Abstract:
A process for preparing formic acid by hydrogenation of carbon dioxide in the presence of a tertiary amine (I), a diamine (II), a polar solvent and a catalyst comprising gold at a pressure of from 0.2 to 30 MPa abs and a temperature of from 0 to 200°C, wherein the catalyst is a heterogeneous catalyst comprising gold.
Abstract:
The invention relates to a method for producing 4-pentenoic acid, at least comprising the oxidation of a mixture (G) containing 4-pentenal, 3-methyl-2-butanone and cyclopentene oxide and to the use of a mixture (G) containing 4-pentenal, 3-methyl-2-butanone and cyclopentene oxide for producing 4-pentenoic acid. The invention also relates to the mixture (G) which is obtained as an auxiliary product from the oxidation of cyclopentene to cyclopentanone by means of dinitrogen monoxide.
Abstract:
The invention relates to a method for producing at least one cyclic compound comprising Z cycles and between 7 and 16 C atoms with one carbonyl group, said method comprising at least the following steps: (a1) oxidation of a composition (A), at least containing one cyclic olefin with Z cycles and between 7 and 16 C atoms and at least two C-C double bonds, using dinitrogen monoxide, to obtain a composition (A1); (a2) isolation of the at least one cyclic olefin comprising Z cycles and between 7 and 16 C atoms with at least two C-C double bonds from the composition (A1) to obtain a composition (A2); and (b) distillatory treatment of the composition (A2) from step (a2) to obtain a composition (B) containing the at least one cyclic compound with Z cycles and between 7 and 16 C atoms with one carbonyl group and less than 1.0 wt. % of the at least one compound comprising Z-1 cycles and between 7 and 16 C atoms with at least one aldehyde group. According to the invention, Z can be 1, 2, 3 or 4.
Abstract:
The invention relates to a tube bundle reactor having a flat feed dome. Alternatively, the discharge dome can also be designed flat. The flat design reduces the reaction heat developing in the hood in reaction types that take place not only in the tube bundle (non-catalyzed reactions and reactions with homogenously distributed catalyst). Undesired reactions that already take place in the dome due to accumulated heat are thus heavily suppressed, whereby greater selectivity in temperature-sensitive reactions is achieved. Additionally, the temperature distribution within the domes can be precisely controlled. The tube bundle reactor comprises a tube bundle that has a feed end connected to a feed dome of the tube bundle reactor, wherein the feed dome is designed in a flat shape having a cross-sectional surface at the feed end and an inner volume, and the ratio of the inner volume to the cross-sectional surface is less than 0.35 m. The invention is furthermore implemented by a method for operating a tube bundle reactor, comprising: introducing a reactant mixture into a tube bundle and converting at least a portion of the reactant mixture into a product inside the tube bundle. The introduction step comprises: feeding the reactant mixture into an inner space of a feed dome of the tube bundle reactor and forwarding the reactant mixture into a feed end of the tube bundle in the form of a fluid flow. The fluid flow has a cross-sectional surface upon entering the feed end and the inner space of the feed dome through which the fluid flows has an inner volume; wherein the ratio of the inner volume to the cross-sectional surface is less than 0.35 m.
Abstract:
The invention relates to a method for obtaining cyclododecatriene (CDT) from a solution containing CDT and high-boiling components such as a deactivated catalyst and polymers. Said solution is supplied to a preheater and heated, and is then relaxed over a downstream pressure maintaining device, and the two-phase mixture obtained is supplied to a spiral tube evaporator where the CDT content of the liquid phase is reduced by partial evaporation and a gaseous product flow with an increased CDT concentration is derived.