| 摘要 |
The invention relates to a method for producing butadiene from n-butane, comprising the steps of:A) providing an input gas flow a containing n-butane;B) feeding said input gas flow a containing n-butane into at least one first dehydrogenation zone and dehydrogenating n-butane in a non-oxidative catalytic manner, whereby a product gas flow b containing n-butane, 1-butene, 2-butene, butadiene, hydrogen, low-boiling secondary components, and optional steam is obtained;C) feeding the product gas flow b resulting from the non-oxidative catalytic dehydrogenation process and an oxygen-containing gas into at least one second dehydrogenation zone and oxidatively dehydrogenating 1-butene and 2-butene, whereby a product gas flow c containing n-butane, 2-butene, butadiene, hydrogen, low-boiling secondary components, and steam is obtained, said second product gas flow c having a higher butadiene content than product gas flow b;D) eliminating hydrogen, the low-boiling secondary components, and steam, whereby a Cproduct gas flow d essentially comprising n-butane, 2-butene, and butadiene is obtained;E) feeding the Cproduct gas flow d into a distillation zone and separating a butadiene/butane mixture as a valuable product flow e1 such that a flow e2 substantially comprising n-butane and 2-butene remains;F) redirecting flow e2 into the first dehydrogenation zone. |
