Process for heat integration in the hydrogenation and distillation of C₃—C₂₀-aldehydes

摘要

The present invention relates to a process for heat integration in the preparation of saturated C3-C20-alcohols, in which a hydrogenation feed comprising at least one C3-C20-aldehyde is hydrogenated in the presence of a hydrogen-comprising gas in a hydrogenation zone and a discharge is taken off from the hydrogenation zone and subjected to distillation in at least one distillation column to give a fraction enriched in saturated C3-C20-alcohols.

主权项

1. A process for heat integration in the preparation of saturated C3-C20-alcohols, in which a hydrogenation feed comprising at least one C3-C20-aldehyde is hydrogenated in the presence of a hydrogen-comprising gas in a hydrogenation zone and a discharge is taken off from the hydrogenation zone and subjected to distillation in at least one distillation column to give a fraction which is enriched in saturated C3-C20-alcohols, wherein
a liquid stream S1) is taken off from the hydrogenation zone, heat is withdrawn from this stream and the stream is subsequently recirculated to the hydrogenation zone and/or a gaseous stream S2) is taken off at the top of at least one distillation column, heat is withdrawn from this stream and the stream is optionally then recirculated to the distillation,where the heat is withdrawn from the stream S1) and/or the stream S2) by indirect heat exchange and is transferred to a stream to be heated without the use of an auxiliary medium for heat transfer,wherein an aldehyde mixture comprising at least two C3-C20-aldehydes having the same number of carbon atoms is subjected to fractional distillation to give a fraction comprising the major part of one of the C3-C20-aldehydes and this fraction is used as hydrogenation feed, andwherein heat withdrawn from the stream S1) and/or the heat withdrawn from the stream S2) is used for heating the aldehyde mixture to be fractionally distilled.