Patent ID: 7495138
Filing Date: 2009-02-24
Classification: C07C

Abstract:
1. A process for preparing butadiene from n-butane, comprising the steps of A) providing a feed gas stream (a) comprising n-butane; B) feeding said feed gas stream (a) into at least one first dehydrogenation zone and nonoxidatively, catalytically dehydrogenating n-butane to obtain a gas stream (b) comprising n-butane, 1-butene, 2-butene, butadiene, and hydrogen, and optionally further comprising carbon oxides and/or steam and/or inert gases; C) feeding said gas stream (b) and an oxygenous gas into at least one second dehydrogenation zone and oxidatively dehydrogenating 1-butene and 2-butene to obtain a gas stream (c) comprising n-butane, butadiene, and hydrogen, and optionally further comprising carbon oxides and/or inert gases; D) compressing in at least one first compression stage and cooling said gas stream (c) to obtain at least one condensate stream (d E) separating said gas stream (d F) optionally compressing in at least one further compression stage and cooling said gas stream (e G) separating said gas stream (f