Why can't we break down the CO2 coming out of a car's exhaust into relatively harmless C and O2?

Sort of like a second catalitic converter. Asked by Rock 44 months ago Similar questions: break CO2 coming car's exhaust harmless O2 Transportation > Automotive - Makes and Models.

Similar questions: break CO2 coming car's exhaust harmless O2.

Transportation > Automotive - Makes and Models.

Because it takes more energy to do this than was generated burning the gasoline in the first place. What is needed is to use a fuel that has harmless exhaust, like a hydrogen fueled car. The real issue is generating the hydrogen in the first place.

Keep in mind, coal is pretty close to pure carbon, and the laws of thermodynamics say that you can't convert from coal to energy+CO2 and other byproducts and back again to essentially coal without loss of efficiency.

Because it would take a lot of energy to break down CO2 to C and O2. In particular, whatever energy your car got out of burning the gasoline - including the energy wasted as heat and friction - would be approximate amount of energy needed to break the CO2 apart. I say "approximate" because gasoline is a compound of hydrogen (H) and carbon (C).

So the energy from burning the H could still be used by your car, but all of the enrgy from burning the C would be required to break the CO2 apart again.

We could actually do this. But the bad news is ..... It would be super expensive and very energy intensive, because of the thermodynamics of the system. The CO2 molecule has chemical bonds in it (two C=O double bonds) that take a LOT of energy to break.

Moreover, when you calculate the balance between the energy in the products (graphite, oxygen gas) and the starting material (CO2), that balance hugely favors the starting material. So the amount of energy it would take to drive this chemical reaction is very large. Where would all that energy come from?

It would probably generate yet MORE carbon dioxide, either directly or indirectly. So the answer is: sure, we could devise chemical reactions to break down CO2. Even better, we could devise chemistry that would sequester the CO2, rendering it harmless from the greenhouse gas perspective.

But the cost would be great and probably counterproductive if your goal is to reduce greenhouse gas. On a side note, I would mention that growing green plants already do this. They convert the CO2 in the air into C, which goes into the plant, and O2, released into the air, by photosynthesis.

The energy for this process comes from sunlight. So, if you want to ameliorate the CO2 from your car's tailpipe, plant some trees. (Of course, when the trees eventually die and burn/decay, that dratted carbon will be released BACK into the atmosphere ... but now we are really getting off topic :) .

Becuz Because we got energy by burning the C and O2 into CO2. To reverse the process would require the input of just as much energy. No free lunch..

You could but a CO2 scrubber on vehicles, like they have on chimneys, but the cost would be prohibitive for the device as well as it's maintanence.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.