Method for the catalytic decomposition of N2O

A process for the catalytic decomposition of N2O in a gas mixture obtained in the preparation of nitric acid by catalytic oxidation of ammonia, where the N2O is decomposed catalytically over a catalyst for the decomposition of N2O, wherein the hot gas mixture obtained from the catalytic oxidation of ammonia is brought into contact with the catalyst for the decomposition of N2O prior to subsequent cooling, wherein the residence time over the catalyst for the decomposition of N2O is less than 0.05 s wherein the process is carried out in a reactor which contains a noble metal gauze catalyst and a heat exchanger in that order in the direction of flow and the catalyst for the decomposition of N2O is located between the noble metal gauze catalyst and the heat exchanger, wherein the catalyst for the decomposition of N2O is installed as a fixed bed having a height of from 5-10 cm.