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Author: Subject: Dissolving Neodymium Magnet in .08M HCL solution - Possible?
Summa
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[*] posted on 15-10-2016 at 03:36
Dissolving Neodymium Magnet in .08M HCL solution - Possible?


Hey guys,

So lets say I have a few 5mm in diameter, spherical shaped Neodymium magnets. The magnet is an alloy: Nd2Fe14B
Its zinc plated.

I also have simulated "stomach acid" using .08M of HCL solution.

What would if I drop a few of these magnets into the solution?

My prediction:

1) The zinc plated coating on the magent, only a few microns thick, would dissolve within a few minutes.

2) The Neodymium magnet would dissolve give the presence of Iron in the magnet alloy.

Question:

Assuming i leave these magnets in the "stomach acid" for an hour, how much would they dissolve? would mass decrease by half? what about their "pull force" as measured by magnetic flux?

If 1 hour in .08M of HCL solution won't do anything to the magnets, I will forego the experiment.

Unfortunately I need 6-7 weeks to secure samples of zinc coated Neodymium magnets thats why i am turning to the board for help and expediency.

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[*] posted on 15-10-2016 at 06:20


These magnets are usually plated with nickel, are you sure your are zinc plated?



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[*] posted on 15-10-2016 at 11:20


Quote: Originally posted by crystal grower  
These magnets are usually plated with nickel, are you sure your are zinc plated?


Most definitely. I can get anything almost anything from China:

https://www.alibaba.com/product-detail/Countersink-neodymium...

I just need rough estimates of reaction time at .08M. Trying to stimulate teh transit time in the stomach and whether a 5mm spherical Zinc coated will dissolve or not.
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[*] posted on 15-10-2016 at 20:47


I feel like this would be really, really difficult to measure accurately, without a lot of other variables taken into consideration. You would need to know the surface area of the magnet, as well as the surface area of the reaction. If you're testing to see if the magnet is going to completely dissolve in your stomach bile within a certain time, you would need to account for the places where the magnet is reacting. Does it get dissolved evenly, or unevenly. You also have to remember that bile is not cold, its in the body and pretty warm right? So you have to think about heating your solution too.




In short this is a lot of integration, and physical chemistry. To help you I would need more information.
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Summa
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[*] posted on 18-10-2016 at 02:47


Quote: Originally posted by Fidelmios  
I feel like this would be really, really difficult to measure accurately, without a lot of other variables taken into consideration. You would need to know the surface area of the magnet, as well as the surface area of the reaction. If you're testing to see if the magnet is going to completely dissolve in your stomach bile within a certain time, you would need to account for the places where the magnet is reacting. Does it get dissolved evenly, or unevenly. You also have to remember that bile is not cold, its in the body and pretty warm right? So you have to think about heating your solution too.




I understand.

The surface area of the 5mm magnet would be:

r = 2.5mm
4*pi*2.5^2 = 78.5mm^2

The surface area of the reaction? I would assume its uniform all over the sphere in the HCL solution?

"Transit time" (the time it takes for food to travel through your system) is a complicated. But it usually leaves your stomach between 2-4 hours.

Solution will be heated to 98.6 Farenheit.

This is a very important experiment and with real life applications.

Right now magnets have been banned in some countries due to ingestion and how they can harmfully come together inside you. All the magnets that were banned have been Nickel (Ni) plated.

I did research and Ni doesn't react with dilute HCL. So if a Zinc plated 3mm/5mm magnet corrodes completely OR corrodes "enough" within 2 hours of HCL .8M solution - I have solved a real world problem.

By "enough" I mean to be below 50 kg^2/mm^2. The magnetic flux.

I have already ordered my HCL solutions and has shipped:
Hach 1481253 Hydrochloric Acid Standard Solution, 0.10 N, 1 L

If anyone can at all assist or can opine, please. I am very grateful.



