[HN Gopher] Electrolysis can solve one of our biggest contaminat...
       ___________________________________________________________________
        
       Electrolysis can solve one of our biggest contamination problems
        
       Author : PaulHoule
       Score  : 182 points
       Date   : 2025-12-30 18:08 UTC (1 days ago)
        
 (HTM) web link (ethz.ch)
 (TXT) w3m dump (ethz.ch)
        
       | chrisweekly wrote:
       | This looks very promising! Efficiently dehalogenizing toxins,
       | preserving their carbon "skeletons" to be repurposed for valuable
       | (nontoxic) industrial chemicals, creating NaCl (table salt) as a
       | byproduct... seems full of win to me. Here's hoping...
        
         | buildsjets wrote:
         | Benzene is quite toxic. The EPA classifies benzene as a known
         | human carcinogen for all routes of exposure. And their method
         | leaves it buried it in the soil. It is not a valuable
         | industrial chemical when it is in the soil, it is a pollutant.
        
           | zdragnar wrote:
           | Benzene is toxic, but it still has industrial uses. From the
           | article:
           | 
           | > The reactor used by the researchers consists of an
           | undivided electrolysis cell in which dimethyl sulfoxide
           | (DMSO) is used as a solvent
           | 
           | They remove the DDT from the soil into the solvent (itself
           | quite unpleasant). From there, it's pretty easy to filter out
           | the soil and clean it up. Add water and boil or freeze dry to
           | extract it back out, preferably capturing it to be reused.
        
             | MangoToupe wrote:
             | > From there, it's pretty easy to filter out the soil and
             | clean it up.
             | 
             | "Cleaning" soil is an interesting concept. At what point
             | does it just become dirt? Presumably some of the nutrients
             | will remain, but it seems like this would sterilize it.
             | 
             | Dirt still has use, of course, but soil is expensive to
             | produce for a reason.
        
               | zdragnar wrote:
               | Well, cleaning in this case would be removing the
               | remaining DMSO, which is probably not too desirable to
               | have in your soil.
               | 
               | Considering the existing DDT contamination, ending up
               | with dirt that needs to be fortified with compost is
               | hardly the worst trade-off.
        
             | modo_mario wrote:
             | This all sounds like it would be many manyfold more
             | expensive than just digging it all up, gathering it all
             | togheter and putting it into some quarry or so that doesn't
             | let much if any seepage happen.
        
               | zdragnar wrote:
               | I don't think it is intended to be commercially viable on
               | the basis of benzene production alone.
               | 
               | Rather, it is a more permanent solution compared to
               | sequestration, where the benzene production offsets the
               | cost.
               | 
               | If, as they plan, it can be done on-site, that would also
               | eliminate transporting the soil and avoiding accidentally
               | spreading it elsewhere, which is appealing as well.
               | 
               | Sanitary landfills (the sort that prevent seepage) are
               | not exactly cheap either, and pose an ongoing risk in
               | that the DDT is always there, waiting to get back out.
        
         | guenthert wrote:
         | Render me surprised as there is no Na in DDT.
        
       | CheeseFromLidl wrote:
       | How does this work on a practical level? Do you scrape the soil
       | to a depth of a foot and submit it to electrolysis or is the soil
       | washed and the sludge then processed? How many grams of halogens
       | does this recover per square acre of contaminated site? Does this
       | sterilise the site?
        
         | awakeasleep wrote:
         | I think itd be meant for the facility that uses the halogenated
         | compounds in the first place, integrated into their process.
        
           | CheeseFromLidl wrote:
           | a process that can be used *on site* to render environmental
           | toxins such as DDT and lindane harmless and convert them into
           | valuable chemicals - a breakthrough for the *remediation of
           | contaminated sites*
        
         | coryrc wrote:
         | Today we scrape however many meters deep of soil and haul off
         | to a landfill. I assume you'd scrape it up, run it through
         | something to pull out everything bigger than a pebble. Wash the
         | pebbles, the rinse water goes with the soil through the
         | cleaning process.
         | 
         | Certainly what comes out of the machine will not be living.
        
           | worthless-trash wrote:
           | I guess it'd be a good time to add some bacteria and life
           | back into the soil that in a controlled manner.
        
         | talkingtab wrote:
         | The real practical and immediate help would be ground water
         | contamination. How many bad chemicals now permeate the water
         | supplies around farming communities. Can this be used to treat
         | the drinking water supply?
        
