Author Topic: Water out of desert air  (Read 24515 times)

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Offline LabSpokane

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Re: Water out of desert air
« Reply #50 on: May 06, 2017, 08:46:10 am »

@LabSpokane Thunderf00t does not confuse boiling and vaporization, his math assumes a phase change only, no temperature change of the water.

Yes he does. He shows boiling water and states the energy needed to make it boil is the latent heat of vaporization. That is false. It is the energy required to turn all of the water from a 100C liquid to steam.

I have not watched the calculations portion. So that may be correct.
« Last Edit: May 06, 2017, 08:56:35 am by LabSpokane »
 

Offline TheAmmoniacal

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Re: Water out of desert air
« Reply #51 on: May 06, 2017, 08:59:19 am »
Another important detail they don't address is the cooling of the MOF, sure it will absorb water at ambient temperature and 20% RH as they say, and when placed in the sun at ~65 C some of that water will evaporate back off.

The water evaporated off the MOF can then re-condense on a passive heatsink placed above which remains at ambient temp - but the MOF won't absorb any more water without being cooled down again, i.e. placed out of the sun. And they plan on doing this passively? .. So humans have to do it?

@LabSpokane If you have water at the boiling point, the energy required to boil it all off is the latent heat of vaporization. The energy required to bring the water to the boiling point is m * C * (T_f - T_i), this amount is very small compared to the latent heat of vaporization, 334 kJ vs. 2.257 MJ for 1 kg of water. (m = mass, C = heat capacity)

If Thunderf00t said that the energy required to bring the water to a boil was the latent heat of vaporization, he was wrong.
 

Offline Hensingler

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Re: Water out of desert air
« Reply #52 on: May 06, 2017, 01:46:16 pm »
Didn't you read the paper? Are you accusing them of lying? Are you saying they falsified their data?

Of course they are lying and don't publish any data to justify the claims people are complaining about.

Quote
We report the design and demonstration of a device based on porous metal-organic framework-801 [Zr6O4(OH)4(fumarate)6] that captures water from the atmosphere at ambient conditions using low-grade heat from natural sunlight below one sun (1 kW per square meter). This device is capable of harvesting 2.8 liters of water per kilogram of MOF daily at relative humidity levels as low as 20%, and requires no additional input of energy.

There is no device and an extrapolation of their (non) proof of concept device and experiment could not produce the claimed performance.

At 20% by weight water absorption by the MOF it would have to pass through 14 collect/condense cycles during say 8 hours of sunlight. It is doubtful that a practical device could achieve a single cycle per day without additional solar panels to provide electricity for active cooling. Then there is the practical problem of passing around say 2000 m^3 of air over the MOF the kind of volume passed by a 30W fan running for 8 hours.

The claims from the paper quoted above are ridiculous and lies.

I look forward to your appeal to authority and face palm response which seems to be the only argument you have.


 

Offline LabSpokane

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Re: Water out of desert air
« Reply #53 on: May 06, 2017, 02:07:00 pm »
@LabSpokane If you have water at the boiling point, the energy required to boil it all off is the latent heat of vaporization. The energy required to bring the water to the boiling point is m * C * (T_f - T_i), this amount is very small compared to the latent heat of vaporization, 334 kJ vs. 2.257 MJ for 1 kg of water. (m = mass, C = heat capacity)

If Thunderf00t said that the energy required to bring the water to a boil was the latent heat of vaporization, he was wrong.

I am well aware of these facts, but thank you.
 

Offline mtdoc

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Re: Water out of desert air
« Reply #54 on: May 06, 2017, 02:29:17 pm »
How real science is done (e.g. this paper):

1) Have a novel idea/hypothesis  (MOF-801 has properties that make it superior to current absorbents).

2) Develop a theory for why your hypothesis might be correct (or incorrect). (Done)

3) Make predictions based on your theoretical model. (Done)

4) Devise and perform an experiment(s) and collect data. (Done)

5). Document and analyze your data. (Done).

6) If necessary revise your hypothesis and go back to step 2.

7) Submit your findings for peer review and (if worthy) publication. (Done).

8.) Await further review by colleagues and other scientists.(In process)

9.) If necessary, and based on further data (yours or as published by others), review and revise, go back to step 2.

