[HN Gopher] How Silica Gel Took Over the World
___________________________________________________________________
How Silica Gel Took Over the World
Author : Hooke
Score : 188 points
Date : 2025-04-01 19:33 UTC (1 days ago)
(HTM) web link (www.scopeofwork.net)
(TXT) w3m dump (www.scopeofwork.net)
| Civitello wrote:
| What a perfect opportunity to link to one of my favourite candies
| https://waskstudio.com/products/sealed-fate-candy-packets
|
| Balls of hard candy shaped and packaged like silica gel!
| andrewSC wrote:
| What a fun little website!
| jonasdegendt wrote:
| Every time I stumble onto it I have to resist not buying five
| gimmicky things.
| kridsdale1 wrote:
| My favorite is the Short Sided Ruler.
|
| Perfect for April 1st.
| fuzzythinker wrote:
| Got to ask why?
| lovich wrote:
| Why not?
| fsckboy wrote:
| self explanatory, it's dessi- _can_ instead of dessi- _cant_
| buildsjets wrote:
| Why ask why? Try Bud Dry.
| neilv wrote:
| Lolimsorandom/imsoedgy types have plenty of space to work in,
| without messing with child safety.
| binarymax wrote:
| Also a perfect opportunity to link to one of my favorite comics
| https://onegianthand.com/post/188730414621/silica-gel
| stavros wrote:
| The big bags of that candy also come with an actual silicagel
| packet to keep humidity from ruining the candy, so it's always
| a fun game of "guess what's edible".
| lupusreal wrote:
| I'm earnestly surprised those are legal. Here's another idea,
| sweet fruit juice concentrate in a drain cleaner bottle. What
| could go wrong?
| pests wrote:
| How about a cleaning chemical packaged to look like fruit
| juice? Fabulous.
| Fr3ck wrote:
| Do they have candy that looks like Tide pods?
| paulgerhardt wrote:
| What a perfect opportunity to link one of my favorite podcast
| episodes https://99percentinvisible.org/article/beyond-
| biohazard-dang...
|
| Why danger symbols can't last forever.
| thaumasiotes wrote:
| > Benford was brought in to help calculate the probability
| that someone or something would intrude on the site for as
| long as it remains dangerous -- approximately the next 10,000
| years. It turns out, few things (outside of organized
| religions and ritualized traditions) last that long.
|
| What a weird thing to say. No organized religion or
| ritualized tradition has ever lasted that long.
| amiga386 wrote:
| Vsauce Michael approved!
| https://www.youtube.com/shorts/OEYqWMHyhtM
| Mistletoe wrote:
| Starting to put these in my hygroscopic fertilizers was a game
| changer. No more bricks of unusable waterlogged crap after a few
| years. You can regenerate the beads in the microwave and you can
| buy color-changing ones on Amazon that indicate their status.
| eande wrote:
| Another one of these fascinating super absorbent materials is SAP
| (Superabsorbent polymer).
|
| It is heavily used in diapers, tissues, water retention for
| plants, etc. SAP can absorb liquid up to 30-60 times its own
| volume.
|
| https://en.wikipedia.org/wiki/Superabsorbent_polymer
| dist-epoch wrote:
| I think it's more expensive, and I'm not sure it can absorb
| vapor (not liquid)
|
| It's fun that it has the same refractive index as water, so if
| you put clear ones in water they disappear. Then you ask
| someone to put their had in a bowl with them for a surprise.
| btilly wrote:
| My kids loved that stuff when they were young.
| genewitch wrote:
| Aka orbees. Also useful as a soil amendment if you have clay
| soil, it stops it from claying so much and retains water
| underground for plants.
|
| They make glow in the dark ones, which I put into a masonry jar
| with some distilled water and a drop of bleach, I light it from
| underneath with a USB LED and it glows for about an hour. Cool
| night time light.
|
| Back in the early 90s they had a different name and they were
| irregularly shaped. This was for Soil Amendment. I think it
| started with a Z.
| joecool1029 wrote:
| > I think it started with a Z.
|
| zeolite? https://en.m.wikipedia.org/wiki/Zeolite
| genewitch wrote:
| i don't think so. It was a brand name of whatever SAP they
| had decided was safe for plants to bathe in. I found some
| about a decade ago, just by asking about water retention
| crystals at an agricultural outlet. I think it's cheaper to
| buy orbees when they're on clearance, though.