         | LorenPechtel wrote:
         | Yeah, this makes no sense.
         | 
         | It sounds like it could be used to decontaminate a waste
         | stream, but how do you select out the offending materials from
         | a site?? What magic breaks halogenated bonds while leaving
         | others (which are easier to break) alone? And how does the
         | solvent work?? Remember, teflon only became practical when they
         | found a solvent for it--and it's the solvent that's the real
         | problem. Teflon is non-reactive enough for the body to pretty
         | much ignore, the solvent (which of course isn't 100% removed
         | from the final product) has one reactive spot and is a problem.
         | They've tried to hide behind a game of musical chairs, using
         | "different" solvents, but the dangerous part of the molecule is
         | unchanged as that's what's needed to do it's job. A longer or
         | shorter inert tail makes it "different" from a legal
         | standpoint, not meaningfully different from a toxicity
         | standpoint.
         | 
         | Why am I thinking scam?
        
           | zdragnar wrote:
           | DMSO is a pretty common solvent. It's still nasty stuff, but
           | easy to clean from a sample.
           | 
           | Take a bunch of contaminated soil, wash with DMSO, filter out
           | soil, wash again, take all of that and electrolyze it.
           | 
           | Take the soil, dilute with lots of water and boil in a
           | chamber with a fractionating column / distillation setup to
           | reclaim the last of the DMSO.
           | 
           | I'd be surprised if this was in any way economical, but it's
           | the cheapest way to permanently get rid of DDT, and the
           | production of benzene and other hydrocarbons is a nice side
           | benefit to reclaim some of the cost.
        
             | gucci-on-fleek wrote:
             | > It's still nasty stuff
             | 
             | I've only ever personally used DMSO in chemistry labs, but
             | Wikipedia [0] makes it look pretty safe: it claims that it
             | has a higher LD50 than ethanol and that it's been FDA
             | approved for human usage, so I wouldn't call it nasty. Now,
             | I wouldn't really _want_ to drink it because the side
             | effects and taste sound pretty unpleasant, but it appears
             | that it would be safe to do so.
             | 
             | [0]:
             | https://en.wikipedia.org/wiki/Dimethyl_sulfoxide#Toxicity
        
               | zdragnar wrote:
               | DMSO readily absorbs through your skin, meaning it is a
               | great carrier for pretty much anything else that you
               | don't want in you.
               | 
               | At the scale of "washing tons of soil to remove DDT" it'd
               | be quite unfortunate if something went wrong and tons of
               | DDT tainted DMSO got dumped into the wild.
        
           | potato3732842 wrote:
           | >Why am I thinking scam?
           | 
           | It seems scam adjacent because a high proportion of other
           | stuff written in the same tone by the same types of people is
           | a scam. The researchers don't write these puff pieces
           | generally and the people that do spend the rest of their day
           | writing "not technically a lie" type inflated corporate
           | newspeak puffery that are basically "we're actually doing the
           | customer a factor by charging more for less" tier lies.
           | 
           | It's also not unlikely that the experts involved provided a
           | list of possible use cases and "making benzene from 3rd world
           | dirt" was way down it and they had no idea the writer would
           | lead with it.
        
         | jjk166 wrote:
         | The soil is mixed with water to create a slurry which is then
         | passed through filtration units which are sensitive to
         | particular chemicals. Now the soil is fine but your filtration
         | media is highly contaminated.
        
         | pkphilip wrote:
         | It could be used to decontaminate open water bodies as well as
         | ground water. We have ways of producing electricity cheaply
         | enough these days and so using that electricity to perform
         | electrolysis makes sense - - even if it needs to be done only
         | during times of the day where there is good sunlight.
        
         | lrasinen wrote:
         | Way more than a foot, but that's the general idea.
         | 
         | There's a soil remediation project near my workplace (former
         | railway depot). They've dug up several meters deep by now.
        
       | philipkglass wrote:
       | This article doesn't link to the primary research. It's
       | referencing a Spark Award granted this year for work from 2024
       | and 2021. Here are the relevant articles:
       | 
       | "SCS Foundation News and Announcements 2025"
       | 
       | https://www.chimia.ch/chimia/article/download/2025_885/2025_...
       | 
       |  _Persistent Organic Pollutants (POPs) are highly recalcitrant
       | and toxic compounds that pose a profound threat to ecosystems
       | across the world. One of the most notorious representatives of
       | this class of chemicals is hexachlorocyclohexane (HCH) - a known
       | human carcinogen - a specific isomer of which was used as the
       | insecticide Lindane._
       | 
       | ...
       | 
       |  _In 2021, the groups of Morandi and Waldvogel disclosed a
       | vicinal dihalide shuttle reaction under electrochemical
       | conditions, with which HCH could be fully dechlorinated. In the
       | present work, instead of transferring chlorine to another
       | molecule, we sought to sequester it as an innocuous inorganic
       | chloride salt, which is preferable for large-scale application._
       | 
       | Here's the free-to-read Accepted Manuscript version of the
       | earlier 2021 publication:
       | 
       | "Merging shuttle reactions and paired electrolysis for reversible
       | vicinal dihalogenations"
       | 
       | https://ethz.ch/content/dam/ethz/special-interest/chab/organ...
        
