Abstract: A reactor for performing a gas/liquid biphasic high-pressure reaction with a foaming medium, comprising an interior formed by a cylindrical, vertically oriented elongate shell, a bottom and a cap, wherein the interior is divided by internals into a backmixed zone and a zone of limited backmixing, wherein the backmixed zone and the zone of limited backmixing are consecutively traversable by the reaction mixture, wherein the backmixed zone comprises means for introducing gas and liquid and a gas outlet and also comprises at least one mixing apparatus selected from a stirrer, a jet nozzle and means for injecting the gas, and the zone of limited backmixing comprises a reaction product outlet, a first cylindrical internal element which in the interior extends in the longitudinal direction of the reactor and which delimits the zone of limited backmixing from the backmixed zone, backmixing-preventing second internal elements in the form of random packings, structured packings or liquid-permeable trays arranged in th

Abstract: A process for performing a continuous gas/liquid biphasic high-pressure reaction, wherein a gas and a liquid are introduced into a backmixed zone of a reactor and in the backmixed zone the gas is dispersed in the liquid by stirring, injection of gas and/or a liquid jet, a reaction mixture consecutively traverses the backmixed zone and a zone of limited backmixing, and a liquid reaction product is withdrawn at a reaction product outlet of the zone of limited backmixing, wherein the reactor comprises: an interior formed by a cylindrical vertically oriented elongate shell, a bottom and a cap, wherein the interior is divided by means of internals into the backmixed zone, the zone of limited backmixing and a cavity, a first cylindrical internal element which in the interior extends in the longitudinal direction of the reactor and which delimits the zone of limited backmixing from the backmixed zone, backmixing-preventing second internal elements in the form of random packings, structured packings or liquid-permeab

Abstract: A reactor for performing a reaction between two immiscible fluids of different density, comprising an interior formed by a cylindrical, vertically oriented elongate shell, a bottom and a cap, wherein the interior is divided by internals into a backmixed zone, a zone of limited backmixing preferably arranged below the backmixed zone and a plug-flow zone which are at least consecutively traversable by one of the fluids, wherein the backmixed zone comprises at least one inlet and the plug-flow zone comprises an outlet and the backmixed zone comprises at least one mixing apparatus selected from a stirrer, a jet nozzle and means for injecting the fluid of lower density, a first cylindrical internal element which in the interior extends in the longitudinal direction of the reactor, which delimits the zone of limited backmixing from the plug-flow zone and which comprises a first passage to the backmixed zone and a second passage to the plug-flow zone, a second internal element which delimits the backmixed zone from

Abstract: A reactor for performing a gas/liquid biphasic high-pressure reaction with a foaming medium, comprising an interior formed by a cylindrical, vertically oriented elongate shell, a bottom and a cap, wherein the interior is divided by internals into a backmixed zone and a zone of limited backmixing, wherein the backmixed zone and the zone of limited backmixing are consecutively traversable by the reaction mixture, wherein the backmixed zone comprises means for introducing gas and liquid and a gas outlet and also comprises at least one mixing apparatus selected from a stirrer, a jet nozzle and means for injecting the gas, and the zone of limited backmixing comprises a reaction product outlet, a first cylindrical internal element which in the interior extends in the longitudinal direction of the reactor and which delimits the zone of limited backmixing from the backmixed zone, backmixing-preventing second internal elements in the form of random packings, structured packings or liquid-permeable trays arranged in th

Abstract: A process for performing a continuous gas/liquid biphasic high-pressure reaction, wherein a gas and a liquid are introduced into a backmixed zone of a reactor and in the backmixed zone the gas is dispersed in the liquid by stirring, injection of gas and/or a liquid jet, a reaction mixture consecutively traverses the backmixed zone and a zone of limited backmixing, and a liquid reaction product is withdrawn at a reaction product outlet of the zone of limited backmixing, wherein the reactor comprises: an interior formed by a cylindrical vertically oriented elongate shell, a bottom and a cap, wherein the interior is divided by means of internals into the backmixed zone, the zone of limited backmixing and a cavity, a first cylindrical internal element which in the interior extends in the longitudinal direction of the reactor and which delimits the zone of limited backmixing from the backmixed zone, backmixing-preventing second internal elements in the form of random packings, structured packings or liquid-permeab

Abstract: A reactor for performing a reaction between two immiscible fluids of different density, comprising an interior formed by a cylindrical, vertically oriented elongate shell, a bottom and a cap, wherein the interior is divided by internals into a backmixed zone, a zone of limited backmixing preferably arranged below the backmixed zone and a plug-flow zone which are at least consecutively traversable by one of the fluids, wherein the backmixed zone comprises at least one inlet and the plug-flow zone comprises an outlet and the backmixed zone comprises at least one mixing apparatus selected from a stirrer, a jet nozzle and means for injecting the fluid of lower density, a first cylindrical internal element which in the interior extends in the longitudinal direction of the reactor, which delimits the zone of limited backmixing from the plug-flow zone and which comprises a first passage to the backmixed zone and a second passage to the plug-flow zone, a second internal element which delimits the backmixed zone from

Abstract: An &agr;,&bgr;-unsaturated carbonyl compound of formula (I) where R1 is saturated C1-40-hydrocarbyl or a substituted or unsubstituted aromatic radical containing moiety, and R2, R3 and R4, independently of one another, are hydrogen or a C1- to C4-alkyl group, is selectively hydrogenated in the liquid phase to a saturated carbonyl compound of formula (II) with hydrogen in the presence of a pulverulent palladium and/or rhodium catalyst and in the presence of an organic base, by conducting the hydrogenation in a packed bubble column reactor in which product is recycled and hydrogen gas is recirculated.

Abstract: A process for preparing .alpha.,.alpha.-dialkoxy ketones of the formula I ##STR1## where R.sup.1 and R.sup.2 are each, independently of one another, hydrogen, C.sub.1 -C.sub.20 -alkyl, C.sub.3 -C.sub.20 -cycloalkyl, C.sub.4 -C.sub.30 -cycloalkylakyl, C.sub.9 -C.sub.30 -alkylcycloalkyl, unsubstituted or C.sub.1 -C.sub.8 -alkyl, C.sub.1 -C.sub.8 -alkoxy-, halogen-, C.sub.1 -C.sub.4 -haloalkyl-, C.sub.1 -C.sub.4 -haloalkoxy-, phenyl-, phenoxy-, halophenyl-, halophenoxy- and/or cyano-substituted aryl, C.sub.7 -C.sub.20 -aralkyl or heterocyclyl,R.sup.2 is also ##STR2## R.sup.3 and R.sup.4 are each, independently of one another, C.sub.1 -C.sub.20 -alkyl, C.sub.3 -C.sub.20 -cycloalkyl, aryl, C.sub.7 -C.sub.20 -arylalkyl, or together are an unsubstituted or C.sub.1-C.sub.4 -alkyl- substituted C.sub.2 -C.sub.7 -alkylene chain andR.sup.5 is R.sup.1 or together with R.sup.1 is an unsubstituted or C.sub.1 -C.sub.4 -alkyl-substituted C.sub.2 -C.sub.

Abstract: Ethereal solutions of arylmethylmagnesium halidesAr--CH.sub.2 --Mg--Hal I(where Ar is unsubstituted or substituted aryl and Hal is Cl or Br) are prepared by the Grignard method from an arylmethyl halide IIAr--CH.sub.2 --Hal IIand magnesium in an ether IIItert-butyl--O--R III(where R is C.sub.1 -C.sub.3 -alkyl) as solvent.