Process for making unsaturated hydrocarbons using microchannel process technology

A process for converting a feed composition comprising one or more hydrocarbons to a product comprising one or more unsaturated hydrocarbons, the process comprising:

• flowing the feed composition and steam in contact with each other in a microchannel reactor at a temperature in the range from about 200° C. to about 1200° C. to convert the feed composition to the product, the process being characterized by the absence of catalyst for converting the one or more hydrocarbons to one or more unsaturated hydrocarbons;
• with the proviso that the microchannel reactor optionally further comprises one or more materials that function as a catalyst for a reaction other than the conversion of the one or more hydrocarbons to the one or more unsaturated hydrocarbons, provided such materials do not increase the conversion of the one or more hydrocarbons to the one or more unsaturated hydrocarbons by more than about 10% of what the conversion would be if such materials were not present.