       | CGMthrowaway wrote:
       | DDT is still sprayed today, indoors, in Africa and Asia to
       | control for mosquitos, including in India.
       | 
       | https://www.sciencedirect.com/science/article/pii/S254251962...
        
         | user_7832 wrote:
         | As an Indian... I had no idea. I've seen fumigation a lot right
         | from childhood (kids used to run _after_ the fumigation man to
         | inhale that fog), with that sweetish smell it had. Of course it
         | 's possible it was pyrethroids... not like they don't cause
         | allergic reactions either haha welp
        
         | frontfor wrote:
         | To clarify, it's not "Africa and Asia". Only India, South
         | Africa, and Zimbabwe are still using DDT actively.
        
           | throwaway290 wrote:
           | The paper says a bunch of countries don't use DDT _for
           | malaria control_ but it doesn 't say if they still use DDT in
           | agriculture. They used to use it for pest control growing
           | coffee
        
       | hosh wrote:
       | Dr John Todd has figured out and demonstrated a method to
       | remediate DDT-contaminated water without the use of electrolysis,
       | or other energy inputs. He was able to decontaminate one of the
       | top superfund sites. The method is broadly versatile, and
       | requires even lower tech than electrolysis. His methods can also
       | sequester heavy metals. It involves introducing organisms across
       | all of the kingdoms so that they self-organize on the
       | contaminant.
       | 
       | More narrowly, Paul Stamets has worked a lot on mycroremediation
       | -- remediating with fungi.
        
         | JumpCrisscross wrote:
         | > _Dr John Todd_
         | 
         | ...who is this? This guy [1]?
         | 
         | [1]
         | https://en.wikipedia.org/wiki/John_Todd_(Canadian_biologist)
        
           | hosh wrote:
           | That is the dude.
        
         | CGMthrowaway wrote:
         | >Dr John Todd has figured out and demonstrated a method to
         | remediate DDT-contaminated water ... It involves introducing
         | organisms across all of the kingdoms so that they self-organize
         | on the contaminant.
         | 
         | So... he invented the ocean?
        
           | hosh wrote:
           | Biomimicry, not invention. He reasoned that the DNA is a vast
           | library for transforming molecules from one to another, and
           | therefore, ecosystems are capable of breaking down
           | pollutants.
           | 
           | In practice, there are multiple vats. The first stage has
           | algae growing, which sequesters the heavy metals. The next
           | stages follow other kinds of ecosystems, such as organisms
           | from swamps. He will mix samples from multiple ecosystems
           | that normally don't mix so that some kind of novel, self-
           | organizing ecosystem can form around the pollutant.
           | 
           | Then it is measuring and monitoring the contaminants. With
           | the superfund site, he was tracking presence of the top ten
           | pollutants on the EPA list. However, he also shows how people
           | can use much simpler, non-industrial tests -- using samples
           | from say, uncontaminated lake water nearby and use a
           | microscope to see if the water being treated will kill those
           | microorganisms. This allows for remediation to be executed by
           | people who don't have access to labs, but still need a way to
           | test their water.
           | 
           | A much simpler version of this that follows the same design
           | principles is capable of local, onsite treatment of ordinary
           | black water.
        
             | odyssey7 wrote:
             | Likely not what you're describing, but this hypothetical is
             | what came to mind.
             | 
             | Consider if organism A consumes organism B in a symbiotic
             | way. E.g., organism B makes berries.
             | 
             | Then, we engineer A to seek out and consume DDT, perhaps by
             | making DDT delicious or fragrant to A.
             | 
             | Unexpected consequence: organism B evolves to produce
             | berries that are absolutely redolent with DDT.
             | 
             | This might happen centuries later, due to the DDT-phillic
             | genes outlasting the presence of artificial DDT in the
             | environment, or it could happen much sooner, or it might
             | never happen. Hard to know. "Life finds a way."
        
       | metalman wrote:
       | short, sweet, got the zam. for toxic waste sites (superfund), and
       | land fills this checks all the boxes. Given that many of the
       | older developed areas that have contaminated sites are also
       | building out solar power, and pushing electricity prices into the
       | negative, I believe that this could be set up to run full tilt,
       | when power was cheap, and idle when it is expensive.
        
