Abstract: A process for the storage or transportation of pretreated, conditioned ion exchangers as catalysts for chemical reactions is disclosed. The preconditioned ion-exchange resin is kept as preconditioned ion-exchange resin suspension in a storage or transporting container. The container with the preconditioned ion-exchange resin suspension is transported to either a storage site for storage or to a reactor for transfer of the resin to the reactor.

Abstract: The invention describes a process for producing bisphenol with a content of less than 15 wt. % of phenol, wherein a suspension crystallisation of a product mixture containing bisphenol A, minor components and phenol is performed in a crystalliser, the product mixture being pumped through a heat exchanger. Due to deposition (fouling, i.e. crystallisation and deposition on the surface of the heat exchangers) in the heat exchanger, the pressure difference increases from 0.5 to 3 bar across the heat exchanger. The resulting reduced flow rate, which would lead to increased fouling in the crystalliser, is offset by continuously increasing the speed of the pump, the pump speed being regulated in such a way that the current consumption of the pump is maintained such that it fluctuates by a maximum of 5%.

Abstract: A process for the preparation of high purity bisphenol A is disclosed. The multi-step process entails a process whereby bisphenol A of a purity of preferably at least 99.8% can be obtained.

Abstract: Processes for producing bisphenols (e.g., bisphenol A (BPA)) having a purity greater than 99.7% are described, such processes including reacting a phenol and acetone in the presence of an acidic catalyst to form a product mixture comprising a bisphenol; removing at least a portion of the bisphenol from the product mixture in the form of a bisphenol/phenol adduct by crystallization, filtration and washing to provide bisphenol/phenol adduct crystals; and removing at least a portion of the phenol from the bisphenol/phenol adduct crystals to provide the bisphenol having a purity of more than 99.7%; wherein the crystallization comprises continuous suspension crystallization and is carried out in at least three crystallization devices arranged such that the product mixture is first cooled in a first stage of the crystallization to a temperature of 50 to 70° C.

Abstract: A process for the preparation of high purity bisphenol A is disclosed. The multi-step process entails a process whereby bisphenol A of a purity of preferably at least 99.8% can be obtained.

Abstract: A branched polycarbonate and processes for its preparation are disclosed. The polycarbonate contains structural units conforming to in which R1, R2, R3 and R4 mutually independently denote C1-C10 alkyl, R5, R6 and R7 mutually independently denote hydrogen or C1-C10 alkyl, or R1 and R2, and R3 and R4, with the carbon atom to which they are attached, form a C5-C10 cycloalkyl group, wherein the cycloalkyl group may be substituted.

Abstract: A process for the preparation of high purity bisphenol A is disclosed. The multi-step process entails a process whereby bisphenol A of a purity of preferably at least 99.8% can be obtained.

Abstract: A process for the production of bisphenol-A having low concentration of sulphur is disclosed. The process comprise a) reacting phenol with acetone in the presence of a sulfonic acid ion exchanger to form a product mixture containing water, bisphenol-A/phenol adduct, phenol and sulfurous particles, and b) filtering the product mixture to separate the sulfurous particles to obtain a purified product mixture that contains water, phenol and bisphenol-A/phenol adduct. In one embodiment of the process further comprise distilling the purified product mixture to remove the water to obtain a first material system that contains said adduct and phenol, crystallizing the adduct, and removing the phenol by filtration using a filtering apparatus to obtain crystalline adduct.

Abstract: A process for producing bisphenol A is disclosed. The process entails a) reacting phenol with acetone in the presence of an acidic catalyst to form a reaction mixture that includes bisphenol A and water, and b) removing water from the reaction mixture by distillation in a column to obtain a bottom product, and c) separating bisphenol-A/phenol adduct from the reaction mixture by crystallization and filtration. The bottom temperature of the column is 100 to 150° C., the overhead temperature of the column is 20 to 80° C., the absolute pressure is 50 to 300 mbar at the head of the column and 100 to 300 mbar at the bottom of the column, and wherein said (c) is carried out before or after said (b).