--------------

How anti-science and/or pseudoscience is practiced on the interwebs (unfortunately including by some on this forum):

1) Make a claim or refute published research or scientific consensus (in this case published research)

2) Back up your claims with:

A) Verbal statements such as:
"I know this is wrong (or right)"
"They're lying"
"It smells like BS "
"I can't imagine this is true (or not true)"
" Dr X says it's true (or not true)"
"It's only a theory"
 Or other such statements which are basically the equivalent of " The bible says so"

B) Cursory calculations or repetition of elementary scientific principles which may or may not have some bearing on your idea or the published science being refuted.

3) If speaking to a general audience use lots of impressive sounding technical jargon that may or may not be accurate, relevant or fairly represent what is being refuted.

4) Accuse the published science of being politically motivated without offering any proof of this.

5) Misrepresent the published science either intentionally or unintentionally based on inaccurate media reports.

6) Use examples of prior research that was later proved wrong while ignoring the fact that the proving wrong is part of the scientific process and was accomplished using real science.

7) Never collect any of your own data and publish it in a reputable peer reviewed journal.

8.) Make highly stylized sensationalistic youtube videos employing the methods above.

9) Accuse those who point these things out of "Appealing to the authority of science".



 

Offline mtdoc

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Re: Water out of desert air
« Reply #55 on: May 06, 2017, 03:20:03 pm »
I trust Newton's Law of Cooling far more than arguments from authority.
Nothing in this paper violates that law. It's not argument from authority. It's published experimental data. It is science!

Quote
The need to assist in "visualizing" condensation is a blatant falsehood. The evidence of condensation is liquid water, which is visible to the naked eye. Liquid water would have been equally visible on the surface of their magical heat sink which dissipates power without raising its temperature.

Keeping the condenser temp above the dew point is a red herring. Had they used a heat sink only, that criterion would have easily been met as the temperature of the heat sink would have rapidly approached equilibrium with the vapor temperature. Oh, but then a lot less water would condense, wouldn't it?  I'm sure you must understand the importance of that.

Once again, I believe you are failing to understand the difference between basic science and engineering.

Visualizing and documenting droplet formation and growth as a function of MOF temperature was part of validating their theory. You can't adequately visualize this - even with the naked eye - if the glass is obscured by condensation and you certainly can't document it for publication without clear photographs. If they said "droplet formation and growth occurred in xx manner with increasing temperature over xx time period - we observed this through glass partially obscured by condensation and were unable to provide any clear photographic documentation of this" their paper would rightly be rejected by the reviewers!

If they were trying to deceive someone, why disclose the active controlling of the condenser temperature?  They were trying to fully characterize the adsorption-desorption properties of MOF-801, nothing more. They were not attempting to build a working prototype.

Science is very different than engineering in this regard. You can't just build a "black box" and measure data in and out then derive a transfer function and be done.  The point of science is trying to understand the underlying process. Sometimes that involves direct visualization. It often involves controlling variables artificially in order to gather data.

A very obvious next step for this would be to build a prototype device with no TE cooled condenser and only passive cooling with adequate heatsinking and measure, refine, measure, etc to try and optimize water production. 

Maybe it would work, maybe not. The theory and experimental data presented in this paper suggests that it should and it is worth building. That in a nutshell is what the authors are saying.

If a working prototype was built, THAT would be an engineering paper. As such it would not likely be published in Science.

I think the authors of this study made a big mistake by using the term "Proof of concept device" when really it is just an experimental apparatus.  In this case proof of concept != prototype.

Unfortunately - even though it was a small part of their paper - use of that term seems to have triggered engineers and others so inclined to focus on this part of the paper and to think it is an engineering study, therefore looking at it from that perspective (understandable since that is what engineers are familiar with).  But even worse, it led to erroneous reporting by the media.
 

Offline TheAmmoniacal

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Re: Water out of desert air
« Reply #56 on: May 06, 2017, 03:39:17 pm »
This idea is not novel or original at all, the last few years of MOF research have all discussed the possible use as atmospheric water generators, first relevant hits on google scholar cited below.
Quote
Furukawa, Hiroyasu, et al. "Water adsorption in porous metal–organic frameworks and related materials." Journal of the American Chemical Society 136.11 (2014): 4369-4381.
Canivet, Jérôme, et al. "Water adsorption in MOFs: fundamentals and applications." Chemical Society Reviews 43.16 (2014): 5594-5617.
Burtch, Nicholas C., Himanshu Jasuja, and Krista S. Walton. "Water stability and adsorption in metal–organic frameworks." Chemical reviews 114.20 (2014): 10575-10612.
Biswal, Bishnu P., et al. "Pore surface engineering in porous, chemically stable covalent organic frameworks for water adsorption." Journal of Materials Chemistry A 3.47 (2015): 23664-23669.
Hao, Guang?Ping, et al. "Unusual Ultra?Hydrophilic, Porous Carbon Cuboids for Atmospheric?Water Capture." Angewandte Chemie International Edition 54.6 (2015): 1941-1945.
de Lange, Martijn F., et al. "Adsorption-Driven Heat Pumps: The Potential of Metal–Organic Frameworks." Chemical reviews 115.22 (2015): 12205-12250.