| nvader wrote:
| I didn't find this in the article, so:
|
| You can "recharge" silical gel by baking in the oven at 120 C for
| a couple of hours. If you do, be careful to remove the casing
| before you do, unless it is heat safe.
|
| I have a small collection of oven safe dessicant packs that I
| keep on hand for emergency drying electronics.
| JohnFen wrote:
| I use a food dehydrator for this, but the principle is the
| same.
| nvader wrote:
| When my last phone took an unsanctioned swim, my research
| suggested that a food dehydrator is a last resort. It risks
| forcing water vapour further into the electronics of the
| system, rather than encouraging it to move out.
|
| I did find a clever solution online that tried to induce
| mechanical suction on your phone to force the vapour out, but
| it was too expensive for a one off use.
|
| In the end I had to resort to the food dryer anyway, after
| the silica gel failed to work.
| JohnFen wrote:
| I've never used it for drying wet electronics. The couple
| of times I've dunked my phone, I've just let it air-dry for
| a couple of days and it's been good.
|
| I use silca gel for storing 3D printing filament and long-
| term clothes storage.
| nemonemo wrote:
| This sounds like a great idea, but how do you keep it from
| being "drained" or hydrated?
| mrob wrote:
| I store mine in an plastic box with airtight lid designed for
| food storage.
| nvader wrote:
| Precisely this! Even so, I refresh them just before using
| them.
|
| TIL about the microwaving trick. I'll have to find out more
| about it. My concern would be the gel beads popping from
| internal pressure.
| NoahKAndrews wrote:
| If they're not getting hydrated slowly, they're not serving
| any purpose. The whole point is that water goes into them
| instead of whatever you're trying to keep dry.
| mrob wrote:
| If you're keeping them on hand for drying electronics in
| emergencies then you need to store them somewhere airtight.
| filoleg wrote:
| I think the grandparent comment meant keeping unhydrated
| during storage (for future uses of emergency drying
| electronics), not while it is being actively used for its
| intended purpose.
| wildzzz wrote:
| Immediately take them out of the oven and store in the
| smallest airtight container you have. Obviously they'll
| absorb the humidity in the container and whatever is
| introduced anytime you open it. Ideally, keep them in
| containers that have an excellent seal and minimal internal
| volume like quality ESD bags.
| thfuran wrote:
| I don't think I've ever seen an antistatic bag with a very
| good seal, and I'm not sure it's a good idea to drop
| something directly out of a hot oven into them either.
| cma wrote:
| Another option is a canning jar.
| dredmorbius wrote:
| For the quantities of silica gel typically used, a
| smaller spice or condiments jar (glass with metal lid)
| would be more appropriate for most people.
| reverendsteveii wrote:
| other people are suggesting the microwave rather than the
| oven. to my mind it seems very possible that you don't keep
| them from hydrating, you just dehydrate them on-demand.
| jonah wrote:
| In a "ziplock" bag which you have vacuumed all the air out
| of.
| singleshot_ wrote:
| Throw them in a container with some silica gel.
| jchw wrote:
| I use dessicants for 3D printing. I've heard you can dry them
| out safely by just microwaving them for a few seconds. I wonder
| if that's good enough.
| bayindirh wrote:
| You can get the ones with indicators, which change color
| according to how saturated they are.
|
| You can check the color to see whether it's time to microwave
| them, and whether they are dry once you microwaved them.
| abracadaniel wrote:
| The indicator is supposed to be toxic though. I've always
| seen warnings to never reuse that kind.
| adrian_b wrote:
| If the indicator is cobalt chloride, which is blue when
| dry and pale pink (possibly almost invisible) when wet,
| that can be toxic or carcinogenic when ingested in great
| quantities, or when you inspire a lot of dust of it, but
| it is not dangerous to handle when in compact form.
|
| It is certainly not something like a poison, where small
| quantities can have harmful effects, at least not for
| most people.
|
| Like nickel, cobalt can cause allergies in some people,
| in which case repeated exposure can have serious effects
| even in small quantities, in those humans who are
| sensitive to it.
| bgnn wrote:
| I use them in my car against condensation.
|
| The instructions on tge cover say 3 minutes at 700W in the
| microwave.
| Graziano_M wrote:
| You can just microwave them too, on low power. It's much, much
| faster and power efficient.
