CO2 hydrogenation spans two flagship chemistries, methanol synthesis and Sabatier methanation, and both are standard fixed-bed evaluations. The rig must handle hydrogen at pressure, control temperature precisely and analyze conversion and selectivity continuously. Here is how the pieces fit.
Mass-flow controllers for CO2, H2 and diluent; a pressure-rated reactor in a precision furnace; a back-pressure regulator downstream; and online analysis by GC or methanizer-equipped detectors. Interlocks and venting for hydrogen are not optional accessories, they are the difference between a rig and a hazard.
Methanation is favored at higher temperatures with nickel catalysts; methanol needs lower windows with oxide catalysts, because methanol thermodynamics worsen as temperature climbs. Screen temperature in small steps, methanol selectivity can peak and fall within a 30-degree span.
Higher pressure helps methanol (fewer moles to more); methanation is less pressure-sensitive. H2/CO2 ratio steers selectivity, excess hydrogen suppresses CO via reverse water-gas shift and helps methanol; ratios near stoichiometric methanation (4:1) favor CH4. Space velocity sets single-pass conversion, keep it high enough to stay differential when comparing kinetics.
Baseline at reference conditions, then temperature scan, then pressure steps, then ratio sweep. Re-visit the baseline at the end to confirm the catalyst did not drift during the campaign, drift invalidates every scan taken in between.
Perfectlight's catalytic reaction systems cover pressurized fixed-bed evaluation; see catalysis solutions.