Just look at the relevant discussion from the first paper:

Quote
Applications to Thermal Battery and Water Delivery in Remote Desert Regions
With these values, we can estimate how much heat can be stored in 15 kg of MOF-801-P. Assuming that the storage capacity and Qst of MOF-801-P are 20 wt % (at P/P0 = 0.1) and 60 kJ mol–1, respectively, the total heat expected to be released is 10 MJ. If such a system is operated for 1 h with 65% efficiency, the power capability is equivalent to 1.8 kW: a value approaching the 2.5 kW power target for typical thermal batteries as set by DOE.(31)

The temperature effect on water uptake is also important to realize another application of water adsorption in MOFs: temperature-triggered water capture and release systems, where atmospheric water would be captured and delivered at different temperatures in areas with high temperature contrasts between day and night. For example, in the city of Tabuk in Saudi Arabia, the typical summer temperature and relative humidity during day time are respectively 40 °C and 5%, drastically changing at night to 25 °C and 35%. Assuming P/P0 × 100 = RH%, the working capacity of MOF-841 between P/P0 = 0.05–0.35 is more than 40 wt % (Figure S58 in SI), which is the largest obtained among all Zr-MOFs. If 15 kg of MOF-841 is deployed in Tabuk under these optimal conditions, it should be able to deliver 6.3 L of pure water per day.



The reason why all of them haven't been in the news like these MIT graduates is because they did the science properly.
 

Offline mtdoc

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Re: Water out of desert air
« Reply #57 on: May 06, 2017, 05:46:22 pm »
This idea is not novel or original at all, the last few years of MOF research have all discussed the possible use as atmospheric water generators, first relevant hits on google scholar cited below.

Original science does not require a complete lack of previous research in that area. In fact quite the opposite - almost all science builds on previous published research. The journal Science does not publish research that does not report something new or previously unpublished. Period. Full Stop.

Quote
Just look at the relevant discussion from the first paper:

And your point is?  That other research has been done in this area - in this case using a different MOF?

Quote
The reason why all of them haven't been in the news like these MIT graduates is because they did the science properly.

So your argument is that all science that gets picked up and reported in the mainstream press (usually inaccurately) is not proper science? ::) 
(And what makes you think the MIT and UC Berkeley researchers publishing this are all MIT graduates?)

How exactly are researchers supposed to prevent their published research from being reported in the media?

The way to refute published science is by either publishing your own data or if you find some fundamental flaw in a publication, by sending a letter to the journal editor or other reputable publication in the field.

Science is cutthroat competitive so if any such flaw is present (certainly possible), it will be forthcoming in reputable publications.  AKA the scientific process

Innuendo,  irrelevant or illogical postings on an internet forum and youtube videos just don't cut it I'm afraid.
« Last Edit: May 06, 2017, 05:48:12 pm by mtdoc »
 

Offline GeorgeOfTheJungle

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Re: Water out of desert air
« Reply #58 on: May 06, 2017, 05:57:44 pm »
If Thunderf00t said that the energy required to bring the water to a boil was the latent heat of vaporization, he was wrong.

He does not say it, but words the sentences in such a way that most people will (erroneously) believe that to be the case. He also played some dubious tricks in a previous vidjeo about CO2 / global warming / atomic bombs and the energy the earth receives from the sun.
« Last Edit: May 10, 2017, 12:04:51 pm by GeorgeOfTheJungle »
The further a society drifts from truth, the more it will hate those who speak it.
 

Offline josecamoessilva

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Re: Water out of desert air
« Reply #59 on: May 06, 2017, 06:18:24 pm »

Quote
Just look at the relevant discussion from the first paper:

And your point is?  That other research has been done in this area - in this case using a different MOF?

Would that be the same first paper that was co-autored by the inventor of Metal-Organic Frameworks (yes, the whole field), Omar Yaghi, who's a coauthor of the Science paper?

