Abstract: A continuous process for preparing propylene oxide proceeds by (a) reacting propene with hydrogen peroxide in a reaction apparatus in the presence acetonitrile as solvent, obtaining a stream S0 containing propylene oxide, acetonitrile, water, at least one further component B; (b) separating propylene oxide from S0, obtaining stream S1 containing acetonitrile, water and B; (c) dividing S1 into streams S2 and S3; (d) subjects S3 to vapor-liquid fractionation in a first fractionation unit, obtaining vapor fraction stream S4a being depleted, relative to S3, of at least one of B and obtaining liquid bottoms stream S4b, and subjecting at least part of vapor fraction stream S4a to vapor-liquid fractionation in a second fractionation unit, obtaining vapor fraction stream S4c and liquid bottoms stream S4 being depleted, relative to S4a, of at least one of B; (e) recycling at least a portion of S4 to (a).

Abstract: A continuous process for preparing propylene oxide proceeds by (a) reacting propene with hydrogen peroxide in a reaction apparatus in the presence acetonitrile as solvent, obtaining a stream S0 containg propylene oxide, acetonitrile, water, at least one further componen B; (b) separating propylene oxide from S0, obtaining stream S1 containing acetonitrile, water and B; (c) dividing Sa into streams S2 and S3; (d) subjects S3 to vapor-liquid fractionation in a first fractionation unit, obtaining vapor fraction stream S4a being depleted, relative to S3, of at least one of B and obtaining liquid bottoms stream S4b, and subjecting at least part of vapor fraction stream S4a to vapor-liquid fractionation in a second fractionation unit, obtaining vapor fraction stream S4c and liquid bottoms stream S4 being depleted, relative to S4a, of at least one of B; (e) recycling at least a portion of S4 to (a).

Abstract: The present invention relates to a process for the regeneration of a catalyst comprising a titanium-containing zeolite, said catalyst having been used in a process for the preparation of an olefin oxide and having phosphate deposited thereon, said process for the regeneration comprising the steps: (a) separating the reaction mixture from the catalyst, (b) washing the catalyst obtained from (a) with liquid aqueous system; (c) optionally drying the catalyst obtained from (b) in a gas stream comprising an inert gas at a temperature of less than 300° C.; (d) calcining the catalyst obtained from (c) in a gas stream comprising oxygen at a temperature of at least 300° C.

Abstract: A continuous process for the preparation of propylene oxide, comprising (a) reacting propene, optionally admixed with propane, with hydrogen peroxide in a reaction apparatus in the presence of acetonitrile as solvent, obtaining a stream S0 containing propylene oxide, acetonitrile, water, at least one further component B, optionally propene and optionally propane, wherein the normal boiling point of the at least one component B is higher than the normal boiling point of acetonitrile and wherein the decadic logarithm of the octanol-water partition coefficient (log Kow) of the at least one component B is greater than zero; (b) separating propylene oxide from S0, obtaining a stream S1 containing acetonitrile, water and the at least one further component B; (c) dividing S1 into two streams S2 and S3; (d) subjecting S3 to a vapor-liquid fractionation in a fractionation unit, obtaining a vapor fraction stream S4 being depleted of the at least one component B; (e) recycling at least a portion of S4, optionally after

Abstract: A continuous process for the preparation of propylene oxide, comprising (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 wherein the molar ratio of potassium relative to phosphorus in the at least one potassium salt of a phosphorus oxyacid is in the range of from 0.6 to 1.

Abstract: A continuous process for the preparation of propylene oxide, comprising (i) providing a liquid feed stream comprising propene, hydrogen peroxide, acetonitrile, water, dissolved potassium dihydrogen phosphate, and optionally propane; (ii) passing the liquid feed stream provided in (i) into an epoxidation reactor comprising a catalyst comprising a titanium zeolite of structure type MWW, and subjecting the liquid feed stream to epoxidation reaction conditions; (iii) removing an effluent stream from the epoxidation reactor; wherein the concentration of the dissolved potassium dihydrogen phosphate in the liquid feed stream is at least 10% of the solubility limit of the potassium dihydrogen phosphate in the liquid feed stream.

