Inert gasses to prevent oxidation

Hello all!

I have a quick question on which inert gasses are best suited to backfill oil/distillate containers to prevent oxidation. I’ve seen a lot of people using nitrogen gas so that was my first thought. But, being a grow facility as well as a lab, we have substantial quantities of CO2 on site already.

The ability to use existing equipment and refill my tanks on site is definitely a big plus for the CO2. But will it give the same results? It seems to me that it will but I’m curious what the group has to say on the issue. Which gas do you prefer and why?

Thanks all!

You’d be looking for an inert gas, like Nitrogen. Cannabinoids being soluble in CO2 leads me to think it would absorb some of the cannabinoids over time, leading to some product loss. The N2 is intended to displace gas oxidizers, and the introduction of CO2 may add more oxygen molecules to the system proportionally than the ambient atmosphere would be initially.

1 Like

CO2 is not the right choice, but not because cannabinoids are soluble in it. You want something more inert. CO2 + water will give you carbonic acid. that stuff can eat away the very earth you’re standing on :wink:

It’s a neat concept, but if cannabinoids were actually soluble in CO2 gas, then CO2 extraction would not work.

My understanding is that they are soluble in supercritical CO2, and in the terpenes that are soluble in liq CO2. Drop the pressure, drop the cannabinoids. give or take.

@Jonaaronbray or @Plant2pipe could probably correct me on that.


I think you’re right on with your assessment with CO2. I was just unsure as to solubility in CO2 gas over an extended period of time, such as a back-fill and some longer-term storage.

1 Like


just not inert enough in my books.
see …eat away the very earth… link above


Nitrogen is extremely cheap.


N2 or Argon is your best bet :ok_hand:


you can use CO2. it will not react with the THC and also its purpose is to displace the oxygen that is in there already. so you would have a mix of nitrogen and carbon dioxide instead of nitrogen and oxygen. O2 is what reacts with the unsaturation in the THC molecule

Argon is heavier than air which is why it is beneficial, however more expensive than nitrogen


Ad 0.4% vitamin E maybe? It’s what we do in our labs to preserve proteins being transferred that are very oxidatively reactive and need their pigments kept in tact.

rumor has it this has been tried, and it affects the taste.

1 Like

Does anyone have any stability data (6 months/1 year) on storage in Nitrogen vs Argon? Bud or extract.

1 Like

The important question should be, what is stability like when stored under inert gas vs air, not which inert gas provides the best stability

From an engineering perspective, inert gas is inert gas. You think at room temp and atmospheric pressure that nitrogen’s triple bond would ever give a shit? Hell nah :wink:

1 Like

Agreed would be happy to find stability data on nitrogen vs air as well if anyone has this analysis on file.

If distillates made proper it won’t oxidize regardless of the gas you put in the jar. I have jars 2 years old that have been open and closed numerous times with no inert gas that have yet to oxidize.

1 Like

sort of yes, sort of no. There is a difference between nitrogen and argon from an engineering perspective whatever that means (I guess from a facile perspective)?

They are both indeed inert in this context, sure. But argon is heavier than both nitrogen and oxygen and has the property of settling over time beneath any remaining oxygen left behind during an imperfect purge. So if your BOP is “flow inert into mason jar of distillate at X L/min for 20 seconds before sealing” and an operator does this and does a reasonably good job at displacing most of the oxygen with an inert gas, whatever remaining oxygen will mix pretty uniformly with nitrogen whereas in argon the oxygen concentration will be lower at the liquid/vapor interface and higher at the top of the container because argon settles below oxygen by virtue of its density difference.

Long story short, argon offers more robust protection from oxygen but is usually a little more expensive. Both work good enough.


Sounds like a very impure product if you haven’t seen any oxidation after 2 years.


Argon is the way to go, I have had no issues with it.


Are you willing to share how you “make distillate properly?” Specifically, which parts of your SOP eliminate oxidation?


“From an engineering prospective” in this case would be something like “neglecting finer effects” :wink:

You have given a good and correct description of some finer effects.

My solution…purge violently! lol

1 Like