Abstract: The invention relates to a method for continuously returning an olefin which has not been reacted with hydroperoxide in order to form oxiranes during the epoxidation of olefins. Said olefin is contained in the flow of waste gas which is produced during epoxidation. Said method is characterised by the following steps: (i) compressing and cooling the flow of waste gas, (ii) separating the olefin from the flow of waste gas obtained in step (i) by distillation,(iii) epoxidating the olefin separated in (ii) with hydroperoxide.

Abstract: The invention relates to a process for obtaining a pure aliphatic dialdehyde monoacetal by reaction of the corresponding aliphatic dialdehyde or a precursor of the corresponding aliphatic dialdehyde with one or more aliphatic mono- or polyhydric alcohols while distillatively removing water to obtain a reaction mixture which is separated distillatively, which comprises carrying out the distillative separation continuously in a dividing wall column to obtain pure aliphatic dialdehyde monoacetal as a sidestream from the dividing wall column, or in two distillation columns to obtain crude aliphatic dialdehyde monoacetal as a sidestream in the first distillation column, feed the crude aliphatic dialdehyde monoacetal to the second distillation column and obtain pure aliphatic dialdehyde monoacetal as the sidestream from the second distillation column.

Abstract: A process is described for selectively hydrogenating citronellal to citronellol in which a liquid phase, in which the citronellal is dissolved and particles of a catalyst are suspended which is capable of preferentially hydrogenating carbon-oxygen double bonds over carbon—carbon double bonds, is conducted through a device which inhibits the transport of the catalyst particles in the presence of a hydrogen-containing gas.

Abstract: Process for the continuous preparation of propylene glycols, which comprises the steps (i) to (ii): (i) reacting propylene with hydrogen peroxide to form propylene oxide and give propylene glycols as by-products, (ii) reacting the propylene oxide obtained in step (i) with water to give propylene glycols, (iii) separating off the propylene glycols obtained in steps (i) and (ii).

Abstract: Continuously operated process for the intermediate isolation of the oxirane formed by reaction of a hydroperoxide with an organic compound in the oxirane synthesis, wherein the product mixture formed in the synthesis is fractionated in a dividing wall column to give a low-boiling fraction, an intermediate-boiling fraction and a high-boiling fraction and the oxirane is taken off in the intermediate-boiling fraction at the side offtake and the hydroperoxide is taken off in the high-boiling fraction at the bottom of the column.

Abstract: The present invention relates to the manufacture of solid materials or shaped bodies containing at least one zeolite and being at least partly crystalline. Furthermore, the present invention relates to the solid materials or shaped bodies as such and to the use of these materials for reactions of compounds having at least one C—C double bond with at least one hydroperoxide. Specifically, the present invention relates to a process for the manufacture of a solid material containing at least one zeolite and being at least partly crystalline, wherein the synthesis of the said solid material involves at least one partial step of contacting at least one transition metal oxide source with at least one epoxide or hydrolysate thereof prior to or during the at least partial crystallization of said solid material.

Abstract: A method of separating propylene oxide from a mixture (M) comprising 5 to 50 percent by weight propylene oxide and 50 to 85 percent by weight methanol, said method comprising (i) introducing said mixture (M) into an extractive distillation column; (ii) additionally introducing a polar solvent into said extractive distillation column; (iii) distilling propylene oxide overhead from said extractive distillation column at a bottoms temperature of from 40 to 70° C. and at a pressure of from 300 to 750 mbar.

Abstract: A method of separating propylene oxide from a mixture (M) comprising propylene oxide and methanol, said method comprising (i) introducing said mixture (M) into an extractive distillation column; (ii) additionally introducing an extracting solvent into said extractive distillation column; (iii) distilling propylene oxide overhead from said extractive distillation column as top stream; (iv) withdrawing a bottoms stream from said extractive distillation column; (v) compressing the top stream obtained overhead in (iii) by means of at least one compressor to give a compressed vapor.

Abstract: Process for the continuously operated purification by distillation of the methanol used as solvent in the synthesis of propylene oxide by reaction of a hydroperoxide with propylene, with the methoxypropanols being separated off simultaneously, wherein the solvent mixture obtained in the synthesis is separated in a dividing wall column into a low-boiling fraction comprising methanol, an intermediate-boiling fraction comprising the methoxypropanols as azeotrope with water and a high-boiling fraction comprising water and propylene glycol.

