Talk:Carbon dioxide

unclear properties values in brackets

Some values have (15) or (30) added - that needs explaining or correction eg. Vapor pressure 5.7292(30) MPa, 56.54(30) or Critical point (T, P) 304.128(15) K (30.978(15) °C), 7.3773(30) MPa (72.808(30) atm) 2A01:C22:CD7C:E00:7983:CA1C:9736:D1BC (talk) 08:44, 24 August 2023 (UTC)

It’s not unclear. This is a widely used notation to indicate how much uncertainty is expected in a measured quantity. See the Wikipedia article on uncertainty for more information. Qflib, aka KeeYou Flib (talk) 14:28, 24 August 2023 (UTC)

Hm, I guess the repeating numbers 15 and 30 does bear closer examination. Maybe they are old citations? Qflib, aka KeeYou Flib (talk) 15:37, 24 August 2023 (UTC)

First it would be easier to understand if ± was used however if these were uncertainties then

5.7292(30) MPa, 56.54(30) atm would translate to 5.7292 ± 0.0030 for MPa and 56.54 ± 0.30 atm but those are the same measurement just with different units. So the uncertainty can't be the same as 5.7262 MPa (-0.003) are 56.5132 atm and not 56.24 - so i conclude these are not uncertainties. (other 7.3743MPa is 72.77868 atm would work (72.778atm) as here the atm value is given with 3 decimals but even if we use 56.54(3)atm it seem to work but 56.542(30) would be 56.512 not 56.5132 as the certainty wouldn't have ⅒ but ¹/₉.₈₆₉₂₃₃ as a factor - So it is very unlikely that the MPa and atm values were from two different measurements with different uncertainties that accidentally have the same numerical value - while just a typo moved a decimal place. 2A01:C22:CD04:2B00:98A2:90A1:EB26:C385 (talk) 09:04, 25 August 2023 (UTC)

I completely agree. I think that we should therefore remove the numbers within the parentheses, and then try to find better sources. Qflib, aka KeeYou Flib (talk) 22:01, 25 August 2023 (UTC)

Ambiguous units of measurement like "ppm" and "%" across this article

There are many data with ambiguous units of measurement like "ppm" and "%" across this article (and many other articles across Wikipedia), without a clear explanation what those units stand for. Without a clear explanation, those units can stand for mass per volume, volume per volume, mole per mole or who knows what else. Can someone clarify what those units stand for, despite that is not clarified in the sources? The data about the concentrations of carbon dioxide (and other suffocating and toxic gases and substances) in the air, water, food, drinks, products, etcetera, is a very important information for readers, especially non-expert ones, so, editors should be notified about the very existence of the ambiguous "ppm", "%" and similar ambiguous units across Wikipedia. Let's discuss. I am opening a debate. What do you think? Do you agree or disagree with me, and explain why. Thanks in advance for your opinion. Bernardirfan (talk) 18:08, 30 August 2023 (UTC)

WP:JUSTFIXIT with a WP:SCIRS source. Zefr (talk) 19:06, 30 August 2023 (UTC)

I think another editor has now fixed the problem. Thanks for pointing it out. Not everything needs a debate, as Zefr rightly points out. Qflib, aka KeeYou Flib (talk) 14:09, 6 September 2023 (UTC)

Thank you Qlib and Zefr for resolving my {{clarify}} tags. Bernardirfan (talk) 09:41, 16 October 2023 (UTC)

Semi-protected edit request on 31 August 2023

2.49.118.238 (talk) 14:49, 31 August 2023 (UTC)

But if he das he Eed yt account then I don’t see why not just follow the link to the tweet he is posting and

 Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. — Paper9oll (🔔 • 📝) 14:55, 31 August 2023 (UTC)

Medical uses

I removed the following content that is unsourced. All biomedical claims need WP:MEDRS sourcing because we don't want people to harm themselves. Clayoquot (talk | contribs) 00:46, 30 October 2024 (UTC)

Medical and pharmacological uses

In medicine, up to 5% carbon dioxide (130 times atmospheric concentration) is added to oxygen for stimulation of breathing after apnea and to stabilize the O₂/CO₂ balance in blood.

Carbon dioxide can be mixed with up to 50% oxygen, forming an inhalable gas; this is known as Carbogen and has a variety of medical and research uses.

Another medical use are the mofette, dry spas that use carbon dioxide from post-volcanic discharge for therapeutic purposes.

Due weight issues regarding commercial use

Uses of CO2 in 2015

The article currently gives a lot of weight to the use of CO2 in the food and beverage industries and various industrial niches. These are relatively small uses of CO2, which is primarily used in urea production and in the oil and gas industry or not used at all. I plan to update it to give a more balanced overview of commercial use. To replace the last paragraph of the lead, I have drafted the following text (adapted largely from the IEA, CC-BY):

Globally, 230 million tonnes (Mt) of carbon dioxide (CO2) are used every year. The largest consumer is the fertilizer industry, where 130 Mt CO2 is used in urea manufacturing. The oil and gas industry consumes 70 to 80 Mt CO2 annually for enhanced oil recovery. Other commercial applications include food and beverage production, metal fabrication, cooling, fire suppression and stimulating plant growth in greenhouses. Some usage of CO2 results in long-term sequestration underground or in products. However, as the the potential for commercial use of CO2 is relatively small, the vast majority of CO2 is a waste product.

Clayoquot (talk | contribs) 21:38, 30 October 2024 (UTC)

Content cut from article

I've removed the content below from the "Commercial uses" section as they describe technologies that are still at pre-commercial stages of development (or possibly at extremely early commercial deployment if I've missed a recent update). The older predictions of glory have not gone anywhere. Recent sourcing on these issues: Allam cycle [1][2], enhanced coal bed methane recovery[3], algal biofuels.[4] Clayoquot (talk | contribs) 18:54, 1 November 2024 (UTC)

Supercritical CO₂ is used as the working fluid in the Allam power cycle engine.

In enhanced coal bed methane recovery, carbon dioxide would be pumped into the coal seam to displace methane, as opposed to current methods which primarily rely on the removal of water (to reduce pressure) to make the coal seam release its trapped methane.

Bio transformation into fuel

Main article: Carbon capture and utilization

It has been proposed that CO₂ from power generation be bubbled into ponds to stimulate growth of algae that could then be converted into biodiesel fuel. A strain of the cyanobacterium Synechococcus elongatus has been genetically engineered to produce the fuels isobutyraldehyde and isobutanol from CO₂ using photosynthesis.

Researchers have developed an electrocatalytic technique using enzymes isolated from bacteria to power the chemical reactions which convert CO₂ into fuels.