Process for alkoxylation with DMC catalysts in a loop reactor with ejector

Abstract

The invention relates to a process for preparing polyethers of the formula (I) R1—(CHR2CHR3—O)n—H  (I) where n=1 to 12 000, R1=a radical comprising at least one carbon atom and R2 and R3 are each independently H or a hydrocarbon radical, where the units designated with the index n may be the same or different (the R2 and R3 radicals in the different units n may thus be the same or different), by alkoxylating a starter compound which comprises the R1 radical in the presence of a double metal cyanide catalyst (DMC catalyst) in a loop reactor, which is characterized in that the alkoxylation is performed in a loop reactor which has an ejector mixing nozzle, in which all substances involved in the reaction or assistants can be added to the circulated reaction mixture, an alkylene oxide or a plurality of different alkylene oxides being metered into the reaction mixture via the ejector mixing nozzle at the same time (random addition) or at different times (block addition).

Dependencies are inferred from the claim text.