Process for preparing delta-valerolactone in the gas phase

A process for preparing a delta-valerolactone proceeding from 1,5 pentanediol, comprising:

• a) evaporating the 1,5-pentanediol in an inert gas stream;
• b) passing the inert gas stream comprising 1,5-pentanediol through a catalyst bed comprising at least two different catalysts, to obtain a gas mixture;
• and
• (c) condensing a reaction product out of the gas mixture obtained in b),
• wherein the catalysts comprise the at least one of an element and a compound selected from the group consisting of elements of periods 7 to 12 of the Periodic Table, and
• wherein the catalysts have a layer structure such that the inert gas stream comprising 1,5-pentanediol flows first through the catalyst which exhibits the highest conversion and selectivity for preparing the delta-valerolactone proceeding from 1,5-pentanediol at a given catalyst bed inlet temperature, and then through the catalyst which exhibits the highest conversion and selectivity for preparing the delta-valerolactone proceeding from 1,5-pentanediol at a lower temperature.