Science
Related: About this forumYet another perpetual motion machine in the scientific literature involving hydrogen.
The paper to which I'll refer in this post is this one: Boosting the Hydrogen Production Coupling with Electrochemical Methanol Oxidation to Formate Using Monolayered Layered Double Hydroxide Nanosheets Jing Ren, Lisha Xing, Tianyi Lai, and Yufei Zhao Industrial & Engineering Chemistry Research 2023 62 (43), 17553-17561.
Once again, the magic word "hydrogen," subject to continuous abuse to encourage the continuous use and expanded use of dangerous fossil fuels via exergy destruction, appears in the scientific literature as the subject of a perpetual motion machine.
I discussed another hydrogen perpetual motion machine recently in this space: Wunderbar! A Hydrogen Based Perpetual Motion Machine.
Let's start here: Electricity is generally not "green." It is the most thermodynamically degraded form of energy in common use.
I have covered the exergy destruction associated with hydrogen in some detail here: A Giant Climate Lie: When they're selling hydrogen, what they're really selling is fossil fuels.
Included in that post is this graphic:
The caption:
Progress on Catalyst Development for the Steam Reforming of Biomass and Waste Plastics Pyrolysis Volatiles: A Review Laura Santamaria, Gartzen Lopez, Enara Fernandez, Maria Cortazar, Aitor Arregi, Martin Olazar, and Javier Bilbao, Energy & Fuels 2021 35 (21), 17051-17084]
I referred to this graphic, and reproduced it previously, discussing a paper in the journal I discussed above here: The current sources and uses of hydrogen.
There you have it: 10% of the hydrogen produced on this planet, almost all of it produced by the use of dangerous fossil fuels (including that produced by electrolysis as a side product of chlorine manufacture, since electricity is mostly produced from dangerous fossil fuels), is used to make methanol. I assume, based on general knowledge, that methanol so made because the general method for making methanol, partial oxidation of dangerous natural gas, produces some formic acid and formaldehyde as a side product, and this is recovered by hydrogenation to methanol. All of these industrial reactions are probably carried out in a Haber Bosch type plant where hydrogen is made by reforming dangerous natural gas.
All of these reactions, including partial oxidation of dangerous natural gas destroy exergy.
So what do these authors propose to improve the disastrous exergy destruction associated with water hydrolysis?
Let's start with the delusional marketing found in the introduction of the paper, about something that doesn't actually exist on any scale that matters, "green hydrogen," a line of bullshit wishful thinking that is drilled into public consciousness by dishonest advertising, including some found here at DU by posters I regard as dangerous fossil fuel marketeers.
The MOR, methanol oxidation reaction, described above, delineates the nature of this approach as a perpetual motion machine. Other species mentioned are also made from hydrogen, notably, N2H4 and urea.
Climate change is getting worse faster.
Captive hydrogen can be made from thermochemical cycles which can only be carried out continuously and thus cleanly using nuclear heat. It is, in my view, the only way that the external costs of hydrogen manufacture can be rendered clean and sustainable, and in fact, offers a potential, via process intensification, to increase the thermodynamic efficiency of nuclear energy to unprecedented levels.
In 2011, the late great Nobel Laureate George Olah proposed a closed carbon cycle to address the on going and accelerating tragedy of climate change: Anthropogenic Chemical Carbon Cycle for a Sustainable Future George A. Olah, G. K. Surya Prakash, and Alain Goeppert Journal of the American Chemical Society 2011 133 (33), 12881-12898.
His proposal involved the hydrogenation of CO2 to methanol and/or dimethyl ether (DME), the latter being a nontoxic wonder fuel capable of replacing petroleum, in particular diesel fuel, gasoline, LPG, dangerous natural gas, coal and even fluorinated refrigerants.
If the methanol is made by partial oxidation of dangerous natural gas (as most of it is), by the way, this paper does not imply a perpetual machine, but rather is an approach to making the already unacceptably dirty use of hydrogen by electrolysis an even dirtier enterprise.
Have a pleasant Sunday. Enjoy the upcoming holiday.
BigOleDummy
(2,274 posts)the ins and outs of molecular chemistry or anything else in your field. I want to thank you for the "dumbed down" versions you provide. I don't mean that in a bad way. But reading your posts always leaves me feeling that "hey, maybe I understand this a little better". I understand physics enough to be extremely wary of any claims of "free energy", but your explanations provide me with at least a glimmer of understanding. Sometimes a glimmer is all you can hope for and in MY case thats true about too many subjects. Hey, I came by my username honestly!
NNadir
(34,645 posts)I have, in fact, spent much of my adult life seeking to be the dumbest person in the room.
It's a great way to learn.
masmdu
(2,574 posts)NNadir
(34,645 posts)Electricity is still thermodynamically degraded, irrespective of source. If Japan's electricity was 100% powered by nuclear energy it might be worthy of consideration, but it isn't.
Electrolysis further degrades the thermodynamics of electricity to store it as hydrogen, destroying more exergy.
It would be wiser to use any electricity devoted to electrolysis to the grid.
In a thermochemical cycle, the best of which, in my view, is one of the earliest considered, the sulfur iodine cycle, (SI cycle) because it is amenable to continuous flow chemistry, heat energy currently released into the environment (nuclear energy's most problematic external cost) would be recovered by exergy, and the cooling steps involved in cooling the SO2/O2 hot gas stream to prevent reoxidation might be utilized to generate electricity as a side product. If the side product electricity is available to a 100% nuclear grid, electrolysis might be marginally acceptable.
This approach is called "process intensification." Process intensification is the best industrial scale approach to sustainability there is in my view.
I believe China is testing a nuclear powered SI cycle, but I don't have an update on the status.
Thanks for your question.