[pcm81]

If we are talking about indigestible products which can be used in multiple industries including food, what is the better, stricter type to buy? For example: propylene glycol or Vegetable Glycerine.  I use them to mix up ejuice for my friend, trying to get her to quit smoking. I have the 99.9% pure versions in gallon jugs from Amazon; are these versions of substances pure enough to use in place of food grade? Are food grade versions pure enough to use in place of 99.9% versions for chemistry applications as organic solvents or precursors etc?

Thanks ahead

[chenbeier]

First propylenglycol CH₃CHOHCH₂OH and glycerine HOCH₂-CHOH-CH₂OH are not the same substances. So you cannot compare them even they have similar behaviour.

From the puritiy it depends is it made for medicine, drug, etc. or technical application. You have to know which byproducts inside. But I would never use a technical product to use it for food or for using at humans or animals.

In the opposit it depends which application you need. (Analysis, synthesis, etc.)

[pcm81]

First propylenglycol CH₃CHOHCH₂OH and glycerine HOCH₂-CHOH-CH₂OH are not the same substances. So you cannot compare them even they have similar behaviour.

I realize that. ejuice is a mixture of the two, so i use them both recongnizing they are not the same thing.

From the puritiy it depends is it made for medicine, drug, etc. or technical application. You have to know which byproducts inside. But I would never use a technical product to use it for food or for using at humans or animals.

In the opposit it depends which application you need. (Analysis, synthesis, etc.)

The reason why i am curios about purity, is because "food-grade" are not marked as 99.99999 pure. From what i understand they might only be 99% pure but the remaining 1% has to be not hazardous to health. Which brings me to the question about 99.9% or 99.99% pure "chemical supplies". Should i expect that the remaining 0.1% or 0.01% be heavy metals or strong oxidizers (F-) hence making there 99.9% and 99.99% chemicals not suitable for digestion?

Is there such a thing as 99.99% pure food grade stuff? I assume if there is, then 99.99% pure food grade stuff be usable for "home chemist" applications in place of industrial grade chemicals as well.

[pcm81]

I have 99.9% food grade propylene glycol and 99.7% food grade Vegetable Glycerine. Which i use for making of ejuice. Just wondering what if anything i should watch out for if i use them for "home chemistry" rather than ejuice.

[DrCMS]

Making food grades is more about keeping things out that are harmful to people but may not show up in the assay testing.

[Corribus]

Food grade also likely includes consideration of the equipment on which the substance is manufactured (including lubricants, and so forth, used), other substances manufactured in the facility, and the materials used to package it, etc.