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Gallium helps convert CO2 into Carbon and Oxygen

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Re: Gallium helps convert CO2 into Carbon and Oxygen

#61

Post by mcdonje »

dr_dshiv wrote: post #21
cletus wrote: post #11

So let's do some math. Let's consider natural gas. According to the US government [1], natural gas produced 1.358x10^12 kWh of power and 5.6x10^8 metric tons of CO2 so 1 metric ton of CO2 equates to ~2400 kWh of produced power. This post suggests the energy cost is ~230kWh/ton. This is an important sanity check because it means that (capital costs aside) and if it scales you could technically remain carbon neutral fo…

>I'll repeat here--that I don't believe altruism will solve greenhouse gas emissions and global warming: it'll only be solved when it becomes economic to do so. Completely agree. We need governments to ensure externalities (both positive and negative) are reflected in market pricing so that economic forces can operate efficiently. Implication: there must be a debt to pay for past and present GHG output. It should not…

So, a robust carbon tax.

Re: Gallium helps convert CO2 into Carbon and Oxygen

#62

Post by c1sc0 »

hcurtiss wrote: post #56
dr_dshiv wrote: post #21

Earlier quoted context omitted.

>I'll repeat here--that I don't believe altruism will solve greenhouse gas emissions and global warming: it'll only be solved when it becomes economic to do so. Completely agree. We need governments to ensure externalities (both positive and negative) are reflected in market pricing so that economic forces can operate efficiently. Implication: there must be a debt to pay for past and present GHG output. It should not…

Who would pay that debt for past emissions, and what price should they pay?

Boomers. Everything they own.

Re: Gallium helps convert CO2 into Carbon and Oxygen

#63

Post by rtpg »

hcurtiss wrote: post #56
dr_dshiv wrote: post #21

Earlier quoted context omitted.

>I'll repeat here--that I don't believe altruism will solve greenhouse gas emissions and global warming: it'll only be solved when it becomes economic to do so. Completely agree. We need governments to ensure externalities (both positive and negative) are reflected in market pricing so that economic forces can operate efficiently. Implication: there must be a debt to pay for past and present GHG output. It should not…

Who would pay that debt for past emissions, and what price should they pay?

Perhaps society as a whole should just try to solve these problems.

This is the tarpit of market-based solutions: debating endlessly about who bears costs, instead of just doing collective things collectively. And if you do have markets, every middleman and their dog will demand their slice of the pie.

Re: Gallium helps convert CO2 into Carbon and Oxygen

#64

Post by nkingsy »

credit_guy wrote: post #50
cletus wrote: post #11

So let's do some math. Let's consider natural gas. According to the US government [1], natural gas produced 1.358x10^12 kWh of power and 5.6x10^8 metric tons of CO2 so 1 metric ton of CO2 equates to ~2400 kWh of produced power. This post suggests the energy cost is ~230kWh/ton. This is an important sanity check because it means that (capital costs aside) and if it scales you could technically remain carbon neutral fo…

> This is an important sanity check You have a bug somewhere, I'm not sure where. Roughly speaking the heat of combustion is proportional to the number of atoms of oxygen in the molecules coming out of the reaction. So CH4 + 2 O2 = CO2 + 2 H20 If you hypothetically split CH4 first, you get CH4 + 2 O2 = (C + 2 H2) + 2 O2 = (C + O2) + (2 H2 + O2) = CO2 + 2H20 The first reaction is endothermic, but it absorbs much less…

The article clearly states a claimed 92% efficiency.

Re: Gallium helps convert CO2 into Carbon and Oxygen

#65

Post by voakbasda »

rtpg wrote: post #63
hcurtiss wrote: post #56

Earlier quoted context omitted.

Who would pay that debt for past emissions, and what price should they pay?

Perhaps society as a whole should just try to solve these problems. This is the tarpit of market-based solutions: debating endlessly about who bears costs, instead of just doing collective things collectively. And if you do have markets, every middleman and their dog will demand their slice of the pie.

The only way to get everyone to participate in a solution will be regulation. The last thing that I want is the government regulating this market. We will end up with another cartel like the oil industry.

