The invention relates to a process for preparing propylene oxide, comprising (i) providing a stream comprising propene, propane, hydrogen peroxide or a source of hydrogen peroxide, water, and an organic solvent; (ii) passing the liquid feed stream provided in (i) into an epoxidation zone comprising an epoxidation catalyst comprising a titanium zeolite, and subjecting the liquid feed stream to epoxidation reaction conditions in the epoxidation zone, obtaining a reaction mixture comprising propene, propane, propylene oxide, water, and the organic solvent; (iii) removing an effluent stream from the epoxidation zone, the effluent stream comprising propene, propane, propylene oxide, water, and the organic solvent; (iv) separating propene and propane from the effluent stream by distillation, comprising subjecting the effluent stream to distillation conditions in a distillation unit, obtaining a gaseous stream (S1) which is enriched in propene and propane compared to the effluent stream subjected to distillation conditions, and a liquid bottoms stream (S2) which is enriched in propylene oxide, water and organic solvent compared to the effluent stream subjected to distillation conditions; (v) separating propane from the stream (S1) in a separation zone, comprising subjecting the stream (S1) to washing conditions in a scrubber, wherein a solvent mixture comprising organic solvent and water is added as entraining agent, obtaining a bottoms stream (S3), which comprises organic solvent, water and at least 70 weight-% of the propene comprised in (S1); and a gaseous top stream (S4), which comprises at least 5 weight-% of the propane comprised in stream (S1).

The invention relates to a process for preparing propylene oxide, comprising (i) providing a stream comprising propene, propane, hydrogen peroxide or a source of hydrogen peroxide, water, and an organic solvent; (ii) passing the liquid feed stream provided in (i) into an epoxidation zone comprising an epoxidation catalyst comprising a titanium zeolite, and subjecting the liquid feed stream to epoxidation reaction conditions in the epoxidation zone, obtaining a reaction mixture comprising propene, propane, propylene oxide, water, and the organic solvent; (iii) removing an effluent stream from the epoxidation zone, the effluent stream comprising propene, propane, propylene oxide, water, and the organic solvent; (iv) separating propene and propane from the effluent stream by distillation, comprising subjecting the effluent stream to distillation conditions in a distillation unit, obtaining a gaseous stream (S1) which is enriched in propene and propane compared to the effluent stream subjected to distillation conditions, and a liquid bottoms stream (S2) which is enriched in propylene oxide, water and organic solvent compared to the effluent stream subjected to distillation conditions; (v) separating propane from the stream (S1) in a separation zone, comprising subjecting the stream (S1) to washing conditions in a scrubber, wherein a solvent mixture comprising organic solvent and water is added as entraining agent, obtaining a bottoms stream (S3), which comprises organic solvent, water and at least 70 weight-% of the propene comprised in (S1); and a gaseous top stream (S4), which comprises at least 5 weight-% of the propane comprised in stream (S1).

A method for producing propylene oxide involves an oxidation step, a distillation step, an epoxidation step, and a separation step. The distillation step involves distilling the reaction mixture containing cumene hydroperoxide to separate it into a concentrate containing cumene hydroperoxide and a distillate. The reaction mixture is continuously distilled so that the ratio of the flow rate of the distillate to the flow rate of the reaction mixture to be distilled is 0.037 to 0.13. The epoxidation step involves obtaining a reaction mixture containing propylene oxide and cumyl alcohol by contacting the concentrate with propylene in the presence of a catalyst in one or more reactors to cause a reaction between propylene and cumene hydroperoxide in the concentrate, in which the outlet temperature of the final reactor is adjusted to 115 C. or more and less than 140 C.

A method for producing propylene oxide involves an oxidation step, a distillation step, an epoxidation step, and a separation step. The distillation step involves distilling the reaction mixture containing cumene hydroperoxide to separate it into a concentrate containing cumene hydroperoxide and a distillate. The reaction mixture is continuously distilled so that the ratio of the flow rate of the distillate to the flow rate of the reaction mixture to be distilled is 0.037 to 0.13. The epoxidation step involves obtaining a reaction mixture containing propylene oxide and cumyl alcohol by contacting the concentrate with propylene in the presence of a catalyst in one or more reactors to cause a reaction between propylene and cumene hydroperoxide in the concentrate, in which the outlet temperature of the final reactor is adjusted to 115 C. or more and less than 140 C.

