Analysis of the Black Gunk on Atomizer Coils

[exogenesis]

Had a go at analysing the black crud that builds up on the atomizer coil/wick.

The original question (kinabaloo) was whether the acids that people are using to clean their atomizers
was (partly) effective due to dissolving and mineral salts present in the gunk,
thereby weakening the structure & breaking it apart, making it easier to remove (e.g. by agitation).

Used approx 20 mg nicotine with both propylene glycol (PG) & glycerol (VG),
plus a mixture of loranne flavours, this makes a jet-black, hard deposit on the coil.

XPS was used (elemental analysis using x-rays & measuring emitted electrons)

SUMMARY  
           % by atoms    % by weight
Carbon     64              49
Oxygen     22              23
Metals      8              18
Silicon     4               8
Nitrogen    1               1

Mostly oxidised organic carbon as expected,
but significantly more metals (sodium, potassium, calcium & tin) than I was expecting.

Detail
          Atomic %
Carbon      63.8
Oxygen      22.4
Silicon      4.3
Sodium       3.2
Potassium    3.1
Chlorine     1.0
Nitrogen     1.0
Calcium      0.7
Tin          0.5

Attempting to interpret the higher rez scans:
The signal for carbon appeared to be mostly coming from C-O-C (organic),
the oxygen signal half from C-O-C (organic) & half from O-C=O (organic) or CO3 (salts).


If there had been low amounts of metals, the dissolved minerals idea certainly would not have been true,
but given the 18% by weight metals seen above, it certainly is a possibility.

However it's also quite likely that most of the metals are bound or bonded with carbon,
rather than present as mineral salts, so not so conclusive I guess.
Anyway the gunk is mostly burnt (oxidised) carbon, no real surprise.

If you're interested in details :
http://www.Exogenesis.co.uk/Carbon_PeakTables.xls

 

[surbitonPete]

That's fantastic Exo.....it's funny how interesting science get's when you have a need...lol

I guess that means there isn't anything that will actually 'dissolve' the gunk??

 

[leaford]

Outstanding work, Exo!

 

[cosican]

So, with all that said,
WHAT IS YOUR SUGGESTION

1) just throw the atomizer away and use new ones??
2) or any cleaning of any sort can be somewhat effective?
3) use only specific liquids and or flavors??
4) just throw away and use a NEW one, is for me?

any advise would be helpful
thank you for all that effort

 

[surbitonPete]

So, with all that said,
WHAT IS YOUR SUGGESTION

1) just throw the atomizer away and use new ones??
2) or any cleaning of any sort can be somewhat effective?
3) use only specific liquids and or flavors??
4) just throw away and use a NEW one, is for me?

any advise would be helpful
thank you for all that effort

I am thinking we have to work along the lines of finding something that has the ability to 'break' the bond of the carbon to the coils.

 

[kinabaloo]

Exogenesis - superb, groundbreaking work.

I will need a little time to take it in and form some new hypotheses about the deposits, what happens when clean with an acid or H2O2, what might clean this better, any health considerations (re gasses that would also have been released while the decomposition was taking place) and what juice constituents might be implicated, etc

First noticeables: the chlorine is possibly due to non-distilled (i.e. tap) water that has rected to form an insoluble compound(s)? But the calcium is lower than potassium and sodium, which suggests otherwise, although some of the chlorine may have exited as chlorine gas or a volatile chlorine containing molecule (such as a chlorinated hydrocarbon; it is a reactive element).

The presence of silicon suggests plant matter; so does the nitrogen.

The tin is a real surprise. Could this possibly have leeched from solder joints? Perhpas there is a small amount of tin in nichrome wire besides the nickel and chromium; if this were the source that's a significant loss for our precious alloy.

Where has all the the hydrogen gone?

There might be a significant amount of carbides potassium carbide, sodium carbide etc, besides amorphous carbon (if any). Silicon carbide is black; not sure about the others. In saying this I am trying to account for the net color of the deposit.

Some questions

Exo - does visiual inspection / manipulation suggest the presence of plastic-like polymers in the deposit, or burnt plastic? What other forms could organics take in this high temperature environment?

Exo - the third highest peak, close to tin, is unidentified; what are the possibilities here, or it's too difficult to say? Could in fact the peak for say tin actually be for something different, a compound, or with this analysis technique that is impossible?