"Water Adsorption in Porous Metal–Organic Frameworks and Related Materials" Hiroyasu Furukawa†, Felipe Gándara†, Yue-Biao Zhang†, Juncong Jiang†, Wendy L. Queen§, Matthew R. Hudson?, and Omar M. Yaghi*†

 (As usual in these things, the laboratory directors are the last on the author list, in the case of the Science paper, Yaghi (Berkeley) and Wang (MIT). It's one of those things people who read scientific papers tend to know. Hint: "et al." short for "et alli" means "and others.")

Obvious troll is obvious.

Here's the process of science at work:

http://science.sciencemag.org/content/early/2017/05/03/science.aan5763

Quote
After an investigation, the Central Ethical Review Board in Sweden has recommended the retraction of the Report “Environmentally relevant concentrations of microplastic particles influence larval fish ecology,” by Oona M. Lönnstedt and Peter Eklöv, published in Science on 3 June 2016 (1).

Making youtube videos instead of submitting one's analysis to peer review: not how a real scientist addresses a problem with the science in a peer-reviewed paper. Ironically, that's how Thunderf00t attacks creationists and climate change deniers, that they make videos criticizing evolution and climate science that has been peer-reviewed but never submit their "analysis" to peer review themselves...

 A bit sad to see that Dave retweeted the vid.

(I had forgotten how strongly some people are triggered by the three letters "MIT," for reasons that are all too obvious. Also always wondered why Caltech gets a pass.)

Edited to add: Interesting conversation at U of the Berks with Omar Yaghi with some interesting points about science and society:

« Last Edit: May 06, 2017, 06:36:51 pm by josecamoessilva »
 

Offline TheAmmoniacal

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Re: Water out of desert air
« Reply #60 on: May 06, 2017, 06:41:48 pm »
You guys makes me sad.
 

Offline mtdoc

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Re: Water out of desert air
« Reply #61 on: May 06, 2017, 06:56:21 pm »

 A bit sad to see that Dave retweeted the vid.


I feel the same.  I think that Dave has been a big TF fan.  But I also know that Dave is very pro science and pro science education.  After watching his discussion with Shahriar I'm hoping that he is coming to better appreciate the difference between real science, pseudoscience and anti-science.  Niel DeGrasse Tyson is also good in that way.    I'm also hoping that he sticks to debunking the crowd funded type pseudoscience scams in the careful, non hyped way he did in his initial debunk videos and does not follow the TF path of ill-informed anti-science videos. 
« Last Edit: May 06, 2017, 07:00:07 pm by mtdoc »
 

Offline Hensingler

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Re: Water out of desert air
« Reply #62 on: May 06, 2017, 07:22:20 pm »
How exactly are researchers supposed to prevent their published research from being reported in the media?

Maybe they could not include greenwash bullshit lies in their papers clearly intended to get technically illiterate journalists and eco warriors gagging for it.

Just a thought....

If this paper had been honest it would not have been reported.
« Last Edit: May 06, 2017, 07:26:17 pm by Hensingler »
 

Offline TheAmmoniacal

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Re: Water out of desert air
« Reply #63 on: May 06, 2017, 07:26:19 pm »
How exactly are researchers supposed to prevent their published research from being reported in the media?

Maybe they could not include greenwash bullshit lies in their papers clearly intended to get technically illiterate journalists and eco warriors gagging for it.

Just a thought....

And have one of the largest press offices of any university write and circulate press releases that does nothing but hype, where do you think all the journalists get their story? http://news.mit.edu/2017/MOF-device-harvests-fresh-water-from-air-0414

Do you see all the "Press mentions" on the right side? What does it remind you of? Every kickstarter scam I can think of.. "Featured in.."
« Last Edit: May 06, 2017, 07:29:28 pm by TheAmmoniacal »
 

Offline LabSpokane

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Re: Water out of desert air
« Reply #64 on: May 06, 2017, 07:33:08 pm »
I trust Newton's Law of Cooling far more than arguments from authority.
Nothing in this paper violates that law. It's not argument from authority. It's published experimental data. It is science!

From the paper:
Quote
During water harvesting (left), the desorbed vapor is condensed at the ambient temperature and delivered via a passive heat sink, requiring no additional energy input.

Quote
For visualization purposes, we used a condenser with a temperature controller to maintain the temperature slightly below ambient, but above the dew point, to prevent vapor condensation on the inner walls of the enclosure. However, active cooling is not needed in a practical device since the hot desorbed vapor can condense at the cooler ambient temperature using a passive heat sink.

If water would condense on the walls at ambient temperature, it would whether the TE cooler was there or not. 

