At what temperature does e juice vapour turn to smoke ?

[vince01]

Do any of the vets know of any experiments to determine at what temperature e juice stops producing vapour and starts producing smoke ?

I ve been able to find out that both pg and vg have similar boiling points of 188 & 190C

Thanks

 

[The Ocelot]

Do any of the vets know of any experiments to determine at what temperature e juice stops producing vapour and starts producing smoke ?

I ve been able to find out that both pg and vg have similar boiling points of 188 & 190C

Thanks

Hi Vince,

It appears your are confusing Boiling Point with Flash Point.

Boiling isn't burning, it's rapid vaporizing. If you drip water into a hot pan it will evaporate, not burn. Vaporizing occurs when a liquid is heated to its boiling point, the temperature at which the vapor pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding environmental pressure.

On the other hand, burning (combustion) is a high-temperature exothermic chemical reaction between a fuel and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed smoke.

Combustion of a liquid fuel [ignitible] in an oxidizing atmosphere actually happens in the gas phase. Gasoline is a good example. The fumes from gasoline are what ignite, not the liquid, since gasoline has a low flash point. That's why it appears to explode, since all of the gas fumes ignite so quickly.

In the US, there is a precise definition of flammable liquid as one with a flash point below 100 degrees Fahrenheit (38 degrees Celsius). Less-flammable liquids (with a flashpoint between 100 degrees and 200 degrees Fahrenheit) are defined as combustible liquids.

The Flash Point of propylene glycol
≈109 °C (228.2 °F)¹

The Flash point of vegetable glycerine
≈193 °C ( 379.40 °F)²

While some liquids may have a higher boiling point than flash point it involves more chemistry and math than I want to deal with³. Bottom line, our coils don't get hot enough to be of a concern while vaping. You may occasionally see a small flame when dry burning, but it is residual by-products that are burning, not the e-liquid.


You can see here how the gasoline fumes catch fire first and turn hot blue. This doesn't have anything to do with your question, but I think it's interesting.






1) MSDS Lyondell Chemicals
2) MSDS Gulf Coast Vapor, posted per OSHA requirement
3) FRACTION VAPORIZATION OF IGNITABLE LIQUIDS http://www.kennedy-fire.com/PDFs/FractionalVaporization.pdf

Thank you Google.

 

[Katya]

^ What she said....