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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

#71

Post by [deleted] »

lugged wrote: post #61
perihelions wrote: post #37

Earlier quoted context omitted.

If I've understood correctly, the denominator being compared against isn't a "best available alternative" treatment solution of H2O2. It's against the concentration that's an " equivalent amount "-- which is actually a pretty dilute concentration (for H2O2), that *isn't* effectively bactericidal. > "...are over 10^7 times more potent than an equivalent amount of preformed hydrogen peroxide..." Per fig. 2(c,d), the "c…

> 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…

[deleted]

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

#72

Post by graycat »

WOW, is this thread treading on thin ice in July? Uh, it is apparently well established that public commentary, e.g., in the mainstream media (MSM), 100% must NOT include chemical formulas or meaningful uses of ratios, proportions, percentages, or scientific, chemical, or microbiological terminology, yet post after post in this thread are in flagrant violation! As I recall, ratios and proportions are from somewhere above the third grade and some of the rest of the topics go up even to, horrors, high school science courses!

To add to the transgressions, this thread is discussing the content of a peer-reviewed paper of original research about some tricky, detailed parts of chemistry and microbiology.

Intelligent discussion and content? Horrors!!

Stand aside as 99 44/100% of media comes tumbling down like that condo recently did in Florida? Maybe!

Ah, that's Hacker News for you; no chance of seeing such content, such flagrant transgressions, in the MSM!

Uh, I'm not complaining, you understand! Not complaining at all!

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

#74

Post by cratermoon »

icegreentea2 wrote: post #14
slownews45 wrote: post #5

Anytime you read things like 100,000,000 times more effective - you should be asking, what was the numerator or denominator in this. Or are they just describing some tiny part of the system. For example, normally you need to filter, do settling for sediment etc - how did they solve all this? Given the orders of magnitude involved here a 5 MGD plant could produce 500 trillion gallons per day of "commercial approach" w…

The specific measure appears to be in CFU/mL of E. Coli in their test sample before and after. As you suspected, this does not include filtering or settling, just clearing out bacterial contamination. I haven't read the paper yet (paywall)- just looked at their supplementary data. The increased effectiveness appears (guessing here a bit) to be in terms of bacteria load reduction given similar concentration of bacteri…

I'm curious how it does vs Giardia, Cryptosporidium, and Legionella

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

#75

Post by pstuart »

ArkanExplorer wrote: post #49

One of the biggest pollutants now in water are PFAS, microplastics, and other hormone disruptors. How to we get rid of those without needing to rely on expensive multi-stage filters that need to be replaced every 4 months?

Dean Kamen teased us with such a solution, but still waiting for lower cost/available units to become available: https://en.wikipedia.org/wiki/Slingshot_(water_vapor_distill...

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

#76

Post by permo-w »

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.

this is poor logic. imagine two disinfectants, A and B, both kill 90%+ of known bacteria. imagine that you need 1 part per billion for A to be effective and 10 million parts per billion for B to be effective.

“Better” does not necessarily mean “kills a higher percentage of bacteria”

By the way, this isn’t a comment on the article itself in any way, simply a comment on the logic of your comment

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

#77

Post by cratermoon »

pitaj wrote: post #47
kapp_in_life wrote: post #33

Earlier quoted context omitted.

Is hydrogen peroxide "good enough" such that it doesn't matter? Like saying I'm 10 million times less likely to drown watering a lawn than I am washing a car isn't important, because the odds of either happening is vanishingly small.

The point is that you can use 1/10,000,000 the H2O2 than you would otherwise for the same amount of sanitation.

What if I could get equally good sanitation using ZERO h2o2?

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

#79

Post by poorjohnmacafee »

[edit: commenter is right, the paper abstract rendered as "107" not "10^7" in browser, will leave followup question]

Since it's a challenge to separate the products/byproducts in catalytic reactions that are homogenous/liquid phases, how would this setup achieve separation post reaction exactly? Anyone know?

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

#80

Post by shkkmo »

poorjohnmacafee wrote: post #79

[edit: commenter is right, the paper abstract rendered as "107" not "10^7" in browser, will leave followup question] Since it's a challenge to separate the products/byproducts in catalytic reactions that are homogenous/liquid phases, how would this setup achieve separation post reaction exactly? Anyone know?

I think you are missing the exponent in 10^7
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