> we absorb CO2 and water vapor from the air into an aqueous electrolyte....to get the fuel out of the water...we have a carbon nanotube membrane Considering t

> we absorb CO2 and water vapor from the air into an aqueous electrolyte....to get the fuel out of the water...we have a carbon nanotube membrane Considering the partial pressure of CO2 in the atmosphere is miniscule, the eventual concentration of the product will also be very low. And because the water molecule is the smallest, you will not be extracting fuel from the solution, but rather extracting water until the fuel concentration is sufficient. Together, this implies that the energy expended in separation must be high, and therefore the process must be inefficient. Is this correct, or have I made a bad assumption somewhere?