METHOD FOR PRODUCING POLYETHER POLYOLS IN THE PRESENCE OF A MULTI-METAL CYANIDE COMPLEX CATALYST

摘要

Production of polyether polyols comprises use of a multi-metal cyanide complex catalyst in a tall cylindrical reactor having a downward facing spray nozzle in the upper reactor portion, through which the educts and reaction mixture are fed and an outlet, preferably in the lower portion of the reactor to recirculate the reaction mixture via an external circuit and equalizing reservoir. A process for the production of polyether polyols (I) by reaction of diols or polyols with ethylene oxide, propylene oxide and/or butylene oxide in the presence of a multi-metal cyanide complex catalyst (II) comprises carrying out the reaction in a tall cylindrical reactor having a downward facing spray nozzle in the upper reactor portion, through which the educts and reaction mixture are fed, and an outlet, preferably in the lower portion of the reactor, through which the reaction mixture is fed by means of a pump through an external circuit via an equalizing reservoir to the spray nozzle. The external circuit comprises a concentric pipe stretching the entire length of the reactor excluding the reactor ends and contains a heat exchanger integrated within the annulus.