2CO < > CO2 + C

this was the equation i stumbled across a while ago involving carbon monoxide and carbon dioxide

when the mix is hot, the equation is shifted to the left to more carbon monoxide

when the mix is colder it shifts to the right to more carbon dioxide

the cross over point is 700 degrees as i understand it

if you just had hot carbon monoxide would the equation still hold true, that is as the mix was cooled below 700 degrees would carbon be produced as a natural process as well as carbon dioxide?

or

does this equation imply that to work you need carbon present in the first place to balance?

its an idea thats been bouncing around for a while until i saw the equation again

the idea i had at the time to remove carbon dioxide from the atmosphere invloved this

first you pump air into water where the carbon dioxide disolves as carbonic acid into a solution of calcium hydroxide and precipitates into calcium carbonate

the calcium carbonate is removed quickly before the solution becomes acidic and dissolves the calcium carbonate

the calcium carbonate is then heated and the carbon dioxide is evolved from the calcium carbonate , the calcium carbonate is reused the carbon dioxide is then heated beyond 700 degrees and (hopefully) it transforms into carbon monoxide and then cooled to make carbon dioxide and carbon.

to me it looks as if the carbon is an integral part of the equation , that is the carbon needs to part of the equation first , you couldn’t just heat carbon dioxide and then cool it to make carbon dust and carbon dioxide

what say ye?

hang on

i’ve asked this before on the sssf i think

i’ll search there

nope

no one could actually answer it there either

and that was in 2009

i might put it up on a chemistry Q and A site

what say ye?
———————
What are you going to do with the CO2?

All sorts of problems with your thinking there wookie. I barely know where to start.

Stealth said:

what say ye?
———————
What are you going to do with the CO2?

well if i heat it i turn into CO

what i’m thinking that if you then cool it then the hot CO turns into cool carbon dioxide and carbon

i’m not sure if that happens though. you’d need soot in the first place to balance the equation?

if you didn’t it would mean that as the CO cooled it would produce soot and carbon dioxide.??

morrie said:

All sorts of problems with your thinking there wookie. I barely know where to start.

forget the personal attack

if you can’t answer the question then let someone else who can

nothing personal

cooling carbon monoxide does not produce carbon and carbon dioxide.

wookiemeister said:

morrie said:

All sorts of problems with your thinking there wookie. I barely know where to start.

forget the personal attack

if you can’t answer the question then let someone else who can

nothing personal

I am a qualified Chemical Engineer. What you are suggesting is nonsense.

i’ll do some more research on it anyway

morrie said:

cooling carbon monoxide does not produce carbon and carbon dioxide.

why

wookiemeister said:

morrie said:

cooling carbon monoxide does not produce carbon and carbon dioxide.

why

There is no driving force.

morrie said:

wookiemeister said:

morrie said:

cooling carbon monoxide does not produce carbon and carbon dioxide.

why

There is no driving force.

you mean heat?

You have neglected stoichimetry. In other words mass balance.

wookiemeister said:

morrie said:

wookiemeister said:

why

There is no driving force.

you mean heat?

Gibbs Freen Energy change

morrie said:

wookiemeister said:

morrie said:

There is no driving force.

you mean heat?

Gibbs Freen Energy change

Free

morrie said:

You have neglected stoichimetry. In other words mass balance.

if you started with a hot volume of carbon monoxide then

2CO wouldn’t go to CO2 and C

balances to me

2 C and 2 O goes to CO2 and C

two lots of C and 2 lots of O each side.

at anyrate i didn’t claim to be an expert

it was a question after all

wookiemeister said:

morrie said:

You have neglected stoichimetry. In other words mass balance.

if you started with a hot volume of carbon monoxide then

2CO wouldn’t go to CO2 and C

balances to me

2 C and 2 O goes to CO2 and C

two lots of C and 2 lots of O each side.

Where did you get your carbon monoxide from?

morrie said:

wookiemeister said:

morrie said:

You have neglected stoichimetry. In other words mass balance.

if you started with a hot volume of carbon monoxide then

2CO wouldn’t go to CO2 and C

balances to me

2 C and 2 O goes to CO2 and C

two lots of C and 2 lots of O each side.

Where did you get your carbon monoxide from?

In the other reaction that you mention, using calcium hydroxide, you need to take into account that calcium hydroxide requires calcium carbonate as a starting material, plus lots of coal, gas or other fuel to drive out the carbon dioxide to form calcium hydroxide.

I really wasn’t trying to make this a personal attack. I was just saying as someone with knowledge in the area, there are a lot of flaws in your concept.

morrie said:

morrie said:

wookiemeister said:

if you started with a hot volume of carbon monoxide then

2CO wouldn’t go to CO2 and C

balances to me

2 C and 2 O goes to CO2 and C

two lots of C and 2 lots of O each side.