[Edited on 18-10-2016 by Summa]

[Edited on 18-10-2016 by Summa]

[Edited on 18-10-2016 by Summa]
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[*] posted on 18-10-2016 at 03:14


The goal is to make a Neodymium that resists corrosion enough while being handled and exposed to air, but that quickly degrades in your stomach.
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[*] posted on 18-10-2016 at 05:29


Letting the Fe dissolve in one stomach or especially a child's is a deadly. I recently became aware of accidental induced lethal doses of iron in children after consuming too much of an iron supplement.

Preventing the iron from dissolving for sufficient time prior to inducing vomiting is likely a better path to avoid fatalities.

Zinc is too readily dissolved in dilute acid, or even boiling water will form Zn(OH)2.

Many transition metals are toxic.

Try thick rubber or seal the magnet in clear thick plastic or some other acid resistant resin. A good idea would be to coat the encased magnet in disagreeable tasting compound.
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[*] posted on 18-10-2016 at 09:27


Quote: Originally posted by AJKOER  
Letting the Fe dissolve in one stomach or especially a child's is a deadly. I recently became aware of accidental induced lethal doses of iron in children after consuming too much of an iron supplement.

Preventing the iron from dissolving for sufficient time prior to inducing vomiting is likely a better path to avoid fatalities.

Zinc is too readily dissolved in dilute acid, or even boiling water will form Zn(OH)2.

Many transition metals are toxic.

Try thick rubber or seal the magnet in clear thick plastic or some other acid resistant resin. A good idea would be to coat the encased magnet in disagreeable tasting compound.



How much is too much? Iron supplements are concentrated. The danger isn't from the Iron diluting. The danger comes from the magnets pinching together and creating necrotic tissue. The silent nature of this hazard is what prompted the Fed to ban the sale of magnets.

"Preventing the iron from dissolving for sufficient time prior to inducing vomiting is likely a better path to avoid fatalities."

-This is just speculation and doesn't get to the heart of the matter. You are trying to foresee a problem that currently is not an issue.

"Zinc is too readily dissolved in dilute acid, or even boiling water will form Zn(OH)2."

-Yes that is true. Also its the Zinc Oxide that offers the layer of protection as well. I am curious if the dilute HCL is enough to corrode the Zinc Oxide and the Zinc.

"A good idea would be to coat the encased magnet in disagreeable tasting compound."

-Not according to the federal government. In this case bitterants are not a sufficient deterrent to ingestion.

I am resolute in my goal in trying to make a magnet that is semi-protected when used but quickly degrades in a stomach. Unless you can show the actual LD that would result from ingesting a few of 3-5mm magnets, your answer is speculation.


[Edited on 18-10-2016 by Summa]
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[*] posted on 18-10-2016 at 09:44


Well, as long as you don't swallow more than one magnet, you'll be fine. :D

(Unless you get an MRI scan.)




As below, so above.

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[*] posted on 18-10-2016 at 11:03


What I mean about reactive area would be, does the reaction cause a layer to prevent further reaction? I'll work on some sort of integration later.. don't hold your breath, idk if I can get to it today.
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[*] posted on 18-10-2016 at 11:50


So I have done a little math here to find out how much Nd2Fe14B magnets ingested would be lethal for a kid with weight ~20Kg (44lb).
Content of Nd, B, and Zn plating was considered negligable because they shouldn't cause far as much harm as the major component of neo magnets - iron (and rather FeCl2 produced by reaction of Fe with HCl in stomach).

LD50(FeCl2) = 0.984g/kg [rat, oral]
D(Nd2Fe14B) = 7.5 g/cm3
M(Nd2Fe14B) = 1081.125g/mol
M(Nd2B) = 299.295g/mol
Content of Fe in the magnet = 72.32%
Magnet = sphere
r = 0.25cm
V = 4/3*π*r^3
V = 0.06545cm^3
m = 0.49g
m(Fe in 1magnet) = 0.355g
n(Fe) = n(FeCl2) = 0.00636mol
m(FeCl2) = 0.806g
0.806 = LD for 0.819kg
LD for 20kg = 24.42

So, app. 24 magnet spheres (5mm in diameter) would be lethal for a child weighting 20kg. It could mean that if someone eat a couple of these magnets, it would be acceptable to digest them IMO.