Abstract: Continuously operated process for the purification by distillation of the methanol used as solvent in the synthesis of propylene oxide by reaction of a hydroperoxide with propylene, with the methoxypropanols, as azcotrope with water, and the low boilers and high boilers simultaneously being separated off, wherein the solvent mixture obtained in the synthesis is fractionated in a dividing wall column.

Abstract: The invention relates to a continuously operated process for the purification by distillation of the 1,2-propylene glycol formed as by-product in the synthesis of propylene oxide, wherein the mixture formed in the synthesis which contains the 1,2-propylene glycol is separated in a dividing wall column into low-, intermediate, and high-boiling fractions and the 1,2-propylene glycol is taken off as intermediate boiler at the side offtake of the column.

Abstract: The present invention relates to a method of separating an olefin from a gas stream, said gas stream comprising the olefin and at least one other component, said method comprising (i) compressing and cooling the gas stream; (ii) separating the olefin from the gas stream by absorbing the olefin in an absorbent; (iii) separating the olefin from the absorbent by desorption; wherein compressing or cooling or compressing and cooling in (i) is carried out at least twice.

Abstract: Process for the continuously operated distillation of the solvent used in the synthesis of an oxirane by reaction of a hydroperoxide with an organic compound, wherein the mixture comprising the solvent which is obtained in the synthesis and subsequent work-up is separated in a dividing wall column into a low-boiling fraction, an intermediate-boiling fraction and a high-boiling fraction and the solvent is taken off as intermediate-boiling fraction from the side offtake of the column.

Abstract: The invention relates to a continuously operated process for the purification by distillation of the oxirane formed in the oxirane synthesis by reaction of a hydroperoxide with an organic compound, wherein the crude oxirane is separated in a dividing wall column into low-, intermediate- and high-boiling fractions and the oxirane is taken off as intermediate boiler at the side offtake in a concentration of at least 99.9%.

Abstract: The present invention relates to a continuous process for the selective hydrogenation of olefinically unsaturated carbonyl compounds to give unsaturated alcohols in particular of citral to give a mixture of geraniol and nerol, in a reactor containing a liquid phase, in which at least one catalyst is suspended, and which can additionally contain a gas phase, wherein the liquid phase and, if present, the gas phase are passed through a device in the reactor having openings or channels.

Abstract: The present invention relates to the manufacture of solid materials or shaped bodies containing at least one zeolite and being at least partly crystalline. Furthermore, the present invention relates to the solid materials or shaped bodies as such and to the use of these materials for reactions of compounds having at least one C—C double bond with at least one hydroperoxide. Specifically, the present invention relates to a process for the manufacture of a solid material containing at least one zeolite and being at least partly crystalline, wherein the synthesis of the said solid material involves at least one partial step of contacting at least one transition metal oxide source with at least one epoxide or hydrolysate thereof prior to or during the at least partial crystallization of said solid material.

Abstract: The present invention relates to a process for treating a solid material containing at least one zeolite and being at least partly crystalline or treating a shaped body obtained from said solid material wherein said solid material or shaped body is brought in contact with a composition containing water after at least one of the following steps of an integrated process for producing a solid material or a shaped body containing at least one zeolite: (i) after step (II) of separating the at least partly crystalline solid material from its mother liquor or (ii) after step (S) of shaping said solid material into a shaped body or (iii) after a step (C) of calcining said solid material or said shaped body. The present invention furthermore relates to the solid material obtainable by the inventive process and the shaped body obtainable by the inventive process.

Abstract: The present invention relates to the manufacture of solid materials or shaped bodies containing at least one zeolite and being at least partly crystalline. Furthermore, the present invention relates to the solid materials or shaped bodies as such and to the use of these materials for reactions of compounds having at least one C—C double bond with at least one hydroperoxide. Specifically, the present invention relates to a process for the manufacture of a solid material containing at least one zeolite and being at least partly crystalline, wherein the synthesis of the said solid material involves at least one partial step of contacting at least one transition metal oxide source with at least one epoxide or hydrolysate thereof prior to or during the at least partial crystallization of said solid material.

Abstract: The present invention relates to a process for the preparation of tetrahydrogeraniol, wherein the product mixtures and distillation residues from linalool, citronellal, citronellol or geraniol/nerol synthesis are fed directly to catalytic hydrogenation.

Abstract: The present invention relates to a continuous process for the preparation of cinnamaldehyde or cinnamaldehyde derivatives by continuous reaction of benzaldehyde derivatives with alkanals in the presence of bases and optionally subsequent continuous hydrogenation in a circulation reactor in the presence of a suspension catalyst and hydrogen to give dihydrocinnamaldehyde derivatives.