Where did you get your carbon monoxide from?

In the other reaction that you mention, using calcium hydroxide, you need to take into account that calcium hydroxide requires calcium carbonate as a starting material, plus lots of coal, gas or other fuel to drive out the carbon dioxide to form calcium hydroxide.

i was rather hoping that you could use solar energy to do this

the calcium carbonate is simply a reuseable material that is simply heated by the sun in a solar furnace and CO2 is driven off

what i’m proposing that you use the suns energy to drive the reaction to drive off the CO2 from CaCO3 and heat the carbon dioxide.

the equation says that carbon is needed in the first place not just CO2 thats where the CO comes from

wookiemeister said:

morrie said:

morrie said:

Where did you get your carbon monoxide from?

In the other reaction that you mention, using calcium hydroxide, you need to take into account that calcium hydroxide requires calcium carbonate as a starting material, plus lots of coal, gas or other fuel to drive out the carbon dioxide to form calcium hydroxide.

i was rather hoping that you could use solar energy to do this

the calcium carbonate is simply a reuseable material that is simply heated by the sun in a solar furnace and CO2 is driven off

Very inefficient. There are other carbon dioxide capture systems that use less energy. Ethanolamines for example.

morrie said:

wookiemeister said:

morrie said:

In the other reaction that you mention, using calcium hydroxide, you need to take into account that calcium hydroxide requires calcium carbonate as a starting material, plus lots of coal, gas or other fuel to drive out the carbon dioxide to form calcium hydroxide.

i was rather hoping that you could use solar energy to do this

the calcium carbonate is simply a reuseable material that is simply heated by the sun in a solar furnace and CO2 is driven off

Very inefficient. There are other carbon dioxide capture systems that use less energy. Ethanolamines for example.

i was aiming for simplicity rather than efficiency, the energy used in the system would come from the sun so efficiciency wouldn’t be an issue.

the idea was to make it easy to make by anyone.

the flaw with it is how to make CO from CO2 without adding C into the mix

wookiemeister said:

morrie said:

wookiemeister said:

i was rather hoping that you could use solar energy to do this

the calcium carbonate is simply a reuseable material that is simply heated by the sun in a solar furnace and CO2 is driven off

Very inefficient. There are other carbon dioxide capture systems that use less energy. Ethanolamines for example.

i was aiming for simplicity rather than efficiency, the energy used in the system would come from the sun so efficiciency wouldn’t be an issue.

the idea was to make it easy to make by anyone.

the flaw with it is how to make CO from CO2 without adding C into the mix

CO2 > CO + 1/2 O2

morrie said:

wookiemeister said:

morrie said:

Very inefficient. There are other carbon dioxide capture systems that use less energy. Ethanolamines for example.

i was aiming for simplicity rather than efficiency, the energy used in the system would come from the sun so efficiciency wouldn’t be an issue.

the idea was to make it easy to make by anyone.

the flaw with it is how to make CO from CO2 without adding C into the mix

CO2 > CO + 1/2 O2

While that is an explosive mixture, you could separate the two gases and use the carbon monoxide as a fuel.

morrie said:

wookiemeister said:

morrie said:

Very inefficient. There are other carbon dioxide capture systems that use less energy. Ethanolamines for example.

i was aiming for simplicity rather than efficiency, the energy used in the system would come from the sun so efficiciency wouldn’t be an issue.

the idea was to make it easy to make by anyone.

the flaw with it is how to make CO from CO2 without adding C into the mix

CO2 > CO + 1/2 O2

was just thinking about that in the shower

would you heat up the CO2 to loosen the O from the CO2 molecule pressure??

now assuming you could separate one oxygen atom from the CO2 molecule would the reversible reaction as it stands be valid

that is carbon monoxide standing alone cooled from its hot state go to Co2 and C?

still no?

the equation is still balanced all you’ve done is start from the CO side

anyway gone for 20 hours now

i’ll keep track of thread on road

wookiemeister said:

now assuming you could separate one oxygen atom from the CO2 molecule would the reversible reaction as it stands be valid

that is carbon monoxide standing alone cooled from its hot state go to Co2 and C?

still no?

the equation is still balanced all you’ve done is start from the CO side

Nope. Just cos it is balanced does not mean it will proceed.

morrie said:

wookiemeister said:

now assuming you could separate one oxygen atom from the CO2 molecule would the reversible reaction as it stands be valid

that is carbon monoxide standing alone cooled from its hot state go to Co2 and C?

still no?

the equation is still balanced all you’ve done is start from the CO side

Nope. Just cos it is balanced does not mean it will proceed.

