Fischer-Tropsch synthesis (FTS) is a demanding fixed-bed evaluation: the reaction is exothermic, the product slate ranges from methane to waxes, and the carbon number distribution itself is a key result. The rig and the analysis plan must be designed for that breadth.
Pressure-rated tubing reactors with small catalyst charges to limit exotherm; precise syngas metering (H2/CO ratio is a selectivity variable); good temperature control with bed thermocouples; and a hot trap for waxes plus cold traps for condensables before the gas analyzer. Pressure and temperature set the chain-growth probability, so log both continuously.
The gas stream carries C1-C4 hydrocarbons to online GC; the wax and liquid fractions are recovered periodically and analyzed off-line by GC with simulated distillation. The full slate, gas + liquids + waxes, is the deliverable, reporting only methane selectivity describes a failed FTS campaign.
CO conversion, CH4 selectivity, chain-growth probability alpha from the Anderson-Schulz-Flory fit, and productivity per gram of catalyst. Alpha tells you whether the catalyst is doing FTS or methanation; track it as conditions change.
Run-in matters: FTS activity evolves during the first hours as the catalyst carburizes or restructures. Define a stabilization period and reach steady state before sampling, and confirm steady state by repeated mass balances, not by the clock.
See catalytic reaction systems and solutions for high-pressure FTS evaluation setups.
