[chiralSPO]

Electric, or, as you point out, electricity can be used to generate hydrogen and oxygen, which, in turn, can be combusted in instances where a hot flame is required.

[alancalverd]

Using solar energy only, this machine recycles CO2 into a very versatile structural material and produces food and oxygen as byproducts. Rain-proof, self-replicating (just add bees) at no cost, and works for about 100 years with no maintenance.

[vdblnkr34 (OP)]

Practice showed that its not enough. Plus it was found that plants, trees can live in many different gases environment. So, it is under a question how did trees adopted to that. Also only at day light trees converting CO2 into O2, during the night it is opposite. O2 into CO2.

[Bored chemist]

Practice showed that its not enough. Plus it was found that plants, trees can live in many different gases environment. So, it is under a question how did trees adopted to that. Also only at day light trees converting CO2 into O2, during the night it is opposite. O2 into CO2.

Trees do not disappear at night.
The carbon they capture as cellulose etc is not suddenly reconverted to CO2 during darkness.

[alancalverd]

Trees do not disappear at night.

And there are trees in daylight somewhere, all the time. The CO2 moves around the earth to feed them, all by itself - no pumps required.

So, it is under a question how did trees adopted to that.

A very interesting question, but it belongs in a biology/evolution thread. Fact is that all modern plants absorb CO2 when the sun shines, and adapt themselves to grow more quickly when there is more CO2 in the atmosphere. Not sure what the upper limit is, but some local market gardeners run their greenhouses at 5% CO2 - toxic to humans - to get great yields of tomatoes and cucumbers.

[vdblnkr34 (OP)]

Why 5%? Did they try 100%?

[Kryptid]

Why 5%? Did they try 100%?

I imagine that would kill the plants. Plants need oxygen, too.

[alancalverd]

Not sure what the limit is for tomatoes, but at some point you need people to work in the greenhouse and you don't want to exhaust a dense gas that will kill the farm cats and dogs*, or waste a valuable asset. It's easy to reduce from 5% to <1% with a simple fan, and 5% would be tolerable for a short period in an emergency - say if you needed to rescue someone who inadvertently entered and lost consciousness. Neat line between hazardous and lethal.

* www.atlasobscura.com/places/cave-of-dogs

[Bored chemist]

5% would be tolerable for a short period in an emergency - say if you needed to rescue someone who inadvertently entered and lost consciousness.

Guess what usually happens in that circumstance.
https://www.thenews.com.pk/print/731374-six-booked-for-manslaughter-over-factory-workers-suffocation
https://www.livescience.com/57779-how-liquid-nitrogen-can-kill.html
https://tribune.com.pk/story/2228946/two-youngsters-die-trying-save-rooster-well

https://gulfnews.com/world/gulf/qatar/five-asian-workers-suffocate-to-death-in-sewage-network-manhole-1.233798

[vdblnkr34 (OP)]

I read news and they say its energy crisis in Europe. So, soon they have to make methane and propane from synthesis gas using CO2.

[Bored chemist]

synthesis gas

Where do we get that from?

[alancalverd]

Guess what usually happens in that circumstance.

"Inhaling liquid nitrogen" seems a pretty extreme activity. I've heard that cocaine eventually damages the nose, but where's the high that accompanies instant frostbite?
If someone had walked into a 5% CO2 enhanced  greenhouse and collapsed, I'd be reasonably happy to take a deep breath and drag him out without waiting for the exhaust fans to kick in. Less happy at 100% - a second breath would be ......breathtaking.

[alancalverd]

synthesis gas

Where do we get that from?

There are several experimental plants already synthesising fuels from atmospheric CO2 and electrolytic hydrogen, but I haven't seen a chemical factory as pretty as a forest or an orchard.

[vdblnkr34 (OP)]

They exist, one per country. Canada has one, USA has one, Russia has one. They was build in 194x.

[Bored chemist]

If someone had walked into a 5% CO2 enhanced  greenhouse and collapsed, I'd be reasonably happy to take a deep breath and drag him out without waiting for the exhaust fans to kick in.

If anyone had been able to ask the people who died in the incidents I listed, they would have said the same thing...

"Inhaling liquid nitrogen" seems a pretty extreme activity.

That's why nobody does it.
Why did you raise the idea?

[vdblnkr34 (OP)]

Synthesis gas is the base for all synthetic products on the market. Almost everything can be made from crude oil, can be made from synthesis gas. Its a mix of CO and H2. Usually used methane to do this conversion. Adding O2 to the CH4 give you a mix of CO+H2. Its a very big difficulty because you need to burn methane and stop this in time to have synthesis gas. For this is used high pressure, good heat and constant flow like a rocket engine or something.

[Bored chemist]

they have to make methane ... from synthesis gas using CO2.

synthesis gas

Where do we get that from?

Its a mix of CO and H2. Usually used methane to do this conversion.

So, you are saying that because they have no methane they will have to use synthesis gas made from methane.

Do you see a problem there?

[vdblnkr34 (OP)]

No. That how was found this synthesis gas long time ago. I offer to use CO2+H2O to convert it into CO+H2. Its going to be super easy.

We have lot of water and a lot of CO2.

[alancalverd]

Quote from: alancalverd on Today at 11:19:35

"Inhaling liquid nitrogen" seems a pretty extreme activity.

That's why nobody does it.
Why did you raise the idea?

You did!
https://www.livescience.com/57779-how-liquid-nitrogen-can-kill.html

But why is inhaling liquid nitrogen so deadly, given that nearly 80 percent of the air people breathe is made up of nitrogen?

[chiralSPO]

No. That how was found this synthesis gas long time ago. I offer to use CO2+H2O to convert it into CO+H2. Its going to be super easy.

We have lot of water and a lot of CO2.

I think you have your reaction wrong, the water gas shift (or reverse water gas shift) is:

H₂O + CO H₂ + CO₂

so if you want to consume water, then you need CO, and if you want consume CO₂, you need hydrogen.

It is technologically feasible to generate hydrogen from water in a sustainable way, and use that hydrogen to reduce carbon dioxide to synthesis gas, which can then be used to make a wide range of hydrocarbons. The problem is that it is not currently economically feasible. There are three ways to address that:
1) technological/scientific advances to increase the efficiency of the conversion (it will always require more energy than will be stored in the fuel produced, but sunlight is abundant and cheap, so that's ok)
2) Take advantage of economies of scale. There is no way that a "small" factory producing 1000 barrels of sustainable diesel could ever compete with the massive production and distribution infrastructure that the petrochemical industry has.
3) Actually make the producers of fossil fuels pay to manage their waste (we don't even need to tax CO₂, though that would be simple and fair). The companies that search for and extract fossil fuels are heavily subsidized, and have been able to get away with just dumping (or leaving) their waste to be a problem for whatever poor souls gave them extraction rights. And, somehow, whenever a company causes an environmental disaster that costs more than they are worth, the government steps in to clean up their mess, pat them on the head, and say, try better next time... smh