Fischer-Tropsch Synthesis: Matching the Catalyst to the Feedstock and the Reactor

Only three elements have been found suitable for the Fischer-Tropsch synthesis:  iron, cobalt and ruthenium.  However, for each of these elements a variety of catalyst formulations are possible.  It therefor becomes a problem of mating a catalyst formulation to the properties of the feedstock.  While any carbon containing feedstock can be used to generate a syngas, the impurity compounds and levels may vary with each feedstock as will the hydrogen/carbon monoxide ratio that is produced.  The adjustment of the hydrogen/carbon monoxide ratio to that needed for synthesis will define the reactors needed as well as the catalyst.  In addition, four reactor types have been utilized for Fischer-Tropsch synthesis:  fixed- and circulating-fluid bed, fixed bed and slurry reactor.  In addition small channel reactors are in the development stage and these offer attractive features.  The properties, both physical and chemical, must then be matched to those needed for each reactor type.