PROCESS FOR PREPARING PROPYLENE OXIDE Russian patent published in 2019 - IPC C07D301/12 C07D301/36 C07D303/04 B01J29/70 B01J29/89 B01J27/18 B01J37/02 B01J37/10 

FIELD: chemistry.

SUBSTANCE: invention relates to a continuous process for the preparation of propylene oxide. Disclosed method comprises: (i) providing a liquid feed stream comprising propene, hydrogen peroxide, acetonitrile, water, optionally propane, and at least one dissolved potassium salt of a phosphorus oxyacid; (ii) passing the liquid feed stream provided in (i) into an epoxidation reactor comprising a catalyst comprising a titanium zeolite of structure type MWW comprising zinc, and subjecting the liquid feed stream to epoxidation reaction conditions in the epoxidation reactor, obtaining a reaction mixture comprising propylene oxide, acetonitrile, water, the at least one dissolved potassium salt of a phosphorus oxyacid, optionally propene, and optionally propane; (iii) removing an effluent stream from the epoxidation reactor, wherein the effluent stream comprising propylene oxide, acetonitrile, water, at least a portion of the at least one dissolved potassium salt of a phosphorus oxyacid, optionally propene, and optionally propane. Wherein at least one potassium salt of phosphorus oxyacid has following formula (I), in which n is 1, x is in the range from 0.6 to 1.4. Invention also relates to a catalytic system for the preparation of propylene oxide and the use of said potassium salt. K_nxH_2+n(1-x)P_nO_3n+1 (I).

EFFECT: technical result is the increased propylene oxide selectivity and a lower catalyst deactivation rate.

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