I'm designing a world with advanced life forms that use a sulphur-based biochemistry (see this link for context). I would like to create a carbon cycle analogous to Earth, where:
- Photosynthesis transforms carbon dioxide (CO2) and water (H2O) into glucose (C6H12O6) and oxygen (O2).
- Cellular respiration consumes O2 and releases CO2 + H2O, maintaining equilibrium.
In my world, I would like:
- Photosynthesis to take methane (CH4) and sulphuric acid (H2SO4) to produce sulphur dioxide (SO2) and a hydrocarbon that performs the same role as glucose (let's call it substance X).
- Cellular respiration to consume SO2 and release CH4 + H2SO4, again maintaining equilibrium.
- Substance X would therefore need to have a molecular formula with 1×C, 6×H, 2×O (or a multiple in proportion, e.g., 2×C, 12×H, 4×O).
- No oxygen (O2) in the atmosphere.
- No production of water in the photosynthetic reaction.
The ideal solution would be a hydrocarbon that actually exists, with a molecular formula using the atoms mentioned above. If that's not possible, what if:
- Sulphur trioxide (SO3) is used instead of SO2?
- A third, nitrogen-based gas is added (such as ammonia or nitric acid) such that photosynthesis takes CH4, H2SO4, third gas; and respiration takes SO2 to release CH4, H2SO4 and the third gas.