The disclosure concerns systems and methods for the production of phenol and acetone from cumene oxidation products. One method comprises reacting cumene and an oxidizing agent to produce a cumene oxidation product comprising cumene hydroperoxide and dimethyl benzyl alcohol, converting at least a portion of the dimethyl benzyl alcohol to cumene hydroperoxide by reacting the at least a portion of the dimethyl benzyl alcohol with hydrogen peroxide in both an organic phase and an aqueous to produce a converted cumene oxidation product, and cleaving the converted cumene oxidation product to produce an output product comprising one or more of phenol, acetone, and alpha-methylstyrene.

The disclosure concerns systems and methods for the production of phenol and acetone from cumene oxidation products. One method comprises reacting cumene and an oxidizing agent to produce a cumene oxidation product comprising cumene hydroperoxide and dimethyl benzyl alcohol, converting at least a portion of the dimethyl benzyl alcohol to cumene hydroperoxide by reacting the at least a portion of the dimethyl benzyl alcohol with hydrogen peroxide in both an organic phase and an aqueous to produce a converted cumene oxidation product, and cleaving the converted cumene oxidation product to produce an output product comprising one or more of phenol, acetone, and alpha-methylstyrene.

The present invention relates to a method for operating a phosgene generator for producing phosgene by reacting carbon monoxide with chlorine in the gas phase on an activated carbon catalyst arranged in a reaction chamber, in which method, after a predefinable operating period, the phosgene production is at least temporarily interrupted by shutting down the phosgene generator over a shutdown period and, after a predefinable downtime, is resumed by starting up the phosgene generator over a start-up period, wherein the method is characterized in that the activated carbon catalyst, before the phosgene generator is started up, is freed of chlorine by adding carbon monoxide so that, during the start-up period, a maximum concentration of chlorine in the gas stream immediately downstream of the reaction chamber of 1000 ppmv is not exceeded. The invention also relates to the use of the phosgene thus obtained in the production of polycarbonate and isocyanates.

The present invention relates to a method for operating a phosgene generator for producing phosgene by reacting carbon monoxide with chlorine in the gas phase on an activated carbon catalyst arranged in a reaction chamber, in which method, after a predefinable operating period, the phosgene production is at least temporarily interrupted by shutting down the phosgene generator over a shutdown period and, after a predefinable downtime, is resumed by starting up the phosgene generator over a start-up period, wherein the method is characterized in that the activated carbon catalyst, before the phosgene generator is started up, is freed of chlorine by adding carbon monoxide so that, during the start-up period, a maximum concentration of chlorine in the gas stream immediately downstream of the reaction chamber of 1000 ppmv is not exceeded. The invention also relates to the use of the phosgene thus obtained in the production of polycarbonate and isocyanates.

The invention relates to a process for drying a catalyst carrier or drying a catalyst comprising a carrier on which a metal is supported, wherein the carrier or catalyst is contacted with a drying agent which comprises an organic carbonate. Further, the invention relates to a process for preparing a catalyst which comprises a carrier on which a metal is supported, said process comprising drying the carrier by contacting the carrier with a drying agent which comprises an organic carbonate resulting in a dried carrier; and impregnating the dried carrier with a solution wherein a compound containing the metal is dissolved in a solvent which is an organic carbonate or an alcohol. Still further, the invention relates to a process for preparing an aromatic carbonate, such as a diaryl carbonate, using the catalyst thus prepared or dried; and to a process for making a polycarbonate from the diaryl carbonate thus prepared.

The invention relates to a process for drying a catalyst carrier or drying a catalyst comprising a carrier on which a metal is supported, wherein the carrier or catalyst is contacted with a drying agent which comprises an organic carbonate. Further, the invention relates to a process for preparing a catalyst which comprises a carrier on which a metal is supported, said process comprising drying the carrier by contacting the carrier with a drying agent which comprises an organic carbonate resulting in a dried carrier; and impregnating the dried carrier with a solution wherein a compound containing the metal is dissolved in a solvent which is an organic carbonate or an alcohol. Still further, the invention relates to a process for preparing an aromatic carbonate, such as a diaryl carbonate, using the catalyst thus prepared or dried; and to a process for making a polycarbonate from the diaryl carbonate thus prepared.

A method of preparing a polycarbonate composition in a polymerization system that comprises a monomer mixing unit, an oligomerization section, and a polymerization section. The method includes melt polymerizing a dihydroxy compound with a diaryl carbonate compound in the presence of a quaternary phosphonium catalyst to produce the polycarbonate composition having a phosphorus-containing byproduct of at least one of the quaternary phosphonium catalyst or of the diaryl carbonate compound. The method further includes recycling the phosphorus-containing byproduct into the monomer mixing unit of the polymerization system and removing the polycarbonate composition from the polymerization system. The recycle stream has a phosphorus concentration of greater than or equal to 40 ppm.

A method of preparing a polycarbonate composition in a polymerization system that comprises a monomer mixing unit, an oligomerization section, and a polymerization section. The method includes melt polymerizing a dihydroxy compound with a diaryl carbonate compound in the presence of a quaternary phosphonium catalyst to produce the polycarbonate composition having a phosphorus-containing byproduct of at least one of the quaternary phosphonium catalyst or of the diaryl carbonate compound. The method further includes recycling the phosphorus-containing byproduct into the monomer mixing unit of the polymerization system and removing the polycarbonate composition from the polymerization system. The recycle stream has a phosphorus concentration of greater than or equal to 40 ppm.

The objective of the present invention is to provide a method for producing a polycarbonate safely and efficiently even without using a base. The method for producing a carbonate derivative according to the present invention is characterized in comprising the step of irradiating a high energy light to a composition comprising the halogenated methane and the hydroxy group-containing compound in the presence of oxygen, wherein a molar ratio of a total usage amount of the hydroxy group-containing compound to 1 mole of the halogenated methane is 0.05 or more.

A bisphenol composition including 95% or more by mass of a bisphenol, wherein a bisphenol represented by the following general formula (II) in the bisphenol composition constitutes 150 mass ppm or more, and the bisphenol composition has a methanol dissolution color (Hazen color number) of 2 or less,

##STR00001##

In formula (II), X denotes a single bond, —CR.sup.11R.sup.12—, —O—, —CO—, —S—, —SO—, or —SO.sub.2—, R.sup.11 and R.sup.12 independently denote a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and R.sup.11 and R.sup.12 may be bonded to each other to form a ring. A method for producing a polycarbonate resin using the bisphenol composition is also described.