| mrob wrote:
| Also much harder to control. Oven drying has the advantage
| that you can set the temperature so there's no risk of
| overheating anything.
| geor9e wrote:
| I do microwave. It's pretty easy to not burn, just
| undershoot it - 10 seconds, see how hot it is, another 10
| seconds. Once it's blazing hot shake it back and forth to
| get the steam off. If it's the colored kind (white when
| good, pink/blue when full of water) it's easy to tell when
| it's good. Takes about 30 seconds all together - I recharge
| my dessicant packs before every use. Of course, people are
| welcome to spend hours doing the oven method if they want.
| I just don't personally see an advantage, unless you have
| an industrial amount of packs to recharge.
| lazide wrote:
| FYI, but some desiccant coloring agents are cancerous
| hilbert42 wrote:
| It's cobalt chloride--the same stuff that used to be used
| on those little weather indicators where a little man or
| woman would pop out to indicate whether it was going to
| be wet or dry. They usually had a spot of blotting paper
| about 2cm round soaked in it. Cobalt chloride is blue
| when dry and pink when damp.
|
| All ionic cobalt salts are toxic so cobalt chloride is
| not used as an indicator in silica gell packaged for use
| with food. That said, it's an excellent indicator for
| telling whether your silica gell is still working or not.
| lazide wrote:
| Silica gel for industrial purposes sometimes is soaked in
| it as an indicator.
| JohnBooty wrote:
| Yeah. Unless it's advertised as "food grade" and has a
| specific "Cobalt chloride free" I would def. not put it
| in food -
|
| These fit the bill. Assuming they're not straight-up
| lying or anything...
|
| https://www.amazon.com/Rechargeable-Desiccant-
| Dehumidifiers-...?
| lugvruzzle wrote:
| is there any harm in overheating silica when drying it out?
| pumnikol wrote:
| Pure silica? It's really just SiO2. It might kind of
| fragment/ burst if it has a lot of water absorbed and you
| heat it too fast. Then everything in the vicinity would
| get sprinkled with fine dust which you shouldn't inhale
| in large quantities, as it might cause silicosis.
| neilv wrote:
| Can someone speak authoritatively on how safe/unsafe it is to
| put the silica gel packets with cobalt chloride indicator into
| the oven?
|
| (By default, I've been assuming it's _not_ sufficiently safe.)
| ender341341 wrote:
| There's silica gel you can buy without cobalt chloride that I
| use for storing my 3d print filament.
| neilv wrote:
| I also do this. I'm wondering whether anyone needs to be
| warned about cobalt chloride, or it's innocuous.
| adrian_b wrote:
| Cobalt chloride decomposes only at extremely high
| temperatures and it melts only at very high temperatures (726
| degC), which could not be reached, in any case not before all
| water in the silica gel would be converted to steam and it
| would be eliminated. Even when no water is left, it is
| unlikely that the beads with cobalt chloride could absorb
| enough microwave energy to be heated at very high
| temperatures.
|
| So by itself cobalt chloride could not cause any problem.
|
| However, I have no idea whether the cobalt chloride is not
| mixed with some organic binder, to make it stick to the
| silica gel beads, which could burn in the oven, though that
| is also unlikely to happen before all water is removed from
| the gel, allowing an increase in temperature above the
| boiling temperature of water.
|
| By using low microwave power and short time, so that no
| boiling of the contained water should be seen, it should be
| possible to dry even beads with cobalt chloride.
| jdietrich wrote:
| If you're concerned, the orange/green silica gel is non-
| toxic.
| imglorp wrote:
| Practical details about the types of desiccant beads and how to
| dry them.
|
| https://www.youtube.com/watch?v=6tHInlFfMcM
| Workaccount2 wrote:
| You are better off soaking the wet electronics in isopropyl
| alcohol then trying to dry them in a bag full of desiccant.
|
| One of the things that kills wet electronics is the dried
| residue that is left behind, creating shorts. Alcohol will wash
| away the water and leave no residue after it dries.
|
| If the device has ink or glue you'd like to try to preserve,
| deionized water will mostly work too.
| lightedman wrote:
| At my work any electronics that have had a water bath or
| flux-added rework will get an ultrasonic alcohol bath and
| then a forced air drying run. Alcohol is just so damned good
| for so much.