       | buildsjets wrote:
       | Wait up. They propose to convert DDT trapped in the soil to
       | benzene trapped in the soil? Is not benzene also a toxic and
       | persistent soil pollutant (it is) where the typical remediation
       | is to excavate the bad soil and landfill it? (it is)
       | 
       | https://www.waterboards.ca.gov/water_issues/programs/gama/do...
       | 
       | There was an old lady who swallowed a fly, she didn't know why.
        
         | jjk166 wrote:
         | They're not leaving it in the soil. The benzene is extracted as
         | a useful byproduct.
        
           | buildsjets wrote:
           | Yes, they are leaving it in the soil. Prove me wrong with
           | data. It says nothing at all about extracting the waste
           | benzene they created from the soil, neither in the linked
           | article nor in the complete paper, which i did read. The
           | paper specifically describes an in-situ process. If it were
           | economically beneficial to extract benzene from contaminated
           | soil for industrial use, we would already be doing that with
           | the tens of thousands of existing benzene contaminated sites,
           | not creating more of them.
        
             | irjustin wrote:
             | > neither in the linked article nor in the complete paper,
             | which i did read.
             | 
             | I'm having trouble finding the paper, can you link please?
        
               | buildsjets wrote:
               | Courtesy of another poster down-thread.
               | 
               | https://ethz.ch/content/dam/ethz/special-
               | interest/chab/organ...
        
               | irjustin wrote:
               | Isn't this the 2021 paper?
               | 
               | I can't find the 2025 which this article is supposed to
               | be improving upon that work?
               | 
               | Or are we just resurfacing 2021 work all together?
               | 
               | [Edit]
               | 
               | Yes that is the 2021 paper, but this new announcement is
               | supposed to improve that process but I can't find any
               | sort of paper other than the Spark Award 2025
               | announcement[0]
               | 
               | [0] https://www.youtube.com/watch?v=NcMTOI25yb8
        
             | zdragnar wrote:
             | It's in the article:
             | 
             | > The reactor used by the researchers consists of an
             | undivided electrolysis cell in which dimethyl sulfoxide
             | (DMSO) is used as a solvent
             | 
             | They move the DDT from the soil to the solvent, which is
             | the medium for electrolysis, not the soil itself.
        
             | jjk166 wrote:
             | > A much lower Lindane-soil ratio of 1 w%, where Lindane
             | was _extracted with the reaction solvent prior to the
             | degradation_ , also afforded good yields for both benzene
             | (76%) and dichloride (76%, Entry 4, Fig. 4D). This
             | alternative _pre-extraction protocol_ acts as a further
             | proof-of-concept which might help the design of larger
             | scale remediation processes in which undesired soil
             | contamination with electrolyte and Mn catalyst can be
             | prevented. Interestingly, the large-scale feasibility of an
             | extraction approach has been demonstrated by the successful
             | treatment of ca. 70,000 tons of HCH contaminated soils in
             | the Netherlands in a _full-scale soil washing plant_ ,
             | which achieved HCH removal efficiency of more than 99.7%
             | (42).
             | 
             | Emphasis added
        
         | zdragnar wrote:
         | The DDT is soluble in DMSO, so it is already possible to
         | separate from soil.
         | 
         | The problem has been that the DDT isn't really useful, so
         | you're still left over with DDT tainted DMSO. Hence, most
         | cleanup efforts focus on sequestration of soil.
         | 
         | The electrolysis step creates benzene and other hydrocarbons,
         | making a useful byproduct. This means there's a better
         | incentive to treat it rather than store it.
        
           | sargun wrote:
           | So, you're essentially washing the soil in DMSO, and DDT is
           | more soluble in DMSO? -- curious, what does it take to wash
           | all that soil?
        
             | zdragnar wrote:
             | Assuming it doesn't break down under electrolysis, the DMSO
             | can be recovered, so you only use as much as you can
             | process at a time.
             | 
             | It is apparently used in some battery chemistries, so I'd
             | expect losses to be pretty low if the equipment is set up
             | well.
        
         | scythe wrote:
         | Benzene is far more degradable than DDT. In fact the primary
         | reason benzene causes cancer is because the human liver _can_
         | metabolize it, producing the reactive carcinogen oxepin. It
         | doesn 't always degrade fast enough to prevent toxicity to
         | humans or animals, but it doesn't last forever.
        
       | ggm wrote:
       | Uses DMSO (by-product of paper production processes) as solvent.
       | It's pretty nasty. All industrial processes wind up with nasty,
       | and this may be swapping a less tractable and nastier problem for
       | a well understood DMSO handling problem.
        
