| 摘要 |
<p>Acrolein and/or acrylic acid is prepared by feeding to a first reaction zone A at least two gaseous, propane-containing feed streams comprising fresh propane, and in reaction zone A, subjecting their propane fed to a heterogeneously catalyzed dehydrogenation to obtain a product gas mixture A comprising propane and propylene. Preparation of acrolein and/or acrylic acid involves feeding to a first reaction zone A at least two gaseous, propane-containing feed streams having fresh propane and in reaction zone A, subjecting their propane fed in this way to a heterogeneously catalyzed dehydrogenation to obtains a product gas mixture A comprising propane and propylene; conducting product gas mixture A out of reaction zone A and in a first separation zone A, removing a portion of the constituents other than propane and propylene in product gas mixture A and using remaining product gas mixture A' comprising propane and propylene; in a second reaction zone B to charge an oxidation reactor and, in the oxidation reaction, subjecting the propylene present in product gas mixture A' to a catalyst gas phase partial oxidation with molecular oxygen to give a product gas mixture B having acrolein or acrylic acid as the target product and also excess molecular oxygen; and conducting product gas mixture b out of reaction zone B and in a second separation zone, removing target product present in product gas mixture B, and of the remaining residual gas having unconverted propane, molecular oxygen and any unconverted propylene as one of the two-propane-containing feed streams into reaction zone A, where this recycling into he reaction zone A along the reaction path of the catalyzed dehydrogenation of propane in reaction zone A is effected such that at the feed point, >=5 mol.% of the propane fed to reaction zone A via the other feed streams has already been converted under dehydrogenating conditions in reaction zone A.</p> |