The authors clearly state that the thermoelectric cooler can be equivalently replaced by a heat sink.  Newton's Law of Cooling states this is impossible. A heat sink must become warmer than ambient in order to dissipate power. The water volumes condensed in the paper depend upon a surface that *does not increase in temperature*. You continue to argue from authority on this matter, rather than accept the simple fact that heat cannot be transferred from one body to another without a temperature differential.  This reality negates virtually the entire premise of the paper: that it is possible for this hypothetical passive device to condense large amounts of water from the air without becoming warmer or without an input of work. 

And the next step is not to use a heat sink to demonstrate this.  That was the *first* step.  The experimental data, as I've already told you, conveniently omits the energy input required to condense water vapor, despite how ridiculously easy this would be to measure and record.  Even easier would have been to not use the thermoelectric cooler at all and simply rely upon its very ample heat sink as shown in the photo.

« Last Edit: May 06, 2017, 07:34:41 pm by LabSpokane »
 

Offline mtdoc

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Re: Water out of desert air
« Reply #65 on: May 06, 2017, 07:35:29 pm »
From first hand experience I will tell you that with rare exception, university scientists have little or no control over what their institution's public relations office publicizes. Anyone who suggests otherwise is just making sh*t up.

Edited to add: Interesting conversation at U of the Berks with Omar Yaghi with some interesting points about science and society:


Watching this now. Excellent video. Thanks for posting it.
 

Offline mtdoc

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Re: Water out of desert air
« Reply #66 on: May 06, 2017, 07:49:18 pm »
rather than accept the simple fact that heat cannot be transferred from one body to another without a temperature differential.

Doh ! Really ::).  No one here nor the authors of this paper would refute that fact. If you cannot read the paper and understand why that is not what is being asserted here then I can't help you.

Quote
And the next step is not to use a heat sink to demonstrate this.  That was the *first* step.

You continue to refuse to acknowledge or are unable to  understand that this is not an engineering paper. The intent is not to build or demonstrate a working prototype. The intent is to characterize the adsorption/desorption properites of MOF-801.

The rest of your post is full of similarly unsupported or irrelevant assertions equivalent to a "the bible says so" argument.
 

Offline Hensingler

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Re: Water out of desert air
« Reply #67 on: May 06, 2017, 08:46:30 pm »
You continue to refuse to acknowledge or are unable to  understand that this is not an engineering paper. The intent is not to build or demonstrate a working prototype. The intent is to characterize the adsorption/desorption properites of MOF-801.

Quoting the paper again
Quote
Finally, a proof-of-concept MOF-801 water-harvesting prototype was built to demonstrate the viability of this ap-proach outdoors (Fig. 4A). ....

It seems you are the one refusing to acknowledge or understand what was written in the paper.
 

Offline TheAmmoniacal

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Re: Water out of desert air
« Reply #68 on: May 06, 2017, 08:48:26 pm »
Important to keep in mind that the optimistic claims in the paper are based on a computer simulation they did, but they are not clear about this.
 

Offline mtdoc

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Re: Water out of desert air
« Reply #69 on: May 06, 2017, 09:19:12 pm »
Quoting the paper again
Quote
Finally, a proof-of-concept MOF-801 water-harvesting prototype was built to demonstrate the viability of this ap-proach outdoors (Fig. 4A). ....

Yes and it did exactly that by demonstrating and allowing them to characterize the adsorption/desorption properties of MOF-801 over a few hours outdoors.

As I stated earlier, I think the use of the term "proof of concept" was unwise since it seems to have induced a Pavlovian type neurologic tic in some engineers causing them to perseverate on this small portion of the paper thinking it is about engineering a prototype.
 

Offline mtdoc

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Re: Water out of desert air
« Reply #70 on: May 06, 2017, 09:31:57 pm »
Important to keep in mind that the optimistic claims in the paper are based on a computer simulation they did, but they are not clear about this.
Not exactly true.
 

Offline josecamoessilva

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Re: Water out of desert air
« Reply #71 on: May 06, 2017, 09:48:30 pm »
At about half the length of TF's video, here's Yaghi talking about the MOFs in general. Because it's educational and not a "look how stupid those people at MIT and Science Magazine are" video, it won't appeal to TF's troll entourage.



Note: how often Yaghi mentions collaboration with other scientists, how he attributes major improvements in the technology to his students, the long-ish history of MOFs and their applications, the fact that Yaghi keeps mentioning open problems, the long list of publications in the slide footers, and the large scale use of MOFs being developed by BASF.