         | buildsjets wrote:
         | DMSO is a solvent that is is absorbed directly through the
         | skin. Jello Biafra was wrong though, if you mix it with lemon
         | juice and pour it on your hand, you will not sense the taste of
         | lemons in your mouth. You will taste garlic. Try it and see.
         | 
         | https://genius.com/Dead-kennedys-dmso-lyrics
         | 
         | I'm not sure what happens when you mix it with LSD. Again, try
         | it and see.
        
           | PaulHoule wrote:
           | Back when diclofenac + dmso was rx-only and crazy expensive I
           | tried making my own formulation with ibuprofen and dmso for
           | back pain hoping it wouldn't tweak out my stomach. According
           | to what I read, ibuprofen would be very well absorbed with
           | dmso.
           | 
           | After applying the ointment I got an upset stomach in minutes
           | so yeah.... It was well absorbed.
           | 
           | https://pmc.ncbi.nlm.nih.gov/articles/PMC3141840/
           | 
           | https://my.clevelandclinic.org/health/drugs/21230-diclofenac.
           | ..
        
           | tingletech wrote:
           | When I worked for Bill Atkinson's sister, Dr. Kathy Atkinson,
           | at UCR in high school, I was involved in a DMSO leak. Dr. A.
           | was a microbiologist, but botanists worked upstairs. I guess
           | DMSO is used a lot in botany, and they let an experiment boil
           | over and DMSO got into the HVAC air return and then into the
           | whole building. Smelled like garlic, and I turned bright
           | pink. We had to evacuate. I also tasted garlic for a day or
           | so. Nowadays you have to be 18 to get a job in a UC Lab.
           | 
           | You could get DMSO and ketamine at the vet supply store back
           | then in the 80s. I heard of people ingesting acid via DMSO in
           | that time frame, but it could have been an urban legend. It
           | was a horse area and DMSO was used with horses to get stuff
           | deep into their legs or something like that.
        
         | gucci-on-fleek wrote:
         | > Uses DMSO (by-product of paper production processes) as
         | solvent. It's pretty nasty.
         | 
         | Copying my comment on another subthread [0] here:
         | 
         | I've only ever personally used DMSO in chemistry labs, but
         | Wikipedia [1] makes it look pretty safe: it claims that it has
         | a higher LD50 than ethanol and that it's been FDA approved for
         | human usage, so I wouldn't call it nasty. Now, I wouldn't
         | really _want_ to drink it because the side effects and taste
         | sound pretty unpleasant, but it appears that it would be safe
         | to do so.
         | 
         | [0]: https://news.ycombinator.com/item?id=46442253
         | 
         | [1]: https://en.wikipedia.org/wiki/Dimethyl_sulfoxide#Toxicity
        
           | ggm wrote:
           | A solvent which is tractable for complex waste reduction, and
           | skin absorbed and would presumably carry those contaminants
           | into the body.
           | 
           | But yea, I overrated it's nastiness.
        
       | amkharg26 wrote:
       | PFAS contamination is one of those problems that seems
       | insurmountable given how persistent these chemicals are. The fact
       | that electrolysis can break down the carbon-fluorine bonds is
       | genuinely exciting.
       | 
       | What's particularly interesting is the potential for on-site
       | remediation. Traditional methods often involve excavating
       | contaminated soil or pumping and treating groundwater
       | indefinitely. If this can be scaled cost-effectively, it could
       | transform cleanup efforts at industrial sites and military bases.
       | 
       | The key question is economic viability at scale. Energy costs for
       | electrolysis can be significant, and PFAS contamination is often
       | widespread. Would be curious to see lifecycle analysis comparing
       | this to current remediation methods.
        
         | istjohn wrote:
         | This does not treat PFAS.
        
       | kawfey wrote:
       | Before reading the article, I guessed the headline was alluding
       | to the popularity of Hypochlorus Acid as a sanitizer, made from
       | electrolysis of slightly acidic salty (NaCl) water. I had a kid
       | and the algorithm led me to discovering a brand of in-home
       | electrolysis generators, and after a fair bit of research on
       | safety and efficacy I've been using it quite a bit.
       | 
       | Technically it solves contamination problems too.
        
       | krbaccord94f wrote:
       | Key point is this shift, which takes place from ideology to
       | institutions. Ele-ctrolysis is the procedure of isolating ions
       | from substrate. Running electrical current in water, which tends
       | to separate the molecules as the inverse, being the addition of
       | O2 to H20 in creating the peroxide or H2O2 distillation.
        
       ___________________________________________________________________
       (page generated 2025-12-31 23:01 UTC)