| wkat4242 wrote:
| I totally agree though my use of it is pretty different ;)
| dieselgate wrote:
| What percentage alcohol is used?
| arcmechanica wrote:
| usually 99%
| fellerts wrote:
| I'd be very scared of IPA in an ultrasonic cleaner. Sounds
| like a recipe for a fire. Or is your machine perhaps
| designed for safe IPA cleaning?
| Retr0id wrote:
| Do ultrasonic cleaners get hot?
| actionfromafar wrote:
| Typically not (though some have heaters you can apply)
| but they atomize the fluid pretty well. The tiniest spark
| (static electricity) and some bad luck and you have the
| lid shooting into the roof and then a fire. As with
| everything, if you know what you are doing, go ahead.
| adlpz wrote:
| I've run isopropyl alcohol in an ultrasonic cleaner.
|
| It _did_ get significantly hot after a while. And smelly,
| so it was surely aerosoling (is that a word?) somewhat.
|
| I did it outdoors and away from anything that could catch
| fire because it felt rightly sketchy.
| numpad0 wrote:
| It's basically an industrial ultrasonic humidifier
| attached to the bottom of a buffet tray. And it does get
| warm.
| bradyd wrote:
| A lot of ultrasonic cleaners have a heating element.
| benjijay wrote:
| I'm scrolling before coffee and initially took your
| acronym as India Pale Ale, which would certainly be a
| different cleaning experience...
| jdietrich wrote:
| A few companies do make ultrasonic cleaners that are
| designed for flammable solvents, but they aren't common.
|
| The easiest option is to just fill a plastic food bag
| with solvent, throw your part in, seal it with a clip and
| float it in your ultrasonic bath. The bag contains the
| vapour for safety, and it's easy to switch between
| different solvents and solutions.
| 0_____0 wrote:
| That's a quite elegant solution I hadn't considered
| before.
| adolph wrote:
| That is next generation sous vide. Just controlling
| temperature is ho-hum. Getting it to just the right
| ultrasonic vibration to "cross-modulate the adipose
| frequency" is next level.
|
| And someone is already doing it:
|
| https://besservacuum.com/en/ultrasonic-food-treatment-
| machin...
| hilbert42 wrote:
| I've used both EtOH and propan-2-ol (IPA) for decades in
| ultrasonic cleaners both at room temperature and heated
| (quite warm to feel but not boiling hot) and never had a
| problem with fire.
| nyanpasu64 wrote:
| One time I tried drying a water-soaked smartphone in alcohol,
| but the alcohol got under the LCD screen and made it look
| blotchy permanently. The phone still worked but I stopped
| using it.
| nicoburns wrote:
| I think the protocol would generally be to disassemble the
| device and then clean with alcohol. Easier said than done
| with a phone of course.
| owenversteeg wrote:
| Yeah, I've had the same issue; as far as I can tell it's
| not actually the LCD itself but the backlight and the
| diffuser that end up getting screwed up. If you're trying
| to save electronics, keep the isopropanol away from the
| screen.
| hilbert42 wrote:
| _" You are better off soaking the wet electronics in
| isopropyl alcohol."_
|
| Where I am ethanol (EtOH-95%, H2O-5%) is much cheaper and
| much more readily available and works almost as well. If
| silica gel is not available, then a fan works well followed
| by a _warm_ (not hot) oven baking. Make sure the alcohol has
| essentially all evaporated first.
|
| Keep in mind that some components can be affected by both
| EtOH and propan-2-ol -- component markings, coil doping
| resins can dissolve, etc. Both alcohols are also good at
| removing solder flux resins/residues. (Oh for the days when
| freon and freon mixtures were available, component damage
| never happened.)
|
| Devices with power transformers pose special problems, best
| to dry with alcohol first (hoping enamel coatings on wire
| aren't softened), then bake in oven on warm heat for a long
| while, sometimes 24 hours or more is necessary. With
| transformers it's important that this is done as soon as
| possible after wetting.
|
| _Edit: as I 'm reminded by nyanpasu64 keep both alcohols
| away from LCD screens (likely all screens). I had a netbook
| PC and put it in a carry bag with a bottle of EtOH and it
| leaked. The PC still worked but the screen suffered the same
| outcome._
| SirHumphrey wrote:
| That may be country specific, but at least where I live,
| ethanol is much more expensive than isopropyl alcohol
| (30EUR/l vs 10EUR/l) - mostly because of dues on ethanol.
