hydroxy compound component, therefore, additional heat supply is not required to compensate for evaporation losses.

16 cl, 3 dwg