Exo - No signal for hydrogen - that is odd, or can the technique not identify the presence of C-H, say?

 

[surbitonPete]

I am wondering if something like adding more calcium to the juice could actually help prevent the gunk from 'coagulating' into hard lumps

 

[cosican]

Exogenesis - superb, groundbreaking work.

I will need a little time to take it in and form some new hypotheses about the deposits, what happens when clean with an acid or H2O2, what might clean this better, any health considerations (re gasses that would also have been released while the decomposition was taking place) and what juice constituents might be implicated, etc

First noticeables: the chlorine is possibly due to non-distilled (i.e. tap) water that has rected to form an insoluble compound(s)? But the calcium is lower than potassium and sodium, which suggests otherwise, although some of the chlorine may have exited as chlorine gas or a volatile chlorine containing molecule (such as a chlorinated hydrocarbon; it is a reactive element).

The presence of silicon suggests plant matter.

The tin is a real surprise. Could this possibly have leeched from solder joints? Perhpas there is a small amount of tin in nichrome wire besides the nickel and chromium; if this were the source that's a significant loss for our precious alloy.

More thoughts later.

Exo - does visiual inspection / manipulation suggest the presence of plastic-like polymers in the deposit, or burnt plastic?

WOW, I DID NOT UNDERSTAND ONE WORD OF YOUR POST
I did not do to well in my science classes in High school, but I was vaping all that other stuff back in the 70's
I am going to let you do your magic and then I am sure, you will post, exactly what to buy, to clean these little things In the meantime, I buying a bunch of atomizers
So, by the way, are you a college professor? or a nuclear scientist??

 

[latte hiatus]

This is great - thanks so much, Exo!

I'm thinking of the various chemicals automotive detailers use to remove oxidized carbon deposits from exhaust tips, and frankly I don't want any of those near my atomizer with the possible exception of Natural Orange and other citric cleaners (need to look up whether those contain hazardous materials).

 

[kinabaloo]

Pete - yes, no 'mr muscle' miracle cleaner possible. But we know that we can weaken the deposit enough by reacting with enough of it such that the rest will come off when the coil is heated afterwards. IF the cleaning is done sooner than a few weeks-ish. Over time the deposit get literally harder.

Cleaning might well not cure an atty with serious loss of performance (when this is due to coil deposits rather than simply being flooded) when it is on the older side. Even the most aggressive agents might not work then.

We are likely to propose that in addition to routine draining, either :
* a routine mild clean
* or a clean only when performance begins to diminish
* or just accept it and order a new atty to arrive in time

Later (a month or so) i expect we will determine a regime for the first option that can be put forward with confidence and clear details. For now, it is take your pick from those three.

 

[Happy Jack]

I've said it before, and I'll say it again...

YOU GUYS ROCK!!!

Thanks for the research for all our benefit!!!

 

[Idahojo]

Yes we most certainly appreciate it. Thank you. BTW I recently tried a strong mixture of Citric Acid and water on a poorly performing atomizer and it seemed to improve the performance greatly. I let it soak 24 hours and then rinsed like crazy. I don't know if it affected the stuff around the coil or just the mesh area but I definitely saw a difference.

 

[kinabaloo]

Pete - i very much doubt that adding calcium would help! Since these deposits are basically the dry deposits of the juice, and possibly also from the PG/VG, the solution would be reducing the dry deposits in juice formulations as much as possible.

There might be something that could be added to the juice that would react with the deposits or some part thereof on formation and release them as harmless gasses, but that is not even something to contemplate without knowing more exactly the compounds present; and a long-shot even then.

 

[kinabaloo]

Idahojo - yes, citric acid / lemon juice perhaps my first choice for a routine type clean over cola or vinegar - it has the strongest acid effect, is inorganic, least likely to leave its own reaction deposit, and leaves no taste.

Dry deposits on the metal wicking will cause, eventually, a harder draw (air flow) as well as reduced juice delivery to the coil so this is an importany aspect to cleaning also. And these deposits do not receive the high temperatures that deposits on the coil receive, so are far less likely to decompose and harden structurally by cross-reaction or structural realignment.

