Road Salt? Bah! New Roadway Material Promises A Better Solution To Snow And Ice

If you’ve ever lived somewhere it gets properly cold, you’ll know that winter’s icy grasp brings the inevitable challenge of keeping roadways safe. While road salt and gritting have long been the go-to solutions, their detrimental environmental impact and the potential for infrastructure degradation are well-documented.

However, a game-changing new development might just offer a brighter, greener solution. Just imagine it—roads that stay ice free without requiring regular attention. 

Rethinking Road Salt

Put this stuff in asphalt, and you’ve really got something. Credit: Research paper, ACS Omega

The environmental hazards posed by chloride-based salts are significant. When these salts are washed off roads, they can contaminate nearby water sources. Furthermore, the repeated application throughout the winter months causes wear and tear on the roads and induces nasty corrosion on vehicles and infrastructure. There’s a reason cars in snowbelt regions rust so much faster, after all. And while road salt does serve its purpose of melting ice, once a fresh layer of ice forms, drivers are back in peril until salt trucks make their rounds again.

To address these concerns, many municipalities have embarked on a mission to formulate a safer alternative. Solutions include everything from byproducts from sugar beet refining or ethanol production processes. Recently, though, researchers from China’s Hebei University of Science and Technology have been working with an environmentally-friendly, chloride-free acetate-based salt. As per the research paper, not only is this salt kinder to our planet, but it’s also less corrosive, making it gentler on vehicles and infrastructure. Moreover, its efficacy in lower temperatures is a significant advantage over traditional solutions. Where traditional sodium chloride becomes ineffective as a deicing agent at around -10.9 ºC (12.3 ºF), the homemade sodium acetate solution used by researchers had a far lower freezing point of -23.5 ºC (-10.3 ºF).

The visual difference on the ground was stark: the asphalt with the special additive remained ice and snow free under conditions where an untreated road was completely covered. Credit: Research paper, ACS Omega

Building on this breakthrough, the scientists combined the acetate-based salt with various compounds including a surfactant, silicon dioxide, sodium bicarbonate, and blast furnace slag. The idea was to allow the blast furnace slag to act as a porous carrier for the acetate salt, while the sodium bicarbonate acted as a corrosion inhibitor. The surfactant was used to increase the absorption of the porous carrier, while the silicon dioxide was used to  disperse the materials more evenly. The mixed slurry was dried and crushed, with the combined powder subsequently encapsulated in a polymer solution, leading to the creation of microcapsules that could be incorporated directly into road asphalt. The concept was simple: including the microcapsules in the road surface directly would let the microcapsules slowly release their acetate salt content over time, keeping the roads ice free.

The newly developed asphalt was subsequently tested in real-world conditions on a highway off-ramp at the Sizhuang Toll Station of Beijing-Xiong’an highway.

The results of this experiment were nothing short of remarkable. The revamped asphalt not only continuously melted falling snow but also lowered the freezing point of water dramatically from -2.5 ºC (27.5 ºF) to a chilly -21 ºC (-6 ºF) on the material’s surface. In the winters of 2021 and 2022, the test section of road could be seen to outperform the neighboring regular asphalt, with almost no snow removal required in light snow conditions. In heavier snows, the snow and ice layer on the road was generally thin enough to be penetrated by regular traffic, avoiding the major loss of grip typical of a more resilient ice layer. If that wasn’t impressive enough, lab tests suggest that a slab of this innovative pavement, at just 5-cm (2-in) thick, could continuously release its stored acetate salt for an astonishing seven to eight years, ensuring roads remain clear throughout multiple winter seasons. That’s a significant improvement over previous stored-salt-release systems that exist..

As cities and countries grapple with the dual challenges of ensuring road safety and minimizing environmental impact, this new asphalt mixture might just be the solution we’ve been waiting for. The prospect of roads that can actively fend off ice for years without the need for frequent, ecologically harmful salt applications is truly a tantalizing one. Those sick of seeing their cars rot away in record time would likely also appreciate a better solution than good old sodium chloride. Watch this space, and consider petitioning your transport authorities for better ice-resistant roads in future.

Banner image: “October Snow” by Nicholas_T.  Thumbnail image: “DSNY salt truck” by Chris Hamby.

68 thoughts on “Road Salt? Bah! New Roadway Material Promises A Better Solution To Snow And Ice

  1. As a resident of a “winter city” this would be a welcome change. Even if the mixture ends up being too expensive for widespread use, I think it’d be handy at the lead-ups to intersections or even just if you could incorporate it into the lane markings so you don’t get someone driving down the middle of two lanes on the days it snows!

