▎ 摘　　要

NOVELTY - Production of hydrogen, carbon and optionally hydrocarbons, such as 2C or more hydrocarbon(s), by catalytic non-oxidative decomposition of a reaction gas comprising a hydrocarbon or its mixture, such as saturated 1C or more hydrocarbon or its mixture, involves (i) supplying a catalyst composition comprising carbon catalyst(s) to a reaction zone, (ii) heating the catalyst composition in the reaction zone at a temperature of 500-1100° C by induction heating, (iii) activating the heated composition by contacting the composition with reaction gas comprising a hydrocarbon or its mixture, such as saturated 1C or more hydrocarbon or its mixture during an activation period of 5 hours or more, and (iv) performing catalytic non-oxidative decomposition of the reaction gas to obtain hydrogen, carbon, and optionally hydrocarbons, such as 2C or more hydrocarbon(s), by contacting the reaction gas with the heated and activated composition in the reaction zone during a suitable period of time. USE - Production of hydrogen, carbon and optionally hydrocarbons, such as 2C or more hydrocarbon(s). Uses include but are not limited to chemical industry, pharmaceutical industry, domestic heating application, and fuel in transportation application. ADVANTAGE - The method enables economical, efficient and environmentally-friendly production of hydrogen, carbon and optionally hydrocarbons, such as 2C or more hydrocarbon(s), with high selectivity, reduced energy consumption, smaller carbon footprint, and minimal production of carbon oxide. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: a spent catalyst; and use of the spent catalyst as carbon catalyst in catalytic non-oxidative hydrocarbon decomposition of hydrocarbons, such as saturated 1C or more hydrocarbons, into hydrogen and carbon, and optionally hydrocarbons, such as 2C or more hydrocarbon(s).