Prior to the transient experiments, steady-state experiments are performed in order to identify FT-like conditions under which certain degree of chain-growth is achieved, while the formation of significant amounts of liquid products can be neglected. The reactor effluent was analyzed by GC, with respect to all gaseous compounds, including all hydrocarbons up to a carbon number of 6. The gas composition measured after 4 h time on stream (TOS) was used as reference point to ensure comparability. The experiments under FT-like conditions were carried out in a separate test plant with a similar reactor setup, but with additional hot and cold traps to ensure absence of condensed liquid hydrocarbons.