| hilbert42 wrote:
| Right, if you live where duty is applied to ethanol then
| it's expensive. In Australia, where I am ethanol is
| available as a denatured product. That is, it includes a
| very small amount (much less than 1%) of denatonium (aka
| Bitrex) which renders it undrinkable (it's the bitterest
| substance known). As such, excise tax is not levied.
|
| Here, one liter bottles of denatured ethanol are
| available in every supermarket everywhere, and up to 20
| liters available in hardware stores (at bulk rates it's
| even cheaper).
|
| For comparison, here denatured ethanol costs about $5/l
| [in US dollars] versus isopropyl at between $25 and
| $30/l.
| DebtDeflation wrote:
| In the United States, if you buy "Denatured Alcohol" at a
| big box store, it will be a toxic brew of often 50-60%
| methanol as well as smaller amounts of MEK, MIBK, and
| even acetone in addition to the ethanol. However, you can
| order "Specially Denatured Alcohol (SDA)" from various
| chemical suppliers or even Amazon. "SDA 40B 200" will be
| 99.5% ethanol with 0.1% tert-butyl alcohol and 0.0005%
| denatonium benzoate. It's what I use for camp stove fuel
| since I refuse to carry methanol in my pack with food.
| hilbert42 wrote:
| I understand the problem with purchasing EtOH in the US.
| Frankly, I consider adding MeOH, MEK, etc. to denature it
| as both dangerous and an archaic procedure. (Moreover,
| outside lab reagents, MeOH should never exist without
| denatonium, it's just too dangerous.)
|
| Some people will drink EtOH whether it's denatured with
| MeOH, etc. or with the much safer denatonium. Why blind
| or kill these people when one doesn't need to? Sure, EtOH
| will likely get them anyway but why should the State be
| their executioner?
|
| There's something awfully wrong with that I reckon.
| InDubioProRubio wrote:
| Puritan wrath, a nice mixture of hatred of ones own ant-
| existance and hatred on others not participating the
| labour camp race to the bottom, thats why?
| 0_____0 wrote:
| Typically I would dismiss this as a bit overwrought but I
| came back from overseas last week and promptly was forced
| to drive in Boston, an activity that both takes place in
| the heart of US puritanism and perfectly encapsulates
| something that is frustrating in a way that could only
| happen in a place where "it's shit, it's supposed to be
| shit, and if you don't like it, there's the door" is a
| core principle.
| hilbert42 wrote:
| Right, I was being polite, my question was rhetorical.
| 1oooqooq wrote:
| it's cheaper and the free market is regulating itself as
| god intended.
| gpderetta wrote:
| Isn't the ethanol denatured? There's a duty on that as
| well?
| hilbert42 wrote:
| It is, with denatonium hence no excise tax.
| noname120 wrote:
| Why not demineralized water instead of alcohol?
| Numerlor wrote:
| Alcohol would dry up faster, demineralised water will have
| more time to dissolve and redeposit particles. Though you
| have to be careful with alcohol as it can destroy some
| plastics
| moebrowne wrote:
| They can also be died at much lower temperatures, it just takes
| a lot longer. I dry mine by leaving them on top of a computer
| at ~35C for a week, I believe the air flow from the fans is
| important.
|
| The color indicating ones are useful so you can see when they
| are dry.
| timerol wrote:
| At what ambient humidity do you do this? Where I am we are
| having a dry day at 45% humidity today. Tomorrow it'll be
| over 90%, and it'll stay between 50% and 90% through the
| weekend. I would expect that you need a more consistently dry
| environment for this to work
| amiga386 wrote:
| https://onegianthand.com/post/188730414621/silica-gel
| FridayoLeary wrote:
| Why does it have the words DON'T EAT printed on every single
| package? you don't usually come across such warnings on other
| products.
| timerol wrote:
| Your body likes having water inside of it, and doesn't like
| having glass shards inside of it
| lovecg wrote:
| With millions and millions of those things around I'd guess
| quite a few get ingested accidentally and we don't hear of
| them causing problems. It must be pretty safe (well as safe
| as eating a small amount of sand is).
| celticninja wrote:
| https://www.theguardian.com/notesandqueries/query/0,,-18619
| 3...
| celticninja wrote:
| Actually they are quite safe to eat.
