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Instant water cleaning method ‘millions of times’ better: study

cardiff.ac.uk

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Re: Instant water cleaning method ‘millions of times’ better: study

#121

Post by GrumpyNl »

55555 wrote: post #92
wolverine876 wrote: post #90

Earlier quoted context omitted.

Thanks for the insights, though let's remember that research is just a first step. This isn't a product being announced for the market. If we looked at the original research behind a lot of mature technology, we'd find the state of the technology to be similarly far from from production. Now others can try to reproduce it, refine it, find other methods of producing the same reactive oxygen species, find substitutes t…

> This isn't a product being announced for the market. The press release makes bold implications tbh

This works better for the funding round.

Re: Instant water cleaning method ‘millions of times’ better: study

#124

Post by jcranmer »

azalemeth wrote: post #106
jcranmer wrote: post #83

Oh dear. After reading the notes in the study itself about the scale this was done at, scaling up might be an issue: > A typical H₂O₂ synthesis reaction was carried out using 120 mg of 1% AuPd/TiO₂ [...] The reactor system was then pressurized, typically to 10 bar. The reactor was then cooled by a water bath to 2 °C. When the reactor had reached the required pressure and the flow through the system had stabilized, th…

What does MGD mean, and what is it in SI units? Million gallons per day? US gal or Imperial ones? (I'm not being facetious -- I genuinely don't know and it's my understanding that the US mix parts of the old British Imperial system, e.g. BTU, together with their own)

Yes, MGD means million gallons / day, and this is US gallons not Imperial (you should have been able to guess that from my reference to Virginia's standards--Virginia being a US state).

Re: Instant water cleaning method ‘millions of times’ better: study

#125

Post by engineer_22 »

slownews45 wrote: post #96
lugged wrote: post #61

Earlier quoted context omitted.

> The team showed that as the catalyst brought the hydrogen and oxygen together to form hydrogen peroxide, it simultaneously produced a number of highly reactive compounds, known as reactive oxygen species (ROS), which the team demonstrated were responsible for the antibacterial and antiviral effect, and not the hydrogen peroxide itself. > The catalyst-based method was shown to be 10,000,000 times more potent at kill…

They are testing against E Coli which is an easy target. My understand was always that E Coli is on the order of 1 minute. If you are into camping you might be thinking of things like Giardia - much harder to kill.

Cl cant kill Giardia oocysts, they have to be filtered out.

Re: Instant water cleaning method ‘millions of times’ better: study

#126

Post by gus_massa »

dmix wrote: post #109
gus_massa wrote: post #35

Earlier quoted context omitted.

Here the 10^8 improvement means that if the commercial method kills 99% of the bacteria, this method kills 99.99999999% of them.

People need to be taught basic statistics in school.

I don't think this is basic statistics. I think it the correct way of reporting the improvement, but it may be confusing for someone that does not understand the usual notation in the field. Moreover, I had to look at the paper to be sure what they were reporting. (Actually, they report the log of the improvement, i.e. something like "8" that is better to put in graph to compare different methods.)

Re: Instant water cleaning method ‘millions of times’ better: study

#127

Post by mannykannot »

azinman2 wrote: post #101
mannykannot wrote: post #89

Earlier quoted context omitted.

I do not understand why this could be regarded as a relevant response to the post you are replying to. You say "it’s unreasonable and incorrect to expect a full commercial solution to come directly out of a set of lab experiments", but the post you are replying to did little else but point out that this is essentially what the article is claiming. If you do not think the article was making such a claim, then that is…

That’s not what the article says. It says the new method “shows the POTENTIAL for revolutionising water disinfection technologies around the world” (emphasis mine). It’s talking about a method of creating disinfectants at the source rather than using chemicals. How to scale this up, deal with degrading catalysts, handle electrical demand, etc are all beyond the scope of an academic lab inventing a new method. They ju…

If you read the entire thread from the top, you will see that you are making a point that has already been acknowledged by everyone contributing to it. Bringing it up again merely loops the discussion back to a point where it has been before.

The fact that they are making bold claims about potential applications is sufficient to justify Kaibeezy's reply to riddly.

Re: Instant water cleaning method ‘millions of times’ better: study

#128

Post by gus_massa »

failwhaleshark wrote: post #103

Vaporware that can't make vapor. It's just invisiware. Edit / PSA: These type of sensationalized, "miracle" invention articles attract idiotic questions and uninteresting discussions. Please stop posting this kind of rubbish because it brings down the quality of the site.

I agree that it's very overhyped. If I had a magical button to change the upvotes, I'd put it in the 50-100 range. It's an interesting research result, but my guess is that it's much more difficult to apply in production than what the PR pretends. https://xkcd.com/1217/

But instead of complaining it's much better to upvote the technical comments that explain the problems. For example, the one about the flow rate that is very small. (I was not so worry about the cost of the catalyzers, but after seeing the flow rate, the cost of catalyzer/liter/year looks high.)

There are other about what an 10^8 improvement means, and I'd like to see one about how useful is 10^8 if any small hole downstream or bad handling will introduce many more bacteria. (It's like a sunscreen with a FPS of 10^8. It's nice, you can stay for eons under the sun, but forgetting it once per year will reduce the effective number to 10^4.)

Re: Instant water cleaning method ‘millions of times’ better: study

#129

Post by aardvarkr »

jcranmer wrote: post #83

Oh dear. After reading the notes in the study itself about the scale this was done at, scaling up might be an issue: > A typical H₂O₂ synthesis reaction was carried out using 120 mg of 1% AuPd/TiO₂ [...] The reactor system was then pressurized, typically to 10 bar. The reactor was then cooled by a water bath to 2 °C. When the reactor had reached the required pressure and the flow through the system had stabilized, th…

“When the reactor had reached the required pressure and the flow through the system had stabilized, the solvent (H²O, HPLC grade), typically at a flow of 0.2 ml min¯¹, was introduced into the system.“

You’re making such a big deal of the 0.2 ml/min that you didn’t stop to read that it’s talking about the amount of solvent… you’re just stirring up drama for the sake of drama

Re: Instant water cleaning method ‘millions of times’ better: study

#130

Post by azalemeth »

jcranmer wrote: post #124
azalemeth wrote: post #106

Earlier quoted context omitted.

What does MGD mean, and what is it in SI units? Million gallons per day? US gal or Imperial ones? (I'm not being facetious -- I genuinely don't know and it's my understanding that the US mix parts of the old British Imperial system, e.g. BTU, together with their own)

Yes, MGD means million gallons / day, and this is US gallons not Imperial (you should have been able to guess that from my reference to Virginia's standards--Virginia being a US state).

Thank you. (So about 0.0526 m^3/s.)
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