A process for preparing hydroformylation products of olefins having from 2 to
8
carbon atoms comprises
- a) feeding a hydrocarbon feedstock into a cracking/dehydrogenation zone
and subjecting it to thermal and/or catalytic cracking and/or dehydrogenation to
give an olefin-containing cracker gas,
- b) subjecting the cracker gas or fractions thereof to a fractionation
to give at least one Ci-olefin-enriched hydrocarbon stream and at least
one Ci-olefin-depleted hydrocarbon stream,
- c) feeding the Ci-olefin-enriched hydrocarbon stream together
with carbon monoxide and hydrogen into a hydroformylation zone and reacting it
in the presence of a hydroformylation catalyst,
- d) separating a stream consisting essentially of unreacted Ci-olefin
and saturated Ci-hydrocarbon from the output from the hydroformylation zone,
- e) recirculating at least part of the stream consisting essentially
of unreacted Ci-olefin and saturated Ci-hydrocarbon to step
b), where i is an integer from to 8.
The proposed coupling of the hydroformylation with, for example, a steam cracker
allows complete hydroformylation of the olefins produced without olefin losses
via the waste gas.