|
| https://www.theguardian.com/notesandqueries/query/0,,-186193.
| ..
| marcosdumay wrote:
| In small quantities. As somebody already pointed, your body
| likes to keep its water inside it, it also doesn't like
| when stuff carries large quantities of unmixed digestive
| fluids from one part of your body to another.
|
| They are probably quite harmful if large pieces get eaten
| in non-small quantities. Or powder in large quantities that
| are not previously mixed with a liquid. But I don't know of
| anybody that tested that.
| genewitch wrote:
| You can also ingest up to one cup of gasoline.
| celticninja wrote:
| You can ingest a litre of boiling oil.
| genewitch wrote:
| well, i hoped i _implied_ "without major injury". or so
| i've heard. I don't particularly like the flavor so i
| have avoided drinking gasoline thus far.
| AdamH12113 wrote:
| The packets look like the little salt packets that come with
| fast food, and the stuff inside looks kind of like salt.
| netsharc wrote:
| Probably because they look like candy, and they're packaged
| with food a lot?
|
| Even if not packaged with food, these sachects left on the
| table while unboxing, e.g. a pair of shoes, might entice
| kids... And it's just easier to print "DO NOT EAT" rather than
| have separate production lines for "for shoes" and "for food".
|
| Although, from the description, it seems they're perfectly safe
| (because they're inert) to eat...
| giraffe_lady wrote:
| I'm pretty sure it's just following the rules of the strictest
| food packaging laws among the places they expect them to end
| up. In some jurisdictions non-food that is directly inside a
| package along with food needs to be labeled that way. So they
| just do em all like that.
| wildzzz wrote:
| It's a choking hazard that is sometimes included in food
| packaging so it's just to cover the manufacturer since they
| don't really know what products it may end up in. Silica gel is
| non-toxic although maybe could cause some issues if you
| deliberately ate a huge quantity of it.
| madcaptenor wrote:
| Before I had kids I wondered this. But it's really telling you
| to make sure your kids don't eat it.
| mmmlinux wrote:
| I realized this week for the first time exactly why. there was
| one in my instant ramen along with its other seasoning packets.
| If not paying attention you could easily be having your noodles
| with added desiccant flavor.
| stavros wrote:
| Yep, my mother in law did.
| Ekaros wrote:
| Also used with food stuff. So just producing one SKU with "DO
| NOT EAT" saves money and doesn't really hurt in other use.
| jchw wrote:
| > That single gram of silica gel could have an internal surface
| area of eight hundred square meters--the size of almost two
| basketball courts.
|
| For us Americans, that's about 8600 square feet...and around a
| seventh of a football field.
| wkat4242 wrote:
| Yeah it's a bit of a weird way the article puts it. Measuring
| in square meters but then referencing basket ball courts which
| are almost nonexistent in Europe :). They should have used a
| football (but soccer, not the American kind) field. Though in
| that case I guess it will be a fairly small division of one too
| which makes it sound smaller than it is.
|
| I honestly have no idea how big a basketball court is.
| jajko wrote:
| What do you mean they don't exist. I see them everywhere,
| indoor, outdoor, also every single school gym regardless of
| level is also a basketball court. I've lived in 3 countries
| here east & west Europe and this is valid across different
| places and cultures.
| dustincoates wrote:
| Soccer fields don't have a standard size, however, so you're
| not going to be able to give a true comparison.
| jchw wrote:
| I'd love to say that my comment was some commentary on the
| weirdness of the units, but really, it just stuck out to me,
| and I thought it'd be funny if I treated "gridiron football
| field" as the imperial system equivalent unit to the metric
| "basketball court" unit.
|
| I rarely make comments on HN that are mostly just humorous
| and not actually intending to be on-topic... but every once a
| year or so.
| Tyrannosaur wrote:
| I don't know where you are in Europe, but from my experience
| basketball is popular in France and courts are everywhere.
| krunck wrote:
| Lets not forget the MST3k silica gel skit in:
| https://mst3k.fandom.com/wiki/MST3K_1103_-_The_Time_Traveler...
|
| https://www.dailymotion.com/video/x8hb1jh @ 00:02:00
| Animats wrote:
| Five ads and seven "subscribe" buttons, for one short article
| about silica gel.
