Instant water cleaning method ‘millions of times’ better: study • Hacker News Board

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

#101

Post by azinman2 » Wed, Jul 07, 2021, 5:12 AM UTC

mannykannot wrote: post #89

azinman2 wrote: post #64

Earlier quoted context omitted.

I think the point is the science can be useful in that endeavor by demonstrating a new approach one can take. That’s not to say it’s all that would be required. It’s unreasonable and incorrect to expect a full commercial solution to come directly out of a set of lab experiments.

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 just demonstrated the potential.

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

#102

Post by honie » Wed, Jul 07, 2021, 6:02 AM UTC

mmazing wrote: post #98

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…

If its effectiveness is as good as they say, seems like you could just use 1,000,000x less catalyst and end up with something as effective as current technology. $190 million -> 190 bucks ;) Seriously though, couldn't they just use far less catalyst and not have to deal with the prices you've calculated?

> Seriously though, couldn't they just use far less catalyst and not have to deal with the prices you've calculated?

The flow rate is likely positively correlated with catalyst loading (in the part that we care about) and the calculation is already based on the flow rate of 0.2 ml min¯¹ they reported in the paper. The reported flow rate is also likely already optimised for the Nature Communications paper.

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

#103

Post by failwhaleshark » Wed, Jul 07, 2021, 6:15 AM UTC

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.

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

#104

Post by yxhuvud » Wed, Jul 07, 2021, 6:15 AM UTC

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…

I wonder if it could replace clorinated water in swimming pools though.

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

#105

Post by rdiddly » Wed, Jul 07, 2021, 6:20 AM UTC

Kaibeezy wrote: post #59

rdiddly wrote: post #53

Earlier quoted context omitted.

Remember science is still just science; it's not necessarily for commercializing.

The researcher himself is directly quoted saying things like “revolutionising water disinfection technologies around the world”. If that’s not backed up by it being feasible or valuable commercially, then the criticism is spot on.

Yeah the researcher is already pretty far into the commercial realm with that kind of statement. I'm just saying, the point of science is to find out stuff or increase certainty about stuff. So even an experiment that finds another way to disinfect water that doesn't work, has scientific value because now we know that doesn't work.

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

#106

Post by azalemeth » Wed, Jul 07, 2021, 6:28 AM UTC

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)

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

#107

Post by dmix » Wed, Jul 07, 2021, 6:43 AM UTC

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

Mostly context on why researching such a thing would be valuable.

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

#108

Post by neltnerb » Wed, Jul 07, 2021, 6:46 AM UTC

honie wrote: post #102

mmazing wrote: post #98

Earlier quoted context omitted.

If its effectiveness is as good as they say, seems like you could just use 1,000,000x less catalyst and end up with something as effective as current technology. $190 million -> 190 bucks ;) Seriously though, couldn't they just use far less catalyst and not have to deal with the prices you've calculated?

> Seriously though, couldn't they just use far less catalyst and not have to deal with the prices you've calculated? The flow rate is likely positively correlated with catalyst loading (in the part that we care about) and the calculation is already based on the flow rate of 0.2 ml min¯¹ they reported in the paper. The reported flow rate is also likely already optimised for the Nature Communications paper.

It is very unlikely that they could have even explored the full parameter space if they wanted to, it's such a huge undertaking. It's probably optimized under some constraints, but there's a huge number of things involved -- support material, surface area, catalyst metal, alloying, promoters, pretreatment, temperature, pressure, flow rate -- my experience has been that you can take any catalyst and make it work a lot better by just picking an understudied parameter and optimizing it.

My guess is that you could drop the catalyst noble metal content by 10-100x or even substitute an alternative catalyst and find a combination of conditions and catalyst that works. It's not a sure thing, but it's not unlikely. Sometimes it's as simple as swapping one support for another and the performance goes up 100x, it's just a lot of tests to run that don't even apply to both lab and commercial scales anyway (so a lot of the tests are never practical to run anyway).

I think it'd be a bigger deal if it didn't require pressurization to 10 bar personally, pumps are expensive to operate and catalysts are a one-time-cost (if you're lucky).

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

#109

Post by dmix » Wed, Jul 07, 2021, 6:47 AM UTC

gus_massa wrote: post #35

rmah wrote: post #20

Yeah, the use of "millions of times better" just doesn't pass the sniff test. Given that current commercial methods kill 90%+ bacteria in water, thus, nothing can be even 2x better...and makes me suspicious of any claim in the article. Hopefully it can help people in areas that are currently without clean water, but I'm not holding my breath.

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.

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

#110

Post by mprovost » Wed, Jul 07, 2021, 7:16 AM UTC

I used to have a camping water purifier from MSR that they developed with a company called MIOX. It ran on batteries and had a little catalyst and you put salt solution in and it fizzed and produced chlorine that you poured into your water bottles. It smelled like a pool. As long as you had batteries and salt you could make an infinite amount of chlorine.

It looks like MIOX is still around [0], they make portable units for the military and for temporary installation but I imagine this approach isn't cost effective for a permanent facility.

[0] https://www.miox.com/