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US 6,723,881 B1Granted
Method for conditioning ion exchangers
AssigneeBayer Aktiengesellschaft
InventorsMichael Bödiger, Rainer Neumann, Frieder Heydenreich, Michael Prein, Gerhard Fennhoff, Ulrich Schnegg, Rudolf Wagner, Wolfgang Wambach, Reinhold Klipper
Life of this patent
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Abstract
Monodisperse cation-exchangers and anon-exchangers are conditioned by a process and thereafter used as catalysts and for the production of bisphenols.
Claims8
A process for conditioning monodisperse ion-exchangers for the catalysis of condensation reactions, addition reactions, transesterifications, esterifications or alkylation reactions, comprising the steps of
- a) moistening monodisperse ion-exchangers with water,
- b) suspending the moistened ion-exchangers in oxygen-free completely de-ionized water,
- c) washing the suspended ion-exchanger with oxygen-free completely deionized water until constant conductivity is attained,
- d) after washing, discharging the completely de-ionized water,
- e) admixing an oxygen-free OH component to the monodisperse ion-exchanger,
- f) dehydrating the mixture in a continuously operated circulating apparatus with a distillation unit, and
- g) transferring the suspension comprising the monodisperse ion-exchanger and OH component into a reaction vessel.
4 more elements
A process for conditioning ion-exchangers, comprising the steps of
- a) moistening the ion-exchanger with water,
- b) suspending the moistened ion-exchanger in a unit with oxygen-free, completely de-ionized water at about 5 to about 80° C.,
- c) agitating the suspension,
- d) discontinuously washing the ion-exchanger with oxygen-free, completely de-ionized water until constant residual conductivity is attained,
- e) after washing, discharging the completely de-ionized water,
- f) admixing oxygen-free phenol to the ion-exchanger at temperatures from about 50 to about 90° C. to form a mixture,
- g) dehydrating the mixture in a continuously operated circulating apparatus containing the unit and at least one distillation unit for the purpose of separating phenol and water,
- h) transferring the ion-exchanger/phenol suspension into a reaction vessel.
5 more elements
Dependencies are inferred from the claim text.