  2. “…lab tests suggest that a slab of this innovative pavement, at just 5-cm (2-in) thick, could continuously release its stored acetate salt for an astonishing seven to eight years…”

    In other words, in the real world, it will last just a couple of seasons before salt trucks need to start making regular trips over it again. And unless they plan to strip/add another 2 inches of impregnated asphalt over every road every 2-3 years, this will only show benefit to the newest roads being laid down (most cities can barely afford the time to fill potholes, let alone resurface entire roads!).

    Progress, but not nearly enough to be useful yet.

    1. It not that cities can’t afford to fill potholes, it’s that all the relatives of powerful people hired to do that job cannot be made to actually work.

      The process is called patronage. An organization delivers votes, in exchange they get no-show jobs. Old as the hills.

      At the start of Covid, NYC’s transit department was found to have twice as many checks being cut to ’employees’ as they had jobs being attended (not done).

        1. In the UK, councils are funded to maintain the roads, not just replace them. They don’t. And in fact, they simply rely on the balance of cost of repair vs cost of insurance claims for damage and most times it just lands on the insurance side. I’ve reported huge pothole damage (bent suspension, ripped tyres) and been told to fill in an insurance claim and seen the same pothole unfilled for a further 3 years.

          1. You lucky… ( / yorkie)

            In the USA the government in charge of the pavement isn’t responsible for damages. Can’t normally be sued, like anybody else with land and pavement.

            If you pay far in excess of the damage in lawyer bills, then maybe. Nobody even tries. Game is obviously rigged. Deliberately obviously.

        2. City governments are typically overfunded. They don’t replace roads either. Except ‘sort of’ they replace paved roads with gravel ones (by ignoring them).
          Or run decent schools. Or maintain honest police forces. Or keep the fire engines in good repair. But some people insist more money will fix it. Disproof in one example: DC’s public school budget and results.

          City government can and do ‘just raise property tax’. Eventually everybody with money moves to the burbs and the city is left hollow and rotten. DC is just on the federal tit, hence is living demo that money can’t fix this mess.

          Completely typical for USA east coast/rust belt, west coast same but different, earlier in process.

          They always fund the jobs for the mayors friends and family. Priorities are clear.

          The trollest urban futurist prediction I’ve seen: ‘All cities in the world will become Detroit! Is inevitable!’ That’s how you troll for views!
          Not bitching: “All cities should be Amsterdam!’ I digress.
          Gotta admit they both work.

  3. The stated parameters make it clear that this isn’t (at least not yet) a viable solution. The effect doesn’t last long enough (most roads last longer than 7 years) and I would bet money that the material makes the asphalt degrade faster as well.

    1. Or, probably a lot simpler, don’t lay the road flat but with a slope to the outside. And make car with their left wheels shorter than their right wheels. If the snow can’t stick, the water can’t freeze, you have solved the issue.

  4. Furnace slag ? So potentially toxic heavy metals potentially released…
    Polymer fiber ? more nanoplastics…
    Ionic Sodium Acetate ? less corrosive is still rust-creating agent. And as a coating, it can be released all year long, not only in winter.

    Who thougth it was a good idea ?

  5. If the sodium from sodium acetate production comes from sodium chloride anyway aren’t you just shifting the harm? What is happening to all of that chlorine, is China dumping it into water or the atmosphere?

  6. Salt accures naturally, and very common. Basically free, except transporting. Desalination of seawater, typically dump the salt back in the ocean, unless they can find a market for it. Most places only salt as needed, not every time it snows…

    1. “”only salt as needed” means residual salt on the roads … which is every bit as bad as needing to salt every time it snows. I grew up in Minneapolis and salt on the roads is horrible stuff that rots out the fenders and rocker panels of a car in as little as two years.

  7. There are a million of these papers every year. Take some commodity chemical, make it micro-nano-whatever-structured, blend it up with some other commodity chemical, and call it something fancy. It never works. You’d think they’d learn eventually (the people writing the research grants, that is).

    This is just putting road salt (sodium acetate is already used for this, it’s just expensive) inside of microplastics and mixing it with the pavement. Salt inside the road instead of on the road, big whoop. When the salt washes out (probably quickly, if they ever actually use this stuff) (they won’t) they’ll just have to put more salt on top, like we already do. It’s all so tiresome.

  8. And when the salt had been depleted, the fancy stuff has to be excavated and replaced with new, which is very disruptive to traffic and probably tons of carbon dioxide throughout the process.

    Also, can the now excavated material be recycled easily? If not, then that basically renders this project a no-go.

  9. The lower freezing point is great. When I lived in upstate Central NY, they’d often use salt on the roads when it was too cold, and the snow/ice would soften during the daytime and freeze at night, giving a nice slick ice layer, which often got powder snow blown on top of it.

  10. Wait a couple more years and it’ll be obsolete. Who needs to clear snow, when there’s no such thing as snow. Unless the billionaires are going to get away with their plans to block out the sun.