For example, cooling carbon dioxide will not split it into carbon and oxygen, though the equation would be balanced.

well the wiki article about the reaction seems to say otherwise

hot carbon dioxide when it cools does turn into carbon dioxide and carbon

While formation enthalpy of CO2 is higher than that of CO, the formation entropy is much lower. Consequently, according to the Ellingham diagram, the overall free energy change of formation of CO2 by oxidation of carbon is almost constant and indifferent of the temperature, while the free energy change of formation of CO is a decreasing line. These two lines meet at 700℃, so the Boudouard reaction implies that on lower temperatures the equilibrium is on the exothermic carbon dioxide side and on higher temperatures the endothermic formation of carbon monoxide is the dominant reaction.

For instance, in the high temperature reducing environment of a smokestack, carbon monoxide is the stable product. When the carbon monoxide reaches the top of the smokestack, and the cooler air…………….

the Boudouard Reaction takes place; the carbon monoxide is oxidized into carbon dioxide, and the graphite precipitates (reduces) as soot. The Ellingham diagram is a plot of the Gibbs free energy change for a reaction (ΔG), versus temperature.

as far as i can see this is exactly what will happen

Although the damaging effect of carbon monoxide on catalysts is undesirable, this reaction had been utilized in producing graphite flakes

wiki

it would seem that carbon is indeed formed

wookiemeister said:

well the wiki article about the reaction seems to say otherwise

hot carbon dioxide when it cools does turn into carbon dioxide and carbon

While formation enthalpy of CO2 is higher than that of CO, the formation entropy is much lower. Consequently, according to the Ellingham diagram, the overall free energy change of formation of CO2 by oxidation of carbon is almost constant and indifferent of the temperature, while the free energy change of formation of CO is a decreasing line. These two lines meet at 700℃, so the Boudouard reaction implies that on lower temperatures the equilibrium is on the exothermic carbon dioxide side and on higher temperatures the endothermic formation of carbon monoxide is the dominant reaction.

For instance, in the high temperature reducing environment of a smokestack, carbon monoxide is the stable product. When the carbon monoxide reaches the top of the smokestack, and the cooler air…………….

the Boudouard Reaction takes place; the carbon monoxide is oxidized into carbon dioxide, and the graphite precipitates (reduces) as soot. The Ellingham diagram is a plot of the Gibbs free energy change for a reaction (ΔG), versus temperature.

as far as i can see this is exactly what will happen

Seems like I might have to eat my words there on the Gibbs Free Energy change. However, the next problem is that the kinetics of the reaction are really slow and the cooler you get the slower it will go.

morrie said:

wookiemeister said:

well the wiki article about the reaction seems to say otherwise

hot carbon dioxide when it cools does turn into carbon dioxide and carbon

While formation enthalpy of CO2 is higher than that of CO, the formation entropy is much lower. Consequently, according to the Ellingham diagram, the overall free energy change of formation of CO2 by oxidation of carbon is almost constant and indifferent of the temperature, while the free energy change of formation of CO is a decreasing line. These two lines meet at 700℃, so the Boudouard reaction implies that on lower temperatures the equilibrium is on the exothermic carbon dioxide side and on higher temperatures the endothermic formation of carbon monoxide is the dominant reaction.

For instance, in the high temperature reducing environment of a smokestack, carbon monoxide is the stable product. When the carbon monoxide reaches the top of the smokestack, and the cooler air…………….

the Boudouard Reaction takes place; the carbon monoxide is oxidized into carbon dioxide, and the graphite precipitates (reduces) as soot. The Ellingham diagram is a plot of the Gibbs free energy change for a reaction (ΔG), versus temperature.

as far as i can see this is exactly what will happen

Seems like I might have to eat my words there on the Gibbs Free Energy change. However, the next problem is that the kinetics of the reaction are really slow and the cooler you get the slower it will go.

wookiemeister springs, his fangs glistening in the damp night air as his victim stumbles

its suggested that the reaction swings almost entirely to the CO2 and soot side

but

it does say that the cross over point is 700 deg

but

it does say that the cross over point is 700 deg

Gas-phase production of carbon single-walled nanotubes from carbon
monoxide via the HiPco process: A parametric study

DOI: 10.1116/1.1380721

hey by the way morrie

the carbon dioxide to carbon monoxide and oxygen reaction

is that carried out under low/high pressure and with heat??

Glance Fleeting said:

Gas-phase production of carbon single-walled nanotubes from carbon
monoxide via the HiPco process: A parametric study

DOI: 10.1116/1.1380721

from what i’ve read the catalyst isn’t quite a catalyst

the CNT whilst being a seeding surface gets bonded to the carbon so as far as i read it

“The iron catalyst particles are bound to the CNT and hence do not constitute a separate exposure hazard.”

what i’m thinking is that instead of having a separate catalyst you could simply inject the carbon residue from earlier reactions to create the seed to make carbon, thsi could be blown around inside a chamber as the carbon monoxide is injected.