Saline / Salt color scrub SOP

Hey folks,

Looking to see if anyone has a simple to follow SOP for doing a saline scrub. A bit of backstory. We’re able to produce pretty good quality distillate and have incorporated a AC (Activated Carbon) scrub into the work flow. We normally do the AC scrub after the first SPD pass. However we noticed the material (oil and etho) turning reddit after the AC scrub. Doing some digging showed that doing a saline wash/scrub would help with the redness. But unfortunately I can’t see to find any instructions on how to actually achieve this.

Thanks in advance

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4:1 if its crude and 3:1 if its first pass.
If u have 1L of crude, use 4L of heptane.
Now get 20L ready of each:
Ph 4 water @30C with 15% salt.
Ph 7 water @30C with 15% salt.
Ph 9 water @30C with 15% salt.
Ph 7 water with 5% salt.
Ph 7 water.
Use Citric acid for ph down and and baking soda for ph up (mod edit: these were backwards…).
U want to mix ur heptane mix 1:1 with each mixture in the order i listed. (Order of first 3 doesnt matter, atleast i cant tell) You will do 4 washes of each ph before moving onto the next mixture and make sure you finish it off with 4 rinses of plain ph 7 water.
Shake/agitate the shit out of it for 2 minutes, then let it settle for 15 minutes before emptying out the water portion. I like to collect all the end portions (the part that is part water and part heptane) in a separate sep funnel, and I usually catch a couple grams that would have been dumped with the water

I really like to filter through a packed silica/T5/ Activated alumina column or even butchner after these steps.
If u can do it all under nitrogen and slight pressure, it helps a ton with the color

At the very least flush the solvent through some molecular beads like 3a but 10a works better. To capture all the mini particles of water that are suspended in the heptane mixture

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I agree - it helps with emulsions a lot too!

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Hey thank you so much for the step by step. Much appreciated.

Hey,
Quick quandry.
I’m pretty sure the pulls wouldn’t saturate.
Do you discard after each use? (I realize it’s cheap to make) or do you re-use your rinses?

No I wouldnt reuse ur rinse water.

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Noticed you said baking soda drops ph. It does not. Baking soda raises ph and vinegar lowers ph in water citric acid aswell lowers ph. just pointing out the switch up there

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Thanks for the catch, I accidently switched up and down. Citric acid is Down. Baking Soda is UP. Sorry about the confusion earlier, thanks @rushfarm

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i thought that is what happened. has anybody used vinegar to lower there ph? i used vinegar today for the saline scrub at 4ph. and it REALLY CRASHED out the soliubles fast as hell

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No, but I’m kinda intruiged

I think the acetic acid can only get down to 4 but it seems to be crashing faster than the citric acid as the ph down buffer.

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Only true if the pH is below the pka of the titratable proton on baking soda!!! Baking soda has both acid and base capabilities!!! Will for sure donate proton in strongly alkaline solutions, dropping pH

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Having trouble getting my saline solution to ph 9. Can I use anything other than baking soda ? I have a ph up but it contains potassium carbonate and potassium silicate.
Will this work?
Thanks in advance

Edited

No that was wrong for sure, baking soda up. Citric down.
Is it stopping at 8.7 when adding baking soda?

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@rushfarm
I recently used beer just for shits and giggles and it worked pretty good too seperating things out haha

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We finally got it to 9 but it took a lot of baking soda. We also had to heat it up on the stovetop. Still ended up with a bunch of baking soda at the bottom. Just trippin off how little citric acid it took and how quickly the ph changed and how much baking soda it’s taking and time. Just put 2 gallons in the pot with the leftover baking soda and 15 minutes later ph of 9. Fuck me. Warm water is all I was missing. Lol.

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Yeah 30c is perfect temp for washes. 12-16g of baking soda per gallon is all it should take…

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Do you think ph of 9 will be good
I have heard,or read, of some people going higher
We are trying to get the red out of the disty,
After First pass

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Do you still use this exact procedure or any changes? Been a year since that post!

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