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[*] posted on 18-10-2016 at 11:57


LOL



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[*] posted on 18-10-2016 at 12:05


But you also have to keep in mind that magnets just aren't supposed to be eaten. If you eat a knife, you will most likely seriously hurt yourself. Should be knifes banned because of that? ;).

[Edited on 18-10-2016 by crystal grower]




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[*] posted on 18-10-2016 at 12:28


Here is one source to quote (link: http://www.cdc.gov/mmwr/preview/mmwrhtml/00019593.htm )

"Although a toxic dose of elemental iron is 30 mg/kg, and a fatal dose is typically more than 250 mg/kg, ingestion of doses as low as 60 mg/kg have resulted in death"

So, the employed LD50(FeCl2) = 984 mg/kg [rat, oral] for rats is off by a factor of 16 for 60 mg/kg and 33 for 30 mg/kg. Apparently, human babies aren't as tough as rats pound for pound.

This doesn't make me comfortable as it implies 1 or 2 magnet spheres (5mm in diameter).
-------------------------------------

For the record, I recommended 'encased' magnets coated with a bitterants. This is not a statement that bitterants alone are sufficient deterrent to poisoning. I still recommend the use of bitterants as it may, in practice, limit the likelihood of multiple magnet injestion.

[Edited on 18-10-2016 by AJKOER]
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[*] posted on 18-10-2016 at 12:51


Quote: Originally posted by AJKOER  
Here is one source to quote (link: http://www.cdc.gov/mmwr/preview/mmwrhtml/00019593.htm )

"Although a toxic dose of elemental iron is 30 mg/kg, and a fatal dose is typically more than 250 mg/kg, ingestion of doses as low as 60 mg/kg have resulted in death"

So, the employed LD50(FeCl2) = 984 mg/kg [rat, oral] for rats is off by a factor of 16 for 60 mg/kg and 33 for 30 mg/kg. Apparently, human babies aren't as tough as rats pound for pound.

This doesn't make me comfortable as it implies 1 or 2 magnet spheres (5mm in diameter).

I know rat isn't an appropiate comparsion to a human baby, but frankly, I really haven't expected such difference. I'm sorry I've made this mistake.
Still, here arises a question, let's say LD for Fe = 30 mg/kg and LD for FeCl2 = 60mg/kg. Which number is more important if the metal is eaten and thus converted to FeCl2 in stomach?

[Edited on 18-10-2016 by crystal grower]




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[*] posted on 18-10-2016 at 13:32


Iron just doesn't dissolve very fast in the stomach. Those spheres will exit the stomach nearly intact.

One study showed that a double edged razor blade took 24 hours to lose 37% of it's mass in stomach acid. Razor blades are VERY thin in the first place, so the depth of the corrosion is quite small, and 24 hours is a LONG time for something to remain in the stomach. (If you don't believe me, eat a large bowl of corn without chewing it, and time how long it takes for you to see it again, and that's the time for the entire sojourn in the digestive tract, the stomach transit is much faster)
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[*] posted on 18-10-2016 at 14:05


To come up with a standard, I suspect the legal jurisdiction the product is sold is important. For example, in China even a single death by a local distributor may be too much. See http://www.businessinsider.com/chinese-white-collar-criminal... . It may be wise to avoid certain jurisdictions.

Do you design to meet the low 30 mg/kg standard defined as toxic or something higher?

Next, package sizing, limiting the number of magnets, has to be determined. The use of bitterants could expand package sizing.

I would assume only half of a small magnet is likely dissolved in the stomach. But my knowledge of how much more could be leaching out prior to a full exiting of the body is limited.

Assuming eventually a single sucessful lawsuit awarding damages of a likely amount X, is it even possible to achieve a profit given pricing limitations?

Some good news, you can still quote the standards based on rats and enact better. Lawyers, in my bias opinion, are too arrogant to ever assume that rats are that much biologically superior to them!

[Edited on 18-10-2016 by AJKOER]
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[*] posted on 18-10-2016 at 14:23


I like the way you guys think. But alot of this stuff just misses the point entirely and currently given the market conditions, is inactionable.

