摘要:
A process for the long-term operation of a heterogeneously catalyzed gas phase partial oxidation of at least one organic compound over a catalyst bed, in which, in order to counteract the deactivation of the catalyst bed, the working pressure in the gas phase is increased during the operating time of the catalyst bed.
摘要:
A process for heterogeneously catalyzed gas phase partial oxidation of an organic starting compound over a fixed catalyst bed freshly installed into a reaction chamber, in which the reduction in the quality of the fixed catalyst bed is restored with increasing operating time by replacing a portion of the fixed catalyst bed by a replacement fixed catalyst bed part whose volume-specific activity is lower than the volume-specific activity of the replaced fixed catalyst bed part in its freshly installed state.
摘要:
The present invention relates to a process for preparing acrylic acid by two-stage heterogeneously catalyzed partial gas phase oxidation of propylene, in which the propylene source used is a preceding propane dehydrogenation and in which the first oxidation stage is operated with restricted propylene conversion, and unconverted propane and propylene present in the product gas mixture of the second partial oxidation stage are recycled substantially into the preceding propane dehydrogenation.
摘要:
In a process for heterogeneously catalyzed partial gas phase oxidation of propene to acrolein, the starting reaction gas mixture is oxidized at a propene loading of
摘要:
A shell which encloses an interior and has at least one first orifice for feeding at least one gas stream into the interior and at least one second orifice for withdrawing a gas stream fed to the interior beforehand via the at least one first orifice from the interior, the surface of the shell, on its side in contact with the interior, being manufactured at least partly, in a layer thickness of at least 1 mm, from a steel which has a specific elemental composition, and in the interior, a process for continuous heterogeneously catalyzed partial dehydrogenation of at least one hydrocarbon to be dehydrogenated is carried out in a reactor which is manufactured from the steel on its side in contact with the reaction gas.
摘要:
A process for preparing an organic target compound by heterogeneously catalyzed gas phase partial oxidation of an organic precursor compound with molecular oxygen in two oxidation reactor lines operated in parallel and removal of the target compound from the mixture of the product gas streams in a workup line, wherein the catalysts charge of one of the oxidation lines comprises a portion of catalyst over which the heterogeneously catalyzed gas phase partial oxidation has already been carried out for longer than over the portions of catalyst of the catalyst charge of the other oxidation reactor line.
摘要:
A process for heterogeneously catalyzed partial gas phase oxidation of propylene to acrylic acid, in which the starting reaction gas mixture comprises cyclopropane as an impurity and the acrylic acid, after conversion from the product gas mixture into the condensed phase, is removed with the aid of a crystallative removal.
摘要:
A process for preparing acrolein or acrylic acid or a mixture thereof as the target product from propane, in which propane is partially dehydrogenated under heterogeneous catalysis in a reaction zone A, molecular hydrogen formed is at least partly combusted to water, any water present in the product gas A formed in reaction zone A is removed therefrom and product gas A is otherwise used to charge a reaction zone B in which propylene formed in reaction zone A is partially oxidized in the presence of remaining propane to give the target product. The target product is removed from the product gas B formed in reaction zone B and propane present in the remaining residual gas is absorbed therefrom into a solvent and, after release from the absorbate, recycled into reaction zone A.
摘要:
A process for making acrylic acid from acrolein; a process for making methacrylic acid from methacrolein; and a process for making acrylic acid from propane.
摘要:
A process for removing methacrolein from liquid phase P comprising acrylic acid as a main constituent and target product, and methacrolein as a secondary component in which the removal is effected by crystallization, the acrylic acid accumulating in the crystals formed and the methacrolein in the remaining mother liquor.