Patent ID: 7388106
Filing Date: 2008-06-17
Classification: B01J,C07C

Abstract:
1. A process for preparing acrolein or acrylic acid or a mixture thereof from propane, comprising: A) feeding a reaction gas mixture input stream A which has been obtained by combining at least four different gaseous starting streams conducting the reaction gas mixture input stream A in reaction zone A through at least one catalyst bed, optionally with supply of further gas streams, over which a product gas mixture stream A comprising propane and propylene is formed by partial heterogeneously catalyzed dehydrogenation of propane; conducting the product gas mixture stream A out of the first reaction zone A by discharge therefrom; dividing the product gas mixture stream A into two product gas mixture A substreams recycling product gas mixture A substream optionally conducting product gas mixture A substream B) conducting product gas mixture stream A substream conducting product gas mixture stream B out of reaction zone B into a second separating zone B; removing target product present in product gas mixture stream B and, from the remaining residual gas comprising unconverted propane molecular oxygen and optionally unconverted propylene; recycling at least a portion comprising unconverted propane, molecular oxygen and any unconverted propylene, in a second cycle gas method, into reaction zone A as the gaseous starting stream releasing the reaction gas mixture input stream A formed in this way into the inlet of the first reaction zone A, wherein gaseous starting streams