I am stumped.
I have given someone some of my distillate and the last two times he is running into oxidation problems. When he keeps my distillate in the fridge after a while it begins to oxidize. After being out of the fridge for a while the oxidation seems to disappear. When terps are added there doesn’t appear to be any oxidation problem. The only thing I’ve done different lately is used tap water instead of RO water because my RO filtration broke down. My water is in the low to mid 8s pH. My distillate usually tests at 99 or greater percent total cannabinoids but only in the low 90s for THC. Now okay I get things can oxidize but how the fuck does it come back?
You sure your pH meter is calibrated and correct?
I calibrate mine everyday before use
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add some nitrogen or argon to the jar or pull a vacuum on a mason jar
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Yeah I calibrate my pH meter with three different buffer Solutions
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You use new solution everytime right?
This will be treating the symptoms and not the problem and it definitely does not give any explanation as to what the hell is going on… I mean how can it swing back and forth?
Yes sir
Theres gotta be something in the water then thats causing the oxidation to occur faster then normal,
Whatee you using doe pH down?
I was not adjusting the pH at all.
But I’m still mystified as to how can it go back and forth in color?
Not sure, i do know that alkaline conditions cause quinone to form which is the oxidation layer on top of distillate
I think it’s Viscosity issue. When your distillate is cold, it has very low viscosity and consequently, little to no thermodynamic current. This allows a very thin layer on top to oxidize, but refraction makes it look more red. When warmed to room temp, the oil can flow and it’s easy to mix the oxidation layer intro the rest of the jar with minimal discoloration. That’s my theory at least…
At anything below 73°f my distillate is rock hard at anything below 68°f maybe 69°f my distillate will actually shatter if it’s hit… I mean it looks like broken glass.
Initially I thought the same as you that when it’s slightly less viscous it blends the oxidized layer with the rest of it and thus making it less visible but the stuff from 3 months ago went pretty dark and then came back to almost water clear with slight tint to it.
My experience with COLD concentrates is that they are a bit more solid - and that surfaces get discolored on that partial solid. And then when they are room temperature - they are a bit less solid. And when they are a bit less solid things dissolve back into each other.
So… perhaps you have gravity and thermodynamics to thank for these changes?
A terrible example of past work. Red Ring of Death on Carts - all facing up in the box. Turn the carts over for a few days - red ring of death goes away. Overall the cart is now subtly darker than it was before - but less pronounced so you cannot tell in the same way.
Same thing goes for starting with slightly darker material - takes longer to notice the oxidation.
Same thing goes for mixing the darker material in with the lighter material.
Is it still oxidized? Yes! But can your EYES tell, perhaps not.
Sometimes the best thing to do with a discolored product in the fridge is to warm it up in your pocket (or your dashboard…or I suppose an oven…). The chemical compounds have still changed, but aesthetically you cannot tell (or at least most people cannot tell…) you could do a color refractor on it and probably see that there is a slight change from A to B - even if our human eyes cannot tell. And you could always run a cannabinoid assay test on it, and see the oxidized cannabinoids.
If you wanted. 
I have seen this many times - especially when you are changing the crystal lattice just a bit. Remember oxidation means the MOLECULES are moving around. Let them move around a little bit more and bam things are mixing.
Especially since you can still see that there is a slight change in tint.
You could also consider that you may or may not have different kinds of light when you are looking at this stuff. And exposure to different kinds of light can also cause these kinds of reactions.
I don’t think you have to wonder about some magic happening in the jar. You already know what’s up and others have seen this too. It doesn’t look “rock hard” in your photos… but then how can I tell how hard things are in photos…
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I had done some runs of bio that sat in a barn for a year and a half in totes into disty for a friend one time. No matter how many times I tried to distill it, it looked perfect in the head but then after it cooled down it was red as fuck.
Thinking the same way, I first tried shifting the pH down, thinking it was due to oxidation and that made the entire batch way worse of red, couldn’t even see through it anymore.
Then I re-did the whole batch and brought it up to around pH 7 and that took all of the red out and left with a rather nice gold end product.
It is well known that the oxygen in the headspace is what causes it to turn dark red and a nitrogen atmosphere can prevent it. But it must first be neutral before you can shift the pH or else you might strip the acids from the crude.
