Method for the production of iso-olefines

A continuous process for preparing an 4-6C isoolefin involves cleaving a alkyl tert-alkyl ether and tertiary alcohol, in a gas phase over a solid catalyst, at 200-400[deg] C and at a pressure of 0.1-1.2 MPa, in a reactor equipped with a heating jacket and is heated with a liquid heat carrier. A continuous process for preparing an 4-6C isoolefin involves cleaving a alkyl tert-alkyl ether and tertiary alcohol compound of formula R 1-O-R 2 (I), in a gas phase over a solid catalyst, at 200-400[deg] C and at a pressure of 0.1-1.2 MPa, in a reactor equipped with a heating jacket and is heated with a liquid heat carrier. The cleavage is carried out in such a way that a temperature drop in the catalyst zone at any point in relation to the entrance temperature is less than 50[deg] C, where a reaction mixture in the reactor and the heat carrier in the jacket flow through the reactor in cocurrent; and a temperature difference of the heat carrier between a feed point to the reactor and an outlet from the reactor is adjusted to less than 40[deg] C. R 1tertiary 4-6C alkyl; R 2H or alkyl.