Abstract: A method for preparing 1,2-propanediol involves reacting propene with hydrogen peroxide, in the presence of a phase transfer catalyst and a heteropolytungstate, in a liquid reaction mixture containing an aqueous phase with a maximum apparent pH of 6 and an organic phase containing a solvent having a solubility in water at 20° C. of less than 500 mg/kg. The method then involves separating the liquid reaction mixture into an aqueous phase containing 1,2-propanediol and an organic phase; recycling at least a part of the separated organic phase to the reaction; and extracting the separated aqueous phase with an extractant solution containing the same phase transfer catalyst and solvent as used in the reaction to provide an extracted aqueous phase and an extract phase. The method further involves recycling at least a part of the extract phase to the reaction and recovering 1,2-propanediol from the extracted aqueous phase.

Abstract: A process has the ability to produce polyalkenamer-containing compositions. Stages of the process include converting at least one cycloalkene by ring-opening metathetic polymerization to obtain a polyalkenamer-containing product mixture, and working up the product mixture to remove at least one of a monomer and an oligomer of the at least one cycloalkene to obtain the polyalkenamer-containing composition. The working up stage is effected by a diafiltration.

Abstract: A process has the ability to produce polyalkenamer-containing compositions. Stages of the process include converting at least one cycloalkene by ring-opening metathetic polymerization to obtain a polyalkenamer-containing product mixture, and working up the product mixture to remove at least one of a monomer and an oligomer of the at least one cycloalkene to obtain the polyalkenamer-containing composition. The working up stage is effected by a diafiltration.

Abstract: The invention relates to processes for preparing aldehydes by hydroformylation of alkenes, in which an alkene-containing feed mixture is subjected to a primary hydroformylation with synthesis gas in the presence of a homogeneous catalyst system, the primary hydroformylation being effected in a primary reaction zone from which a cycle gas containing at least some of the products and unconverted reactants of the primary hydroformylation are drawn off continuously and partly condensed, with recycling of uncondensed components of the cycle gas into the primary reaction zone, and with distillative separation of condensed components of the cycle gas in an aldehyde removal stage to give an aldehyde-rich mixture and a low-aldehyde mixture. The problem that it addresses is that of developing the process such that it achieves high conversions and affords aldehyde in good product quality even in the case of a deteriorating raw material position.

Abstract: Composite membrane having a separating membrane layer characterized in that a separating membrane layer is produced by curing laterally modified silicone acrylates of the general Formula I

Abstract: The invention relates to processes for preparing aldehydes by hydroformylation of alkenes, in which an alkene-containing feed mixture is subjected to a primary hydroformylation with synthesis gas in the presence of a homogeneous catalyst system, the primary hydroformylation being effected in a primary reaction zone from which a cycle gas containing at least some of the products and unconverted reactants of the primary hydroformylation are drawn off continuously and partly condensed, with recycling of uncondensed components of the cycle gas into the primary reaction zone, and with distillative separation of condensed components of the cycle gas in an aldehyde removal stage to give an aldehyde-rich mixture and a low-aldehyde mixture. The problem that it addresses is that of developing the process such that it achieves high conversions and affords aldehyde in good product quality even in the case of a deteriorating raw material position.

Abstract: Composite membrane having a separating membrane layer characterized in that a separating membrane layer is produced by curing laterally modified silicone acrylates of the general Formula I