Now with acidic molecules, you can strip the hydrogen from the -COOH and replace it with a metal like sodium -COONa (once solvent is evaporated). This is a purple molecule and is a water soluble salt form of the cannabinoid (ultra hygroscopic). Which if you are using basic media can be pulled out of solution and left stuck on the media.
This is where basic CRC can strip THCa/CBDa from solution and is why you want the pH of the media to land near neutral.
To test: put an equal portion of each media in proportion to the mass in the column in water and use pH probe to detect changes. Typically I will use 1g per 100ml or 1%. You can also blend the media in proportion to the total mass and take a sample from that mixture.
But also, you want to flush the CRC column because the acidic’s flow slower than neutrals and terpenes. Especially when it is cold - then you can isolate the acids, which is how I first isolated CBDa back in 2020. I have seen where people forgot to do the flush and nearly all of the acids were getting tossed with the media because it seemed like there was nothing in it because it was all powdery when they took it apart and clear solvent flowing through at the end of the run - but unless it has had enough solvent pushed over it to remove the acids from the column (think of it as basic column chromatography), then the acids could still be residing in the media.
Pure THCa and CBDa are powdery without the neutrals which the neutrals come out of CRC first. So you want to run plenty of solvent over the CRC to ensure you have gotten all of the product out of the media. But also, you want a neutral mixture so that you do not cause isomerization of the terpenes or loss of the acids.
Personally, I 100% believe it is a pH issue. But the question is - what is the most desiresd pH of neutral cannabinoids?
For d8 made in heptane (must be in a non-polar solvent) you could run it trough media bros and that would pull the red out. We would then flush the media with ethanol and then re-run it up to 5x before swapping out with new media.
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I personally like mason jars for storage specifically for this reason, just vacuum the lid on then you dont have to worry about backfill
Just to clarify too
Im not saying quinone is only formed in alkaline conditions, high pH speeds up the process especially with cbd
If you take cbd and run it through magsil youll see your cbd will come out purple because the high pH of the magsil causes the cbd to convert to cbd quinone quickly in the presence of oxygen. If youre in an inert enviroment this will not happen.
Thc isnt as sensitive to alkaline conditions IMO as cbd but high pH can definitely contribute to a faster oxidation rate on distillate IMO
What OP should do is take some of his distillate and water wash it with some pH7 water and check the pH of the water after. It would be interesting to see the results on the water itself
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The jar on the right has been in the fridge for 2 or 3 days now and both of them have been completely open with their lids off for over 2 weeks now.
This Is how hard the distillate is when it’s sitting in a well air conditioned room (about 68°f)
I really do appreciate all you guys trying to help but you should know that this stuff he (my friend that pointed out the problem to me) mentioned in his in his text from 3 months ago actually all of it not just part of it turned dark and now it’s back to almost clear.
This is the stuff I gave him 3 months ago that started its life fairly clear with very light tint and then turned dark and afterwards turns almost water clear again
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No change in temperature? No change in exposure to light? No change in the kind of light he’s viewing it under?
Same amount of mass remaining (i.e. no evaporation?)
No exposure to other stuffs?
Any exposure to mechanical action? Vibration, stirring, shaking?
What are you distillation parameters? I have a few fringe theories:
1)Iron in your extract? Very few molecules of Iron Oxide could cause pretty dramatic discoloration. Maybe the temperature could affect the refractive index of oil, causing more iron-oxide color to appear. I propose this because of your initial statement about using tap-water. Perhaps not iron, but other physical contaminants that could co-distill. Even PPB could affect color.
2) @Cassin and I both proposed that it simply mixes back in due to warming. I’m still in this camp.
3)Maybe polymerized compounds? Is he microwaving the distillate? Overdoing it on the microwave(too powerful or too long) can result in the phenomenon you are seeing.
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No to any of the above questions, but the stuff that’s left out in the office is exposed to ambient light.
@Ganjineer710 I too think it’s most likely something that is contaminating the water I’m using(which would include causing a pH problem). Your question about microwaving seemed valid so I asked the guy and he said he never uses microwave on any distillate.