|
| Wikipedia has a better article.[1]
|
| > You can just microwave them too, on low power... Oven drying
| has the advantage that you can set the temperature so there's no
| risk of overheating anything.
|
| It's hard to hurt silica gel itself with kitchen level heat.
| Melting point 1200C. The packet it comes in is more of a risk.
| Although there are forms with other chemicals that change color
| when humid. Also, heating wet desiccant fast enough to produce
| steam might crack the material.
|
| [1] https://en.wikipedia.org/wiki/Silica_gel
| pwg wrote:
| Ublock Origin defaulting to blocking all the Javascript by
| default and the only "ad" is the "get this newsletter" ad near
| the bottom.
| ge96 wrote:
| The word desicant is burned into my mind from this guy talking
| about building some AC system
| benwikler wrote:
| Can't see this headline without thinking of my favorite cartoon
| of all time
| https://www.reddit.com/r/me_irl/comments/sqap29/me_irl/
| benwikler wrote:
| Ah, seeing that (apparently like-minded amiga386) came here to
| post the same thing:
| https://onegianthand.com/post/188730414621/silica-gel
| xfp wrote:
| The ones in food are often oxygen absorbers instead of
| dessicants. They contain iron "sand" that is, unfortunately, not
| reusable. They're usually very flat and have a "do not microwave"
| warning on them in addition to "do not eat".
|
| (This is not to say dessicant packets aren't used in food, just
| that not all of those packets are dessicants)
| crazygringo wrote:
| Can you point to an example?
|
| Silica packets are definitely used in foods that need to be
| kept super-dry, like seaweed or nuts -- absorbing residual
| moisture that was in the product during packaging.
|
| I've never heard of an oxygen absorber used in food. A lot of
| snacks and things (e.g. all potato chips) in airtight
| containers are packaged in nitrogen so there's no oxygen in the
| first place.
|
| Are they for small-scale food production that can't use
| nitrogen? I've never encountered them in my life.
| bobsmooth wrote:
| Bacon bits, fried onions, beef jerky.
| xfp wrote:
| The Gimme-brand seaweed snacks I get contain oxygen
| absorbers. So do packages of Tillamook Country Smoker jerky
| and meat sticks.
|
| They seem to be fairly common with packages of jerky and
| other self-stable cured meats.
| numpad0 wrote:
| There are both. Oxygen absorbers are used for moist snacks,
| apparently.
| Symbiote wrote:
| I've seen these in imported Asian products, especially from
| China and Japan. Biscuits and similar dry snacks.
|
| I've never seen it for a European product.
| Uzmanali wrote:
| As a kid, I imagined silica gel was a special treat. It seemed
| like the ultimate 'DO NOT EAT' dare. I put one in my mouth,
| waiting for superpowers or disaster.
|
| Turns out, it just tasted like disappointment and regret. 10/10
| would not recommend, but at least I lived to tell the tale!
| moonlighter wrote:
| Former W.R. Grace employee: Molecular Sieve Desiccant Beads (also
| manufactured by W.R.Grace) are even more absorbent than regular
| silica gel. It's found in most double-pane windows inside the
| metal track between both panes; slowly absorbing any moisture
| over many years to keep them from fogging/going 'blind'.
|
| You can use MS to dry flowers in record time... and use it to
| quickly heat up baby food in a pinch if needed... just put a
| smaller container of food in a bigger pod filled with MS and pour
| water of the MS... it's ultra-rapid absorption of water creates
| heat as a byproduct.
| dredmorbius wrote:
| I'd just learned of (and shared a link to) a related
| technology, "getters", which similarly hold tight vacuums in
| various applications for years if necessary:
|
| <https://news.ycombinator.com/item?id=43498489>
|
| Those are used in vacuum-sealed windows and glazings (the topic
| of the post I was commenting to).
|
| There are also moisture scavengers put into cooling
| applications (refrigerators and A/C) to remove any incidental
| water from refrigerant, which I suspect operate more like your
| MSDBs.
| owenversteeg wrote:
| Getters can hold tight vacuums for several decades, even! I
| have many vacuum fluorescent displays from the 70s still
| working perfectly. As long as the getter spot is shiny and
| not white, it is holding vacuum fine.
| dboreham wrote:
| Ahhh. This explains why my glass panes go "bad" after 20-30
| years in the harsh Montana conditions we have.
