It is said that NASA used 100-percent-Oxygen artificial atmosphere in their spacecrafts prior to Apollo 1. I do not understand how NASA planned to maintain this atmosphere, as even the human flatulence is composed of: Nitrogen: 20-90% Hydrogen: 0-50% (flammable) Carbon dioxide: 10-30% Oxygen: 0-10% Methane: 0-10% (flammable)
In a space settlement with an atmosphere consisting of only Oxygen and Nitrogen, how would the Methane be dealt with?