    1. Or more freeze thaw cycles. A good upper Midwest winter starts with a freeze in November and the temperature swings from 20F on warm days to -40F in February. A warm winter goes into the upper 30s repeatedly.

  11. interesting read, but looks a bit problematic as pointed out above.. of course I’ve had more problems with road melting.. always fun as kids to go write on the Bitumen on a hot summer day..

    1. Same here. I read these sort of HaD weather-related articles not because they affect me but because it gives me an insight into what people in other parts of the world have to deal with, how they solve them, and the agreements/disagreements this causes.

      1. Those of us in MinneSNOWta don’t have to put up with things that others have to contend with, such as termites, fire ants, typhoons, venomous Australian snakes…

  12. I used to see ads for a liquid called Bare Ground. When sprayed on asphalt or concrete prior to snowfall, it supposedly caused the snow to melt and it lasted for quite a while.

    I wonder what was in it?

    1. I found the products you were talking about at, but they’re basically liquid salt pre-applied with a sprayer (same as you might salt the walkway the night before the snow), and claim to prevent 2-3 inches of snow buildup. Some of their products are safer, or innovative (they take their liquid ice-melt and turn it into a gel, then fill tubes like a sock so you can throw it up on the eave of your roof to melt ice-dams), but I didn’t see anything that would last beyond a single snowfall without needing reapplication. It’s a cool idea (no pun intended), but all of these sodium-based solutions (ok, that one might have been intentional) require the mineral to mix with the water to decrease the melting point below the current temp, meaning the sodium/mineral is a consumable. The idea as stated in the article is basically that suspending the mineral in plastic slows the consumption, with the assumed goal being that it is consumed slowly enough to be able to afford to remove/replace it when it loses a certain level of effectiveness (though the cost/benefit analysis would have to include comparisons of cost of salting road normally, maintaining equipment, fuel, etc, as well as the normal rate of replacement, and the increased maintenance cost of repairs from salt damage). That said, it may well be that the road could be serviceable and capable of removing/preventing snow & ice for 5 years before the effectiveness decreases significantly, and the city/county then uses traditional salting techniques for another 5 years, then replaces the road- there are ways for a non-perfect solution to still be cost-effective.

    1. Are you trolling or ignorant? Trucks and buses also need ice free roads, not just passenger cars. Ban those too and every building needs to be build next to train stations, airports, harbors, helicopter platforms or tram stops.

      1. Stuff just magically appears when you order it. Why would you ever leave home? All of us could just sit at home thinking new revolutionary pronouns and thought controlling in social media waiting for the government cheese to roll in and using the sweet sweet pure electricity from the wall outlets to charge the phone. Understanding reality is for chumps and fuck cars, right?

    1. Yes, it is, if you live in Finland or somewhere else where spike tires are legal. For us in moderate parts of Europe salt is necessity. Also, snow on road is ok if temperature is well bellow freezing, but if it is close to freezing temperatures, it melts when cars pass over it, and then freezes again. Result is ice, not snow on the road. That said, I really love drifting on the nice snow when I get a chance, and wife is not with me in a car… :-D

    2. The salt helps turn the snow into a slush, which is far easier to for the snow ploughing trucks to flip to the side than powdery snow. That, and heavy transportation can stay on the roads better when there isnt constant black ice.

  13. Just learn to drive on snow and ice, slow down and accept that winter is a thing. No need to flood the world with salt and grit, just buy the right tyres and chains if needed and move on with your life. (Yes, I live somewhere with snowy winters and yes I drive a RWD sports car year round).

    1. Clearly you do not live somewhere where there is significant snow or paved roads.

      Chains destroy pavement and cars, and necessitate constant management because they are more slippery on dry pavement than even summer tires. Putting them on once in a while is feasible, but installing and removing them every week is stupid.

      Plowing and “salt and grit” is necessary to ensure emergency vehicles can go around as close to normal speed as possible for the biggest fraction of time possible. Accelerating other traffic is just a side-effect. Once snowing stops, then you start clearing roads for real, and that is never done by melting.

  14. I’m happy not to have to salt where I live, but I feel like if you want to talk about chloride salts, you need to mention calcium chloride. When it comes to freezing point depression, it can peak at about -60 F rather than -6F. It isn’t hard to get, even though rock salt is cheaper and they both have similar downsides.

  15. If we were really serious about saving the earth from global warming we’d build less roads and allow less cars one the road. Around here they replace asphalt roads after about 30 years of service. Hard to justify replacing road surfaces every 2-8 years especially when it costs more.

    1. Thing is, up near the arctic circle, sheitstains like norway, sweden, finland, russia etc, the idiots build sizable towns, evne cities, which need heavy transportation, which chew up the roads in the spring thaw with all those potholes just caving in from the constant 18 wheeler traffic needed to keep the lemmings and their offspring happy in their rat race.

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