 

[surbitonPete]

Ok ......so I have pondered a little more on the idea of an additive to the juice which might be able to stop the carbon from 'sticking' and forming into hardened lumps.....and have made up a strong saline solution by adding salt crystals to water...and now I am vaping a little bit of juice mixed with saline solution.......I cannot 'taste' the salt...I didn't really expect it to vaporize. I believe it should stay behind in the gunk. (I think salt is actually supposed to be quite healthy to inhale anyway).......well only time will tell if this (probably daft) idea has any merit.

 

[kinabaloo]

Pete - and when you need to clean, just plonk in some warm water, whereupon the salt dissolves and the rest falls off with it. Hmm, understand the idea, but ...

Salt water is corrosive to steel (the metal wadding and tube) and even if it works to help with removing the deposit from the coil, it does so by making the coil get vape-reducing deposits twice as fast.

But crazy ideas help us think outside the box. So rock-on Pete! Feel a little sorry for that atomizer though

 

[schnauzer4me]

WOW, I DID NOT UNDERSTAND ONE WORD OF YOUR POST
I did not do to well in my science classes in High school, but I was vaping all that other stuff back in the 70's
I am going to let you do your magic and then I am sure, you will post, exactly what to buy, to clean these little things In the meantime, I buying a bunch of atomizers
So, by the way, are you a college professor? or a nuclear scientist??

crackin up - EXACTLY what i was thinking........

your guys are totally the bomb. i dont usually know what the heck you mean with the details but i can get the bottom line-. thank you - i love reading all the research & results. (the 70's put a hurtin on my brain cells too but didn't kill 'em all off)

 

[surbitonPete]

Pete - and when you need to clean, just plonk in some warm water, whereupon the salt dissolves and the rest falls off with it. Hmm, understand the idea, but ...

Salt water is corrosive to steel (the metal wadding and tube) and even if it works to help with removing the deposit from the coil, it does so by making the coil get vape-reducing deposits twice as fast.

But crazy ideas help us think outside the box. So rock-on Pete! Feel a little sorry for that atomizer though

ahh ....but.........my theory is that there is far too much 'oil' in the liquid for the corrosion part to be a problem....fingers crossed......lol.

 

[kinabaloo]

Nothing sticks to ceramic (i guess we've all seen the photos of gunky coil sitting in a pristine ceramic pot.

So a ceramic heater element would be ideal in new-era attys.

 

[exogenesis]

surbitonPete

not sure it proves anything about removability, it's just 'whats there' really,
also it not the most appropriate analysis method - dissolving it in a lab & wet
chemical analysis, or gasifying it & GC/MS would be better.
Adding calcium :
could make it easier to acid remove, or then maybe it might make it physically tougher,
possibly would affect the vaping 'performance' if you added too much?
It's a good idea though, adding stuff to make it clean easier, rather than just dealing with it afterwards.
Tell us how the 'salty e-liquid' goes...



cosican
my current suggestion is: try one of the existing cleaning methods
(e.g. different acids in various strengths or H2O2),
& see if it works for you. Or better still clean as regularly as you can to avoid the build-up.
(btw I write software, but sometimes I have to 'test' the new code on these machines )



kinabaloo - text block alert!
Yes, that lower amount of calcium surprised me too,
guess there's not much tap water used in liquid production.
Suspect that some of the chlorine possibly comes from acids used
during nicotine extraction from tobacco ?
Not sure about the silicon, it might even be an additive given there's so much of it.
XPS analysis can't detect hydrogen atoms (directly) cos of their simple electron shell structure.
Observing it physically forming with a x10 lens, it looks like bubbling burning toffee,
then it hardens to a hard brittle crust as it oxidises - building up layers.
Glad you noticed the ??? peak, I think its also tin as well
(which would only double the amount of tin present),
but I'm going to ask someone about that on Tuesday, cos I'm not sure,
if it's a bit too far from the known tin-compound positions.
The technique shouldn't create any chemical states, it just sees whats there,
but what's there in it's 'burnt' state is not necessarily what the liquid was originally.
Actually vaping is a cross between burning and evaporation so some of the original is probably there too.



Actually the best solution to all this is to get a piezo vapourizer/atomizer working,
maybe with a thinner e-liquid - no heating.
Contemplating getting some (or ripping out of humidifiers)
& joining in with the modding fraternity.

Thanks all for encouragment, wish I has a GC/MS