4-Bed Molecular Sieve CO2 Scrubber

Spacecraft cabins have no atmosphere to vent CO2 into passively, so life support hardware like the ISS's 4-bed molecular sieve does the job in hardware: two zeolite beds alternate between adsorbing cabin CO2 and being heated and vented to vacuum to purge what they captured, so one bed is always scrubbing while its twin regenerates. This simulator drives a real Langmuir-kinetics adsorption/desorption model for both beds plus a live cabin CO2 mass balance driven by crew metabolic production, so you can watch what happens to cabin ppCO2 when the bed-switch timing, regeneration temperature, or crew load change — including what happens if the automatic sequencer is turned off and a bed is left to saturate.