A preparation method for a propylene epoxidation catalyst: pre-hydrolyzing a silicon source, adding a titanium source and reacting to form a sol, atomizing the sol and then spraying it into liquid ammonia for molding, implementing pore broadening, and performing drying, calcination, and silanization treatment to obtain a TiSiO.sub.2 composite oxide catalyst. The present catalyst can be used in the chemical process of preparing propylene oxide by epoxidation of propylene, the average propylene oxide selectivity being up to 97.5%, having prospects for industrial application.

Disclosed in the present invention are a preparation method for an olefin epoxidation catalyst and applications thereof. The method comprises: loading an auxiliary metal salt onto a silica gel carrier, and carrying out a drying treatment to the silica gel carrier; loading a titanium salt (preferably TiCl.sub.4) onto the silica gel carrier by a chemical vapor deposition method; calcining to obtain a silica gel on which the auxiliary metal oxide and Ti species are loaded; obtaining an catalyst precursor (Ti-MeOSiO.sub.2 composite oxide) by water vapor washing; loading alkyl silicate (preferably tetraethyl orthosilicate) onto the surface of the catalyst precursor by a chemical vapor deposition method and calcining the catalyst precursor to obtain a Ti-MeOSiO.sub.2 composite oxide with the surface coated with a SiO.sub.2 layer; and carrying out a silylanization treatment to obtain the catalyst. The catalyst can be applied to a chemical process of propylene epoxidation to prepare propylene oxide, and has an average selectivity to PO up to 96.7%, the method of the present invention and the applications thereof have industrial application prospects.

Disclosed in the present invention are a preparation method for an olefin epoxidation catalyst and applications thereof. The method comprises: loading an auxiliary metal salt onto a silica gel carrier, and carrying out a drying treatment to the silica gel carrier; loading a titanium salt (preferably TiCl.sub.4) onto the silica gel carrier by a chemical vapor deposition method; calcining to obtain a silica gel on which the auxiliary metal oxide and Ti species are loaded; obtaining an catalyst precursor (Ti-MeOSiO.sub.2 composite oxide) by water vapor washing; loading alkyl silicate (preferably tetraethyl orthosilicate) onto the surface of the catalyst precursor by a chemical vapor deposition method and calcining the catalyst precursor to obtain a Ti-MeOSiO.sub.2 composite oxide with the surface coated with a SiO.sub.2 layer; and carrying out a silylanization treatment to obtain the catalyst. The catalyst can be applied to a chemical process of propylene epoxidation to prepare propylene oxide, and has an average selectivity to PO up to 96.7%, the method of the present invention and the applications thereof have industrial application prospects.

A method for producing propylene oxide involves an oxidation step, a distillation step, an epoxidation step, and a separation step. The distillation step involves distilling the reaction mixture containing cumene hydroperoxide to separate it into a concentrate containing cumene hydroperoxide and a distillate. The reaction mixture is continuously distilled so that the ratio of the flow rate of the distillate to the flow rate of the reaction mixture to be distilled is 0.037 to 0.13. The epoxidation step involves obtaining a reaction mixture containing propylene oxide and cumyl alcohol by contacting the concentrate with propylene in the presence of a catalyst in one or more reactors to cause a reaction between propylene and cumene hydroperoxide in the concentrate, in which the outlet temperature of the final reactor is adjusted to 115 C. or more and less than 140 C.

A method for producing propylene oxide involves an oxidation step, a distillation step, an epoxidation step, and a separation step. The distillation step involves distilling the reaction mixture containing cumene hydroperoxide to separate it into a concentrate containing cumene hydroperoxide and a distillate. The reaction mixture is continuously distilled so that the ratio of the flow rate of the distillate to the flow rate of the reaction mixture to be distilled is 0.037 to 0.13. The epoxidation step involves obtaining a reaction mixture containing propylene oxide and cumyl alcohol by contacting the concentrate with propylene in the presence of a catalyst in one or more reactors to cause a reaction between propylene and cumene hydroperoxide in the concentrate, in which the outlet temperature of the final reactor is adjusted to 115 C. or more and less than 140 C.

The present invention relates to nebivolol synthesis method and intermediate compound thereof. Specifically, the present invention relates to a method for synthesizing nebivolol, intermediate compound thereof, and a method for preparing the intermediate compound.