1) The number 1 thing that matters...is being able to sell in the US - legally. Right now that means nullifying the existing argument on the ban of magnets. That's it.

2) There is a federal ban. You CAN'T SELL NEODYMIUM MAGNETS BELOW A CERTAIN SIZE TO ANYONE.

3) The main reason for this ban was the type of injuries: Silent Killing. Both teenagers and kids would ingest these magnets and they would have only mild stomach symptoms. Doctors and people would not come about the problem very easily. That surreptitious deadly injury is what it was so fucked. They were pinching your intestine together, mummyfying the tissue in between.

All my efforts and research will be to defeat this argument. I've ordered the first batch to sell to Europe. It cost me 10k USD. In my next batch I want to market hard to the US.

If other issues come up like possible "iron-poisoning", there is policy precedent for attacking these issues. For example, not selling to anyone below 18+. Clearly labeling that its not a toy. You have things like gasoline, mercury, wood thhiner, actual harmful shit that is being sold constantly. These are all poisonous and are not banned - because of policy and protocol. Granted the marketing of the magnets would have to change, but there would not be a federal ban.




[Edited on 18-10-2016 by Summa]
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[*] posted on 18-10-2016 at 14:55


You're missing the point entirely. The number 1 thing that matters is that the magnets won't dissolve in the stomach.

The magnets wont dissolve in the stomach.

You just wasted 10,000 USD. (assuming you're actually telling the truth), because the magnets won't dissolve in the stomach

The magnets won't dissolve in the stomach.

You just ordered a bunch of custom magnets that have no advantage to them whatsoever, because the magnets won't dissolve in the stomach.

The magnets won't dissolve in the stomach.


Oh, by the way. Did I happen to point out that the magnets won't dissolve in the stomach?

Well if I didn't, then allow me to point out here that the magnets won't dissolve in the stomach.

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[*] posted on 18-10-2016 at 15:10


And the danger of small magnets is that they screw up the peristaltic process by which material is passed along the digestive tract. That and the fact that they are easily ingested. Kids have died and that pretty quickly. Holding out for quick dissolution for the short period of time that they are in the acidic region of the gut is a bit foolish.

IOW, not only will magnets not dissolve in the stomach (thanks for that insight and clarity, Maroboduus), they will not dissolve in the duodenum and intestine. Instead they will pinch together and lock up the tract with quick necrosis at the point of contact.


If you wanted a more productive but similar project to invest your next 10K, look at button batteries that degrade quickly in the gut. Some work has been done in this area but there is room for further developments.




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[*] posted on 18-10-2016 at 18:52


Quote: Originally posted by Maroboduus  
You're missing the point entirely. The number 1 thing that matters is that the magnets won't dissolve in the stomach.

The magnets wont dissolve in the stomach.

You just wasted 10,000 USD. (assuming you're actually telling the truth), because the magnets won't dissolve in the stomach

The magnets won't dissolve in the stomach.

You just ordered a bunch of custom magnets that have no advantage to them whatsoever, because the magnets won't dissolve in the stomach.

The magnets won't dissolve in the stomach.


Oh, by the way. Did I happen to point out that the magnets won't dissolve in the stomach?

Well if I didn't, then allow me to point out here that the magnets won't dissolve in the stomach.



Relax.

I can still sell them as the market is worldwide, and the ban is not worldwide.

Its only in the US where they is an outright federal ban.

The factory in China would not let me secure a "small sample" so I said to hell with it. If they are just as expensive as the nickel plated ones, i'll order them anyway.

I wouldn't act on this if I didn't have my data. Obviously the way I am selling them is profitable and I have an edge, so I sourced them.

[Edited on 19-10-2016 by Summa]
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[*] posted on 18-10-2016 at 18:56


I don't have much contact with the regular world, and for good reason.

i detect alot of naysayers. and why things go wrong. and things just...can't be. Frankly, its annoying and low income.

