Abstract: The present invention relates to a method for carrying out a catalysed chemical reaction using one or more liquid reactants, preferably acetone and phenol, in an upflow reactor comprising feeding at least a portion of said reactants to a bottom section of the reactor positioned below a flow distributor plate, passing said portion through the flow distributor plate, passing said portion through a layer of inert particles positioned above and preferably in contact with said flow distributor plate, passing said portion through a catalyst layer comprising a particulate catalyst, said catalyst layer being positioned above and in contact with said layer of inert particles, wherein the reactants react to form a product stream, collecting said product stream via collecting means positioned above said catalyst layer. The invention also relates to a reactor assembly.

Abstract: In an embodiment, a reactor for carrying out a melt transesterification reaction at a reactor temperature of 160 to 300° C. and a reactor pressure of 5 to 200 mbar, comprises a cylindrical tank comprising a top, a side, and a bottom, wherein the bottom is convex, extending away from the top; a stirring shaft disposed within the cylindrical tank along an axis thereof so that it is rotatable from outside of the cylindrical tank; an impeller extending from the stirring shaft in the cylindrical tank and comprising a plurality of blades; a reactant solution inlet; a reaction solution outlet; and an externally located heat exchanger in fluid communication with the cylindrical tank via a recirculation stream and a heated stream. The reactor can be used for the polymerization of a polycarbonate oligomer.

Abstract: In an embodiment, a reactor for carrying out a melt transesterification reaction at a reactor temperature of 160 to 300° C. and a reactor pressure of 5 to 200 mbar, comprises a cylindrical tank comprising a top, a side, and a bottom, wherein the bottom is convex, extending away from the top; a stirring shaft disposed within the cylindrical tank along an axis thereof so that it is rotatable from outside of the cylindrical tank; a stirring blade extending from the stirring shaft in the cylindrical tank; a reactant solution inlet located on the bottom; and a reaction solution outlet located on the bottom. The reactor can be used for the polymerization of a polycarbonate oligomer.

Abstract: In an embodiment, a reactor for carrying out a melt transesterification reaction at a reactor temperature of 160 to 300° C. and a reactor pressure of 5 to 200 mbar, comprises a cylindrical tank comprising a top, a side, and a bottom, wherein the bottom is convex, extending away from the top; a stirring shaft disposed within the cylindrical tank along an axis thereof so that it is rotatable from outside of the cylindrical tank; a stirring blade extending from the stirring shaft in the cylindrical tank; a reactant solution inlet located on the bottom; and a reaction solution outlet located on the bottom. The reactor can be used for the polymerization of a polycarbonate oligomer.

Abstract: A polyetherimide of improved color and processes for preparing the polyetherimide are disclosed.

Abstract: The invention is directed to a catalyst, to a method for manufacturing a catalyst, to a method for manufacturing a bisphenol compound, and to the use of a catalyst. The catalyst of the invention comprises particles having a core and a shell, wherein the shell comprises an ion exchange resin covering the core at least in part and wherein the core has a density that is higher than the density of the ion exchange resin.

Abstract: The disclosure is directed to the use of an upflow reactor for producing a dihydroxy compound, to a method for producing a dihydroxy compound, and to a method for manufacturing polycarbonate. The upflow reactor for producing a dihydroxy compound of the disclosure comprises: a vessel; a catalyst bed disposed in said vessel; a distributor in fluid communication with an inlet through which reactants are introduced to said distributor, said distributor being disposed at a lower end of said vessel and comprising distributor perforation(s) disposed in said distributor, at least part of which distributor perforations are in a direction facing away from said catalyst bed; and a collector through which said product dihydroxy compound is removed, said collector being disposed at an upper end of said vessel.

Abstract: In an embodiment a method of purifying acetone, comprises directing a feed stream comprising greater than or equal to 97 wt % of acetone and 100 to 1,000 ppm of methanol to a separation column, both based on a total weight of the feed stream; separating the feed stream in the separation column that is operating at a pressure greater than or equal to 1 bar into an overhead stream and a purified acetone stream comprising less than or equal to 50 ppm of methanol based on a total weight of the purified acetone stream; and directing at least 80 wt % of the overhead stream into the separation column as a reconstituted stream and purging 1 to 20 wt % of the overhead stream as a purge stream.

