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.