I don't care for any of that. I am here to solve a problem and will throw everything I can at it. To hell with everything else.

anyway. I will post my results when I get the HCL. I'll take in a sample of the zinc.

Just to be clear. Its not dissolution I am after. Its being below the magnetic flux of 50 kg^2/mm^2.
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[*] posted on 18-10-2016 at 19:14


Quote: Originally posted by Summa  
Quote: Originally posted by Maroboduus  
You're missing the point entirely. The number 1 thing that matters is that the magnets won't dissolve in the stomach.

The magnets wont dissolve in the stomach.

You just wasted 10,000 USD. (assuming you're actually telling the truth), because the magnets won't dissolve in the stomach

The magnets won't dissolve in the stomach.

You just ordered a bunch of custom magnets that have no advantage to them whatsoever, because the magnets won't dissolve in the stomach.

The magnets won't dissolve in the stomach.


Oh, by the way. Did I happen to point out that the magnets won't dissolve in the stomach?

Well if I didn't, then allow me to point out here that the magnets won't dissolve in the stomach.



Relax.

I can still sell them as the market is worldwide, and the ban is not worldwide.

Its only in the US where they is an outright federal ban.

The factory in China would not let me secure a "small sample" so I said to hell with it. If they are just as expensive as the nickel plated ones, i'll order them anyway.

I wouldn't act on this if I didn't have my data. Obviously the way I am selling them is profitable and I have an edge, so I sourced them.

[Edited on 19-10-2016 by Summa]


I am an avid collector of magnets, and let me tell you those zinc plated magnets won't last every long in just day to day use. Even the Ni-Cu-Ni-Cr coated magnets start to corrode after a while of playing. Your zinc magnets will likely fall apart soon after you start using them.
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[*] posted on 19-10-2016 at 00:25


Quote: Originally posted by Deathunter88  
Quote: Originally posted by Summa  
Quote: Originally posted by Maroboduus  
You're missing the point entirely. The number 1 thing that matters is that the magnets won't dissolve in the stomach.

The magnets wont dissolve in the stomach.

You just wasted 10,000 USD. (assuming you're actually telling the truth), because the magnets won't dissolve in the stomach

The magnets won't dissolve in the stomach.

You just ordered a bunch of custom magnets that have no advantage to them whatsoever, because the magnets won't dissolve in the stomach.

The magnets won't dissolve in the stomach.


Oh, by the way. Did I happen to point out that the magnets won't dissolve in the stomach?

Well if I didn't, then allow me to point out here that the magnets won't dissolve in the stomach.



Relax.

I can still sell them as the market is worldwide, and the ban is not worldwide.

Its only in the US where they is an outright federal ban.

The factory in China would not let me secure a "small sample" so I said to hell with it. If they are just as expensive as the nickel plated ones, i'll order them anyway.

I wouldn't act on this if I didn't have my data. Obviously the way I am selling them is profitable and I have an edge, so I sourced them.

[Edited on 19-10-2016 by Summa]


I am an avid collector of magnets, and let me tell you those zinc plated magnets won't last every long in just day to day use. Even the Ni-Cu-Ni-Cr coated magnets start to corrode after a while of playing. Your zinc magnets will likely fall apart soon after you start using them.


If that solves the current problem at hand, making a 5mm sphere that degrades to being below 50kg^2/mm^2 of the magnetic flux when in the stomach, so be it.
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[*] posted on 19-10-2016 at 00:31


Quote: Originally posted by Maroboduus  
Iron just doesn't dissolve very fast in the stomach. Those spheres will exit the stomach nearly intact.

One study showed that a double edged razor blade took 24 hours to lose 37% of it's mass in stomach acid. Razor blades are VERY thin in the first place, so the depth of the corrosion is quite small, and 24 hours is a LONG time for something to remain in the stomach. (If you don't believe me, eat a large bowl of corn without chewing it, and time how long it takes for you to see it again, and that's the time for the entire sojourn in the digestive tract, the stomach transit is much faster)


https://www.ncbi.nlm.nih.gov/pubmed/9283866

The 1997 said 63% of mass gone. So it had 37% left.

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