And as to the other lab director involved in the Science paper, Evelyn Wang of MIT, she seems to know a bit more about using solar power than people who yell "thermodynamics," Tourrete's-like, at any thing that TF tweets:



Interesting idea, making solar power dispatchable right at the generation point (rather than using grid-scale batteries); that would be a game changer for solar.
 

Offline TheAmmoniacal

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Re: Water out of desert air
« Reply #72 on: May 06, 2017, 09:48:47 pm »
Quoting the paper again
Quote
Finally, a proof-of-concept MOF-801 water-harvesting prototype was built to demonstrate the viability of this ap-proach outdoors (Fig. 4A). ....

Yes and it did exactly that by demonstrating and allowing them to characterize the adsorption/desorption properties of MOF-801 over a few hours outdoors.

As I stated earlier, I think the use of the term "proof of concept" was unwise since it seems to have induced a Pavlovian type neurologic tic in some engineers causing them to perseverate on this small portion of the paper thinking it is about engineering a prototype.

All the thermodynamics and water-absorbing properties of MOF-801 have been characterized in previous studies, as I linked earlier. It's just that in those (proper) studies they say MOF-801-P and MOF-801-SC for crystalline powder and single crystal forms, something they do not specify in the Science paper (although they do refer to it as powder).

@mtdoc This is where they get the "2.8 liters per kilogram of MOF" figures from:


Quote
Simulated adsorption-desorption dynamics for the MOF-801 layer with the optimized packing porosity of 0.7 are shown in Fig. 3 for 1 sun and realistic boundary conditions for heat loss (a natural heat transfer coefficient of 10 W m–2 K–1 and standard ambient temperature). In this simulation, MOF-801 was initially equilibrated at 20% RH, and the vapor content in the air-vapor mixture that surrounds the layer during desorption increased rapidly from 20 to 100% RH at 25°C. This scenario is more realistic compared with the model experiment described above because water is harvested by a condenser at ambient temperature. Once solar irradiation was stopped, the air-vapor concentration reverted to 20% RH for vapor adsorption from ambient air, and the heat from the adsorption process was transferred to the surroundings. A detailed description of the boundary conditions and idealizations in the simulation is given in section S8 of the supplementary materials. First, water uptake decreased with time during solar heating and water condensation, then increased through adsorption, as shown by the simulated water uptake profiles for the MOF-801 layer at thicknesses of 1, 3, and 5 mm (Fig. 3). The temperature correspondingly increased and then decreased with time. Continuously harvesting water in a cyclic manner for a 24-hour period with low-grade heat at 1 kW m–2 can yield ~2.8 liters kg–1 day–1 or ~0.9 liters m–2 day–1 with a 1-mm-thick layer. Alternatively, per one cycle, a 5-mm-thick layer of MOF-801 can harvest ~0.4 liters m–2. Our findings indicate that MOFs with enhanced sorption capacity and high intracrystalline diffusivity—along with an optimized crystal diameter, crystal density, and thickness of the MOF layer—can further boost the daily quantity of water harvested from an arid environment.

The paper describes three different things, 1. preliminary prototype, 2. Simulation and optimization using COMSOL Multiphysics, 3. proof-of-concept prototype (performed over two days on the roof of MIT and then extrapolated).

Good night, nice fighting with you all.   :box:
« Last Edit: May 06, 2017, 09:52:11 pm by TheAmmoniacal »
 

Offline mtdoc

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Re: Water out of desert air
« Reply #73 on: May 06, 2017, 10:35:51 pm »

All the thermodynamics and water-absorbing properties of MOF-801 have been characterized in previous studies, as I linked earlier. It's just that in those (proper) studies they say MOF-801-P and MOF-801-SC for crystalline powder and single crystal forms, something they do not specify in the Science paper (although they do refer to it as powder).

That is a misrepresentation or perhaps you don't understand the scientific process?  In fact if you read the first paragraph, they specifically reference the study you sited earlier (Furukawa et al 2014 - ref 10 in their paper) and go on to detail their further elaboration on the earlier work. That is how science works. One study builds on another.

Quote
The paper describes three different things, 1. preliminary prototype, 2. Simulation and optimization using COMSOL Multiphysics, 3. proof-of-concept prototype (performed over two days on the roof of MIT and then extrapolated).

Another misrepresentation. There is no preliminary prototype only the one POC device.  And you left out their experiments and data performed in an environmental chamber - probably the most important part of the paper (much more than the POC device). Did you leave that out intentionally?

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Good night, nice fighting with you all.   :box:
It's an enjoyable debate minus the "pathetic" ad hominens  ;)
 


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