Abstract: A continuous process for the preparation of propylene oxide, comprising (a) reacting propene, optionally admixed with propane, with hydrogen peroxide in a reaction apparatus in the presence of acetonitrile as solvent, obtaining a stream S0 containing propylene oxide, acetonitrile, water, at least one further component B, optionally propene and optionally propane, wherein the normal boiling point of the at least one component B is higher than the normal boiling point of acetonitrile and wherein the decadic logarithm of the octanol-water partition coefficient (log Kow) of the at least one component B is greater than zero; (b) separating propylene oxide from S0, obtaining a stream S1 containing acetonitrile, water and the at least one further component B; (c) dividing S1 into two streams S2 and S3; (d) subjecting S3 to a vapor-liquid fractionation in a fractionation unit, obtaining a vapor fraction stream S4 being depleted of the at least one component B; (e) recycling at least a portion of S4, optionally after

Abstract: The present invention relates to a process for the regeneration of a catalyst comprising a titanium-containing zeolite, said catalyst having been used in a process for the preparation of an olefin oxide and having phosphate deposited thereon, said process for the regeneration comprising the steps: (a) separating the reaction mixture from the catalyst, (b) washing the catalyst obtained from (a) with liquid aqueous system; (c) optionally drying the catalyst obtained from (b) in a gas stream comprising an inert gas at a temperature of less than 300° C.; (d) calcining the catalyst obtained from (c) in a gas stream comprising oxygen at a temperature of at least 300° C.

Abstract: A continuous process for the preparation of propylene oxide, comprising (i) providing a liquid feed stream comprising propene, hydrogen peroxide, acetonitrile, water, dissolved potassium dihydrogen phosphate, and optionally propane; (ii) passing the liquid feed stream provided in (i) into an epoxidation reactor comprising a catalyst comprising a titanium zeolite of structure type MWW, and subjecting the liquid feed stream to epoxidation reaction conditions; (iii) removing an effluent stream from the epoxidation reactor; wherein the concentration of the dissolved potassium dihydrogen phosphate in the liquid feed stream is at least 10% of the solubility limit of the potassium dihydrogen phosphate in the liquid feed stream.

Abstract: A continuous process for the preparation of propylene oxide, comprising (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 wherein the molar ratio of potassium relative to phosphorus in the at least one potassium salt of a phosphorus oxyacid is in the range of from 0.6 to 1.

Abstract: A continuous process for the preparation of propylene oxide, comprising (a) reacting propene, optionally admixed with propane, with hydrogen peroxide in a reaction apparatus in the presence of acetonitrile as solvent, obtaining a stream S0 containing propylene oxide, acetonitrile, water, at least one further component B, optionally propene and optionally propane, wherein the normal boiling point of the at least one component B is higher than the normal boiling point of acetonitrile and wherein the decadic logarithm of the octanol-water partition coefficient (log Kow) of the at least one component B is greater than zero; (b) separating propylene oxide from S0, obtaining a stream S1 containing acetonitrile, water and the at least one further component B; (c) dividing S1 into two streams S2 and S3; (d) subjecting S3 to a vapor-liquid fractionation in a fractionation unit, obtaining a vapor fraction stream S4 being depleted of the at least one component B; (e) recycling at least a portion of S4, optionally after

Abstract: The present invention relates to a micropowder, wherein the particles of the micropowder have a Dv10 value of at least 2 micrometer and the micropowder comprises mesopores which have an average pore diameter in the range of from 2 to 50 nm and comprise, based on the weight of the micropowder, at least 95 weight-% of a microporous aluminum-free zeolitic material of structure type MWW containing titanium and zinc.