Re: Gallium helps convert CO2 into Carbon and Oxygen

#67

Post by theropost »

cletus wrote: post #11

So let's do some math. Let's consider natural gas. According to the US government [1], natural gas produced 1.358x10^12 kWh of power and 5.6x10^8 metric tons of CO2 so 1 metric ton of CO2 equates to ~2400 kWh of produced power. This post suggests the energy cost is ~230kWh/ton. This is an important sanity check because it means that (capital costs aside) and if it scales you could technically remain carbon neutral fo…

Also keep in mind the limited supply/uses of Gallium at the moment, it tends to be a biproduct from other mining activities. If suddenly there were a large and scaled demand for this material, then I am quite sure we would see a huge spike in price in the near/medium term, and future price would depend on the new demand, and capabilities to get sufficient supply. $250/kg is pretty cheap at the moment;

Re: Gallium helps convert CO2 into Carbon and Oxygen

#68

Post by kortex »

adrian_b wrote: post #19
cletus wrote: post #11

So let's do some math. Let's consider natural gas. According to the US government [1], natural gas produced 1.358x10^12 kWh of power and 5.6x10^8 metric tons of CO2 so 1 metric ton of CO2 equates to ~2400 kWh of produced power. This post suggests the energy cost is ~230kWh/ton. This is an important sanity check because it means that (capital costs aside) and if it scales you could technically remain carbon neutral fo…

"how the CO2 needs to be delivered": The experiments described in the paper have used pure CO2. The conversion process is unlikely to work directly with air, because it decomposes CO2 into solid carbon partially oxidated and dioxygen. If one of the products of the catalyzed reaction, i.e. oxygen from the air, would be present in a much larger concentration than the input substance (CO2), like in the air, the conversi…

It's possible this might work with de-oxygenated air. As long as the nitrogen does not react with the generated oxygen and release NOx, this could be done with an adsorption process, which is a lot cheaper and less energy than full air separation.

Even then, NOx can be mitigated. This process is fascinating in that unlike most "breakthroughs" this has a semblance of a chance of scaling.

Re: Gallium helps convert CO2 into Carbon and Oxygen

#69

Post by photochemsyn »

adrian_b wrote: post #19
cletus wrote: post #11

So let's do some math. Let's consider natural gas. According to the US government [1], natural gas produced 1.358x10^12 kWh of power and 5.6x10^8 metric tons of CO2 so 1 metric ton of CO2 equates to ~2400 kWh of produced power. This post suggests the energy cost is ~230kWh/ton. This is an important sanity check because it means that (capital costs aside) and if it scales you could technically remain carbon neutral fo…

"how the CO2 needs to be delivered": The experiments described in the paper have used pure CO2. The conversion process is unlikely to work directly with air, because it decomposes CO2 into solid carbon partially oxidated and dioxygen. If one of the products of the catalyzed reaction, i.e. oxygen from the air, would be present in a much larger concentration than the input substance (CO2), like in the air, the conversi…

Preconcentration of CO2 from air makes a lot of sense as you can then do various types of industrial chemistry on a pure CO2 stream at greater efficiency. From here you can go towards either methane and long-chain fuel hydrocarbons (Sabatier, modified Fischer-Tropsch, etc) or, as in this paper, towards solid carbon forms.

Making something like graphite from pure CO2 has certain advantages as well (easier to get purity) and graphite electrodes are used in scrap steel recycling and other industries.

For comparison, see the ISS use of Sabatier reaction and some issues they had with catalyst poisoning:

https://ntrs.nasa.gov/search.jsp?R=20140002591

This indicates that power plant emissions, typically contaminated with sulfur / arsenic / mercury / nitrogen etc. , at about 10% CO2 as I recall, would be a very poor option relative to direct air capture.

As far as scaling, even existing systems (see ISS) could be scaled fairly rapidly and would be able to produce enough fuel for specialized uses, i.e. plausibly supplying SpaceX / ULA/ etc. rocket launches as a first step, then moving to supply airports with jet fuel for long-distance travel at a much larger scale.

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