Abstract: In an embodiment a method of purifying acetone, comprises directing a feed stream comprising greater than or equal to 97 wt % of acetone and 100 to 1,000 ppm of methanol to a separation column, both based on a total weight of the feed stream; separating the feed stream in the separation column that is operating at a pressure greater than or equal to 1 bar into an overhead stream and a purified acetone stream comprising less than or equal to 50 ppm of methanol based on a total weight of the purified acetone stream; and directing at least 80 wt % of the overhead stream into the separation column as a reconstituted stream and purging 1 to 20 wt % of the overhead stream as a purge stream.

Abstract: In an embodiment, a reactor for carrying out a melt transesterification reaction at a reactor temperature of 160 to 300° C. and a reactor pressure of 5 to 200 mbar, comprises a cylindrical tank comprising a top, a side, and a bottom, wherein the bottom is convex, extending away from the top; a stirring shaft disposed within the cylindrical tank along an axis thereof so that it is rotatable from outside of the cylindrical tank; a stirring blade extending from the stirring shaft in the cylindrical tank; a reactant solution inlet located on the bottom; and a reaction solution outlet located on the bottom. The reactor can be used for the polymerization of a polycarbonate oligomer.

Abstract: The disclosure is directed to the use of an upflow reactor for producing a dihydroxy compound, to a method for producing a dihydroxy compound, and to a method for manufacturing polycarbonate. The upflow reactor for producing a dihydroxy compound of the disclosure comprises: a vessel; a catalyst bed disposed in said vessel; a distributor in fluid communication with an inlet through which reactants are introduced to said distributor, said distributor being disposed at a lower end of said vessel and comprising distributor perforation(s) disposed in said distributor, at least part of which distributor perforations are in a direction facing away from said catalyst bed; and a collector through which said product dihydroxy compound is removed, said collector being disposed at an upper end of said vessel.

Abstract: In an embodiment, a reactor for carrying out a melt transesterification reaction at a reactor temperature of 160 to 300° C. and a reactor pressure of 5 to 200 mbar, comprises a cylindrical tank comprising a top, a side, and a bottom, wherein the bottom is convex, extending away from the top; a stirring shaft disposed within the cylindrical tank along an axis thereof so that it is rotatable from outside of the cylindrical tank; an impeller extending from the stirring shaft in the cylindrical tank and comprising a plurality of blades; a reactant solution inlet; a reaction solution outlet; and an externally located heat exchanger in fluid communication with the cylindrical tank via a recirculation stream and a heated stream. The reactor can be used for the polymerization of a polycarbonate oligomer.

Abstract: A polyetherimide of improved color and processes for preparing the polyetherimide are disclosed.

Abstract: A method of preparing a polyetherimide and an improved polyetherimide are disclosed. Low color polyetherimides are disclosed along with process improvements which produce the reduced color of the final product polymers.

Abstract: The invention is directed to the use of an upflow reactor for producing a dihydroxy compound, to a method for producing a dihydroxy compound, and to a method for manufacturing polycarbonate. The upflow reactor for producing a dihydroxy compound of the invention comprises: a vessel; a catalyst bed disposed in said vessel; a distributor in fluid communication with an inlet through which reactants are introduced to said distributor, said distributor being disposed at a lower end of said vessel and comprising distributor perforation(s) disposed in said distributor, at least part of which distributor perforations are in a direction facing away from said catalyst bed; and a collector through which said product dihydroxy compound is removed, said collector being disposed at an upper end of said vessel.

Abstract: A polyetherimide of improved color and processes for preparing the polyetherimide are disclosed.

Abstract: The invention is directed to the use of an upflow reactor for producing a dihydroxy compound, to a method for producing a dihydroxy compound, and to a method for manufacturing polycarbonate. The upflow reactor for producing a dihydroxy compound of the invention comprises: to a vessel; a catalyst bed disposed in said vessel; a distributor in fluid communication with an inlet through which reactants are introduced to said distributor, said distributor being disposed at a lower end of said vessel and comprising distributor perforation(s) disposed in said distributor, at least part of which distributor perforations are in a direction facing away from said catalyst bed; and a collector through which said product dihydroxy compound is removed, said collector being disposed at an upper end of said vessel.

Abstract: A polyetherimide of improved color and processes for preparing the polyetherimide are disclosed.

Abstract: A method of preparing a polyetherimide and an improved polyetherimide are disclosed. Low color polyetherimides are disclosed along with process improvements which produce the reduced color of the final product polymers.