Abstract: A branched polycarbonate and processes for its preparation are disclosed. The polycarbonate contains structural units conforming to in which R1, R2, R3 and R4 mutually independently denote C1-C10 alkyl, R5, R6 and R7 mutually independently denote hydrogen or C1-C10 alkyl, or R1 and R2, and R3 and R4, with the carbon atom to which they are attached, form a C5-C10 cycloalkyl group, wherein the cycloalkyl group may be substituted.

Abstract: A process for the preparation of polycarbonate by the phase interface process is disclosed. The process includes (a) preparing a sodium hydroxide solution by chloralkali electrolysis, the solution containing not more than 30 ppm sodium chlorate relative to the weight of sodium hydroxide, and (b) reacting an aqueous solution of said sodium hydroxide with at least one dihydoxydiarylalkane to obtain a solution of disodium salt and (c) reacting said solution of disodium salt with phosgene in the presence of at least one organic solvent, a chain terminator and optionally a branching agent to obtain an oligocarbonate, and (d) condensing the oligocarbonate in the presence of at least one catalyst to obtain a material system containing polycarbonate and organic solvent and (e) separating off of the organic phase from said material system. The polycarbonate prepared by the inventive process is characterized by its low yellowness index.

Abstract: A process for extracting phenol from a phenol-containing aqueous solution is disclosed. The process entails contacting the aqueous solution with an extracting agent that comprise a mixture of 60 to 99% of methyl isobutyl ketone, 1 to 40% of anisole and 0 to 20% of mesitylene.

Abstract: A process for extracting phenol from a phenol-containing aqueous solution is disclosed. The process entails contacting the aqueous solution with an extracting agent that comprise a mixture of 60 to 99% of methyl isobutyl ketone, 1 to 40% of anisole and 0 to 20% of mesitylene.

Abstract: A process for the production of bisphenol-A having low concentration of sulphur is disclosed. The process comprise a) reacting phenol with acetone in the presence of a sulfonic acid ion exchanger to form a product mixture containing water, bisphenol-A/phenol adduct, phenol and sulfurous particles, and b) filtering the product mixture to separate the sulfurous particles to obtain a purified product mixture that contains water, phenol and bisphenol-A/phenol adduct. In one embodiment of the process further comprise distilling the purified product mixture to remove the water to obtain a first material system that contains said adduct and phenol, crystallizing the adduct, and removing the phenol by filtration using a filtering apparatus to obtain crystalline adduct.

Abstract: The present invention relates to a process for preparing bisphenol A in which the phenol and acetone are reacted to give bisphenol A in the presence of a sulfonic acid ion-exchanger in at least one reactor, and in which the reactor, at the time when it is started up, is filled with sulfonic acid ion-exchanger with a bulk volume of 30 to 70 vol. % of the total reactor volume.

Abstract: A process for producing bisphenol A is disclosed. The process entails a) reacting phenol with acetone in the presence of an acidic catalyst to form a reaction mixture that includes bisphenol A and water, and b) removing water from the reaction mixture by distillation in a column to obtain a bottom product, and c) separating bisphenol-A/phenol adduct from the reaction mixture by crystallization and filtration. The bottom temperature of the column is 100 to 150° C., the overhead temperature of the column is 20 to 80° C., the absolute pressure is 50 to 300 mbar at the head of the column and 100 to 300 mbar at the bottom of the column, and wherein said (c) is carried out before or after said (b).

Abstract: A process for the production of bisphenol A is disclosed. The process entails a) mixing phenol and acetone to form a mixture, and b) bringing the mixture to a temperature of 48 to 54° C. to form a warm mixture, and c) commencing a reaction between phenol and acetone upon contacting the warm mixture with an acid ion exchange catalyst to form a product mixture that contains bisphenol A. The bisphenol A may be extracted from the product mixture by crystallization and filtration.