| 摘要 |
The invention relates to a method for the oxidative dehydrogenation of n-butenes to form butadiene, said method comprising two or more production steps (i) and at least one regeneration step (ii). In said method: (i) in a production step a starting gas mixture containing n-butene is mixed with a gas containing oxygen and the mixed gas is brought into contact with a multi-metal-oxide catalyst containing at least molybdenum and another metal in a fixed-bed reactor, at a temperature of between 220 and 490 °C. A product gas mixture at least containing butadiene, oxygen and steam is thus obtained at the outlet of the fixed-bed reactor; (ii) in a regeneration step, to regenerate the multi-metal oxide catalyst, a regeneration gas mixture containing oxygen is passed over the catalyst fixed bed at a temperature between 200 and 450 °C and the carbon deposited on the catalyst is burnt off. A regeneration step (ii) is carried out between two production steps (i), the oxygen content of the product gas mixture at the outlet of the fixed-bed reactor is at least 5 vol. % and the duration of a production step (i) is less than 1,000 h. |