Abstract: The present invention relates to a micropowder, wherein the particles of the micropowder have a Dv10 value of at least 2 micrometer and the micropowder comprises mesopores which have an average pore diameter in the range of from 2 to 50 nm and comprise, based on the weight of the micropowder, at least 95 weight-% of a microporous aluminum-free zeolitic material of structure type MWW containing titanium and zinc.

Abstract: A process for producing propylene oxide comprising reacting propene with hydrogen peroxide in the presence of a catalyst to give a mixture (G1) comprising propylene oxide, unreacted propene, and oxygen; separating propylene oxide from mixture (G1) to give a mixture (GII) comprising propene and oxygen; and adding hydrogen to mixture (GII) and reducing the oxygen comprised in mixture (GII) at least partially by reaction with hydrogen in the presence of a catalyst comprising copper in elemental and/or oxidic form on a support, wherein copper is present on the support in an amount of 30 to 80 wt.-% based on the whole catalyst and calculated as CuO.

Abstract: A continuous process for the production of propylene oxide comprising reacting propene with hydrogen peroxide in methanolic solution in the presence of a titanium silicalite-1 catalyst to obtain propylene oxide, wherein a reaction feed comprising propene, methanol and hydrogen peroxide is introduced into a reactor, said reaction feed containing potassium cations and phosphorus in the form of anions of at least one phosphorus oxyacid.

Abstract: The present invention relates to a micropowder, wherein the particles of the micropowder have a Dv10 value of at least 2 micrometer and the micropowder comprises mesopores which have an average pore diameter in the range of from 2 to 50 nm and comprise, based on the weight of the micropowder, at least 95 weight-% of a microporous aluminum-free zeolitic material of structure type MWW containing titanium and zinc.

Abstract: A method for separating acetonitrile from water, comprising (i) providing a stream S1 containing at least 95 wt.-%, based on the total weight of S1, acetonitrile and water, wherein the weight ratio of acetonitrile: water is greater than 1; (ii) adding a stream P, comprising at least 95 wt.-% C3, based on the total weight of stream P, to S1 to obtain a mixed stream S2, C3 being propene optionally admixed with propane with a minimum weight ratio of propene: propane of 7:3; (iii) subjecting S2 to a temperature of 92° C. at most and a pressure of at least 10 bar, obtaining a first liquid phase L1 essentially consisting of C3, acetonitrile, and water, and a second liquid phase L2 essentially consisting of water and acetonitrile wherein the weight ratio of acetonitrile: water in L2 is less than 1; (iv) separating L1 from L2.

Abstract: The present invention relates to a micropowder, wherein the particles of the micropowder have a Dv10 value of at least 2 micrometer and the micropowder comprises mesopores which have an average pore diameter in the range of from 2 to 50 nm and comprise, based on the weight of the micropowder, at least 95 weight-% of a microporous aluminum-free zeolitic material of structure type MWW containing titanium and zinc.

Abstract: A continuous process for the production of propylene oxide comprising reacting propene with hydrogen peroxide in methanolic solution in the presence of a titanium silicalite-1 catalyst to obtain propylene oxide, wherein a reaction feed comprising propene, methanol and hydrogen peroxide is introduced into a reactor, said reaction feed containing potassium cations and phosphorus in the form of anions of at least one phosphorus oxyacid.

Abstract: A process for producing propylene oxide comprising reacting propene with hydrogen peroxide in the presence of a catalyst to give a mixture (G1) comprising propylene oxide, unreacted propene, and oxygen; separating propylene oxide from mixture (G1) to give a mixture (GII) comprising propene and oxygen; and adding hydrogen to mixture (GII) and reducing the oxygen comprised in mixture (GII) at least partially by reaction with hydrogen in the presence of a catalyst comprising copper in elemental and/or oxidic form on a support, wherein copper is present on the support in an amount of 30 to 80 wt.-% based on the whole catalyst and calculated as CuO.