Environment & Energy

NNadir

(34,654 posts) Thu Oct 24, 2024, 08:53 PM Oct 24

A Survey of the Number of Papers Published and Patents Filed on "Sustainable" CO2 Conversion Processes.

The paper to which I will briefly refer is this one, published earlier this year: Perspectives on Advancing Sustainable CO2 Conversion Processes: Trinomial Technology, Environment, and Economy Lourdes F. Vega, Daniel Bahamon, and Ismail I. I. Alkhatib ACS Sustainable Chemistry & Engineering 2024 12 (14), 5357-5382.

To be clear, with some very major caveats, I consider "CCU," Carbon Capture and Utilization, to be potentially a worthy enterprise, but only in the case where the carbon dioxide is removed either directly from the air or (better) via a pathway through seawater, and then only when fossil fuels are banned. This requirement involves a very heavy energy penalty, inasmuch as the laws of thermodynamics dictate that not only must all of the energy that put the CO₂ in the first place must be reproduced, but even more energy is required to overcome the entropy of mixing. It is an energetic loser. It is therefore neither simple nor "green" without clean carbon free energy, and no, the tiresome reactionary fantasies about so called "renewable energy" will not cut it despite the text I'll quote below.

Still, CO₂ conversion is a "thing," and a lot has been written about it.

That's what's interesting about the paper, is a measure of how much has been written about the topic. So let me jump right to figure 1 in the paper and its caption:

The caption:

Figure 1. (a) Number of publications and (b) number of patents in CO2 conversion to different products in the period 2003–2023 according to Scopus. Green colors stand for CO₂ to C1 conversions, blue colors stand for CO₂ to C2+, and gray stands for mineralization. (c) Perspective of (potential) market distribution of products from CO2 utilization, year 2030. The numbers indicate the Mt/year of utilized CO₂. Storage (dark gray), fuel (green), mineralization (light gray), biochar (yellow), EOR (pink), and chemicals (dark green). (7,9)

One may wonder what the mechanism of "sustainable CO₂ conversion" might be. Um...um...um...the usual suspects, I guess.

The Paris Agreement (1) marks a milestone in the need for commitments of actions to mitigate climate change, (2,3) one of the consequences being the launch of net-zero strategies by several countries. With 36.8 Gt of CO2 emitted in 2022, (4) radical actions are needed to change the current trajectory of emissions, including game-changing moves in technology development and deployment. The International Renewable Energy Agency (IRENA) in their 2022 report (5) World Energy Transitions Outlook listed six technological avenues for reducing greenhouse gas (GHG) emissions by 2050, highlighting that 90% of decarbonization will involve renewable energy through direct supply of low-cost power, efficiency, electrification, carbon capture and storage (CCS), and green hydrogen (H2, produced from the electrolysis of water using renewable energy). Green H2 and CCS are expected to contribute approximately 30% of the total reductions. (5) Driving green H2 and CCS toward larger contributions for CO2 emission reductions requires advancements in making available (and emerging) technologies cheaper and more efficient, hand in hand with policies geared toward closing the cost gaps, and increasing economic benefits, while ensuring the clear environmental benefits versus the technologies they are replacing.

There's that magical "green hydrogen" again. Unfortunately as I often repeat "green hydrogen" is a Potemkin product dishonestly pushed by fossil fuel companies to rebrand their products as "green." Hydrogen is overwhelmingly made using the steam reforming of dangerous fossil fuels.

I showed a table of how much "green hydrogen" is made in China, which is often marketed by fossil fuel interests as a hydrogen nirvana in spite of the fact that in China, hydrogen is a coal nirvana, or perhaps a coal hell.

Plans for "Green" Hydrogen Transition in China: An Amusing Paper Involving Doubly Wasteful Energy Storage.

Tables S9, S10, and S11 offer soothsaying about various "scenarios" - "scenario" being the IEA terms for soothsaying based on a number of "if" statements, usually involving super optimistic statements about so called "renewable energy" despite the fact that the already trillion dollar expenditures on this lipstick on the fossil fuel pig has done effectively nothing to address extreme global heating, since under the expenditures the rate of extreme global heating is accelerating, not decelerating despite these expenditures.

Only the values from the entry for 2020 are likely to be based on actual data beyond soothsaying. For convenience, I'll produce them here from table S9:

BG refers to biogas reforming, CG, to coal reforming, SMR, steam methane reforming, natural gas reforming, and EXT refers to industrial byproducts, presumably oil refining. Based on the data for 2020, which is probably the most accurate, in "percent talk" that advocates of so called "renewable energy" like to use to obscure its uselessness, 98.88% of the hydrogen used to power those Chinese devices in the ads posted here was generated by the use of dangerous fossil fuels, accompanied by exergy destruction. Solar energy produced 0.3%, hydro, 0.8%.

If we converted all the bullshit about the existence of "green hydrogen" into hydrogen, it might be clean, but as of now, hydrogen is a dirty fuel.

I am a fan of the wonder fuel DME, dimethyl ether, mentioned in the papers graphic, which can be made in two steps - with some evidence that a "one pot" approach will work under ideal conditions - by hydrogenating CO₂, sustainably if, and only if, the hydrogen is made from the thermochemical splitting of H₂O using nuclear power sources of heat as primary energy.

This would extend the benefits of nuclear energy - under process intensification procedures - to portable use, and eliminate the need for all fluid fossil fuels.

Regrettably, as things stand now, CO₂ conversion, is not a workable solution, because the use of dangerous fossil fuels is increasing, not decreasing.

The 2024 IEA World Energy Outlook has been released; World Energy Demand Grew by 13 Exajoules, Solar and Wind by 2 EJ.

World Energy Outlook 2024

Table A.1a: World energy supply Page 296.

Have a nice day tomorrow.

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