| dredmorbius wrote:
| Clearly, you can just put the window in the microwave for a
| few seconds to refresh it ;-)
| jas39 wrote:
| This is sold as crystal cat litter. Very useful to put a sock in
| the car, the boat or the check-in luggage.
| yetihehe wrote:
| Careful with check-in luggage. Apparently it might be mistaken
| for crystal meth [1].
|
| [1] https://www.huffpost.com/entry/man-jailed-in-bust-of-the-
| yea...
| thaumasiotes wrote:
| "I ate the DO NOT EAT packet in my pepperoni. Am I going to die?"
|
| "Well, everyone's going to die eventually."
|
| "Everyone? Oh my God... WHAT HAVE I DONE?!?"
|
| https://explosm.net/comics/rob-pepperoni
| tim333 wrote:
| archive link
|
| https://web.archive.org/web/20250401195714/https://www.scope...
| zzbn00 wrote:
| I reuse ones I find in consumer goods by putting them into a jar,
| together with open superglue bottle(s), and putting the jar into
| fridge. Not a scientific study, but it does seem to keep the glue
| for longer then just fridge.
| Cthulhu_ wrote:
| Isn't it also because the jar is closed that the superglue
| keeps for longer? A fridge also dehydrates the air (condenses
| on the back wall in most cases).
| zzbn00 wrote:
| Maybe that would be enough. But the belt-and-braces approach
| of superglue with silica gel bags in a closed jar, in a
| fridge, seems to work well and has meant the superglue is
| still usable when I end up needing it....
| dkbrk wrote:
| CNC Kitchen put out a great video on the practical use of silica
| gel. I especially found his exploration of different methods of
| drying to be of interest.
|
| https://www.youtube.com/watch?v=6tHInlFfMcM
| THE_FORT wrote:
| This was fantastically well written. Big thank you to the author
| and the poster!
| peterarmstrong wrote:
| "That single gram of silica gel could have an internal surface
| area of eight hundred square meters--the size of almost two
| basketball courts."
|
| This reads like something from The Three Body Problem :)
| amelius wrote:
| Silica is great for removing humidity from air. But what I want
| is to remove oxygen from air, so my food stays fresh longer. Any
| clean and easy to use substance/method for that purpose?
| Luc wrote:
| Oxygen absorbers. Little paper packets of iron powder.
| dawnerd wrote:
| I think a lot of us might even confuse the two. The packets
| look fairly similar too.
| pumnikol wrote:
| Yeah don't. Like many metals, finely dispersed iron can self-
| combust on air. I'd suggest an air-tight packaging filled
| with CO2, or, if your food is susceptible to acid, N2, if at
| all feasible. Industry uses additives similar to
| hydroquinone, mixed directly into, e.g., plastics. Plenty of
| them are food-safe, but I wouldn't know where to buy them if
| you aren't a business.
| Luc wrote:
| You leave the iron powder in the packets. No need to
| disperse it, and certainly not in the air.
| iglio wrote:
| Vacuum
| chneu wrote:
| Radiolab did an amazing episode on food freshness. They talk
| about plastic produce packaging, which is a bit of a modern
| marvel.
|
| https://radiolab.org/podcast/forever-fresh
|
| Tldr: those plastic bags that salads come in are WAY more
| interesting than you think. They're selectively permeable
| membranes that only allow certain gasses in/out.
| IAmBroom wrote:
| Not mentioned by the article: 99% of all silica gel packets are
| utilized cosmetically, with no practical effect.
|
| Is your equipment shipped in non-airtight containers, like
| cardboard boxes? That silica gel will absorb all the water it can
| before it leaves the factory. It effectively does nothing after
| that.
|
| Are your silica gel packets stored in non-airtight bags? In that
| case, they're spent before they enter the packagin at all.
|
| Did you save a bunch of silica gel packets from stuff Amazon sent
| you, and use them to "dry out" your gym gear (I have known
| friends to do this). Those packets are long-since "full", and do
| nothing. (My friend: "Well, it can't hurt!" And it also can't
| help.)
|
| They aren't cordless water pumps, moving humidity out of the air
| perpetually into their contents - but that's how most people view
| them.
| spicybbq wrote:
| Is this true? Are you suggesting that manufacturers are adding
| the packets for psychological reasons? Even if they are used up
| by the time a consumer sees them, are we sure they had no
| benefit at an earlier time?
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