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 work-up, to (a).
Abstract:
The present invention relates to a process for preparing an olefin oxide from a reaction mixture stream in an epoxidation reactor R, wherein R contains z active reaction tubes T(i) arranged in parallel, z≥2, i=1 . . . z, wherein each T(i) comprises a reaction zone Z(i) comprising a heterogeneous epoxidation catalyst, said reaction mixture stream comprising x components C(j), x≥3, j=1 . . . x, the process comprising (i) providing m educt streams E(k), m≥1, k=1 . . . m, wherein each E(k) exhibits a mass flow rate FE(k) and comprises y components C(j), y=1 . . . x, wherein a given component C(j) is contained in at least one E(k); (ii) dividing each E(k) into n educt substreams S(k,i), n≤z, each S(k,i) exhibiting a mass flow rate Fs(k,i), wherein to at least one E(k), the inequality (1) applies: Formulas (1), (2), (3), (iii) providing n reaction mixtures streams M(i) comprising the x components C(j), said providing comprising, for each i, either combining and admixing the n educt substreams S(k,i) obtaining the n reaction mixtures M(i) if m>1, or passing on the n educt substreams S(k,i) as the n reaction mixtures M(i) if m=1; (iv) feeding each M(i) obtained according to (iii) into Z(i) and contacting each M(i) in Z(i) with the epoxidation catalyst under epoxidation reaction conditions; wherein the x components C(j) comprise hydrogen peroxide, an organic solvent, and the olefin. The present invention further relates to an olefin oxide obtained or obtainable from said process.
Abstract:
The present invention relates to a specific continuous process for preparing a zeolitic material having a framework structure type selected from the group consisting of MFI, MEL, IMF, SVY, FER, SVR, and intergrowth structures of two or more thereof, preferably an MFI- and/or MEL-type framework structure, comprising Si, Ti, and O, and to a zeolitic material as obtainable and/or obtained according to said process. Further, the present invention relates to a process for preparing a molding, and to a molding obtainable and/or obtained according to said process. Yet further, the present invention relates to a use of said zeolitic material and molding.
Abstract:
A process for preparing a molding comprising zinc and a titanium-containing zeolitic material having framework type MWW, comprising (i) providing a molding comprising a titanium-containing zeolitic material having framework type MWW; (ii) preparing an aqueous suspension comprising a zinc source and the molding comprising a titanium-containing zeolitic material having framework type MWW prepared in (i); (iii) heating the aqueous suspension prepared in (ii) under autogenous pressure to a temperature of the liquid phase of the aqueous suspension in the range of from 100 to 200° C., obtaining an aqueous suspension comprising a molding comprising zinc and a titanium-containing zeolitic material having framework type MWW; (iv) separating the molding comprising zinc and a titanium-containing zeolitic material having framework type MWW from the liquid phase of the suspension obtained in (iii).
Abstract:
A process for preparing ethene oxide comprising providing a liquid feed stream comprising ethene, hydrogen peroxide, and a solvent; passing the liquid feed stream into an epoxidation zone comprising a catalyst comprising a titanium zeolite comprising zinc and having framework type MWW, and subjecting the liquid feed stream to epoxidation reaction conditions in the epoxidation zone, obtaining a reaction mixture comprising ethene oxide, water, and the solvent; removing an effluent stream from the epoxidation zone, the effluent stream comprising ethene oxide, water and the solvent.
Abstract:
Use of an acid-treated titanium-containing zeolitic material having framework type MWW for preparing a composition having a relative plasticity of less than 1.
Abstract:
Disclosed herein is a process for purifying propylene oxide, including the steps of: (i) providing a stream S0 containing propylene oxide, acetonitrile, water, and an organic compound containing a carbonyl group —C(═O)—; and (ii) separating propylene oxide from the stream S0 by subjecting the stream S0 to distillation conditions in a distillation column to obtain a gaseous top stream S1c which is enriched in propylene oxide compared to the stream S0, a liquid bottoms stream S1a which is enriched in acetonitrile and water compared to the stream S0, and a side stream S1b containing propylene oxide which is enriched in the carbonyl compound compared to the stream S0.
Abstract:
The invention relates to process for the regeneration of a catalyst comprising a titanium containing zeolite as catalytically active material comprising a stage comprising introducing a feed stream comprising propene, hydrogen peroxide or a hydrogen peroxide source, and an organic solvent into a reactor containing a catalyst comprising the titanium containing zeolite, subjecting the feed stream in the reactor to epoxidation conditions in the presence of the catalyst, removing a product steam comprising propylene oxide and the organic solvent from the reactor, stopping introducing the feed stream, washing the catalyst with a liquid aqueous system and calcining the washed catalyst.
Abstract:
A method of preparing a compound of formula (IV) where R1 is alkyl of 1 to 4 carbon atoms, comprises reacting cyclohexene with hydrogen peroxide and an alcohol R1OH in the presence of a catalyst comprising a zeolite of framework structure MWW, wherein the framework of the zeolite comprises silicon, titanium, boron, oxygen and hydrogen.
Abstract:
A process for preparing a tin-containing zeolitic material having an MWW-type framework structure comprising providing a zeolitic material having an MWW-type framework structure having vacant tetrahedral framework sites, providing a tin-ion source in solid form, and incorporating tin into the zeolitic material via solid-state ion exchange.