C2-C30-alkanes are dehydrogenated in a process in which
(i) ethylbenzene is dehydrogenated to styrene in a first part process
to give a hydrogen-containing offgas stream, and
(ii) one or more C2-C30-alkanes are dehydrogenated
in the presence of a heterogeneous catalyst in one or more reaction zones in a
second part process to give the corresponding olefins, with a hydrogen-containing
gas stream being mixed into the reaction gas mixture of the dehydrogenation in
at least one reaction zone,
wherein at least part of the hydrogen-containing offgas stream obtained in
the dehydrogenation of ethylbenzene is mixed into the reaction gas mixture of the
alkane dehydrogenation.
