Right
Previous guy before be was using oven cleaner to clean his distillation equipment. What do you know cleaning up the material a bit before it hits the flask and cleaning it immediately instead of letting it sit overnight and all the sudden I didn’t need anything crazy to get shit spotless again.
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Oven cleaner? Holy crap lol 
I bet that disty had some funk to it
I couldn’t even imagine
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Heptane is good for cleaning the spd as well. As long as your crude is hydrocarbon
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These? One for EtOH and one for Iso? As KOH or NaOH + EtOH or Iso + dH2O?
EtOH base bath (bath mixing procedure only; NOT a complete SOP):
Iso base bath (complete SOP):
Those base bath mixing procedures seem less than optimized considering the highly exothermic dissolution reaction of concentrated KOH solutions and the potential to boil EtOH or Iso if rushed. I have seen plastic mixing vessels bulge and weaken when someone mixes a concentrated KOH solution in them without an ice bath. So, it would probably make sense to change the base bath mixing procedure from:
EtOH base bath [~0.96 M KOH soln. [6.06% w/w KOH] pH ~13.98 @ 90% KOH]: Plastic primary vessel > KOH > EtOH > dH2O > place primary vessel in secondary vessel > wait for full dissolution > wait for solution to reach RT > lid on primary vessel > label and store, and;
Iso base bath [~0.9 M KOH soln. [~5.7% w/w KOH] pH ~13.95 @ 90% KOH]: In fume hood > place primary vessel in secondary vessel > Chilled dH2O > KOH > wait for full dissolution > wait for solution to reach RT > Iso > label and store.
To:
EtOH or Iso base bath: HDPE primary vessel in an ice water bath at a height just below the height of dH2O > pre-chilled (33-34’F) dH2O > slowly add NaOH (to limit temperature spike) while mixing with overhead mixer at low RPM until complete dissolution (adding ice to water bath needed) > mix until the solution to reaches RT (adding ice to water bath needed) > anhydrous EtOH or Iso (≥99.9% purity) while mixing with overhead mixer at low RPM > transfer to HDPE storage bottles with minimal headspace, tightly cap and seal cap with electrical tape (to reduce moisture and CO2 absorption) > label and store at ≤70’F (preferably rebottle every 30 days, max 60 days)
Other considerations:
- Replace the HPDE mixing vessel with a new one after ~10-20+ uses
- Dr. Choi doesn’t list the base salt purities, so I assume 90% for KOH and 99% for NaOH unless COA states otherwise.
- Typically, NaOH is higher purity (>99%) than KOH’s typical purity (>90%), has a shorter dissolution time, and has a weaker exothermic reaction, so it probably makes sense to use NaOH.
- Dr. Choi lists a double water rinse after soaking in base bath (tap rinse > dH2O rinse), but it would probably be better to do the standard triple dH2O rinse (with the last rinse using ddH2O). Then, test the final rinse water with a calibrated lab-grade or research-grade pH meter to confirm a complete rinse. Note that dH2O pH is 7.0, but the dissolution of CO2 creates carbonic acid, which drops dH2O to ~5.8 pH at equilibrium. If pH is below 7.0, the rinse is complete.
- The acetone solvent rinse (post-H2O rinse) should probably be a double rinse to account for dilution of the acetone by water, using ≥99.9% pure acetone (USP grade).
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So the better you extract and the more pure you make the thca the worse it will polycrystal.
For sure, on both counts!
The only chemical I didn’t link to at Duda Diesel is their EtOH. The links above for NaOH, KOH, and Iso are all for Duda Diesel 
And yeah, these strongly basic chemicals solutions aren’t anything to take lightly. Doubly so for the dH2O + base (KOH or NaOH) solution (prioer to adding EtOH or Iso) while preparing the base bath solution, which comes in about 20% w/w base. 
:
Full PPE is a must, including long sleeve shirt, shoulder length nitrile dipped gloves, pants, and safety goggles (not safety glasses) with at least an N95 face mask, but ideally a half-face respirator (an organic vapor cartridge [#60921] with an N100, R100, or P100 particle filter).
Just ask Edward Norton:
Edit:
I want to mention that anyone who wants to use this method must understand what they’re doing to avoid injury. There are many usage points I didn’t cover because I was only writing about base bath solution preparation, please read Dr. Choi’s complete SOP (it includes additional steps I didn’t cover, PPE, etc.). Also, I should point out that disposal of the base bath solution requires basicity neutralization with a dilute solution of weak acid until you reach a pH of 7-8.
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Yes thats part of it, he has a longer SOP as well with a acidic wash as part of the process as well to neutralize pH - using muriatic acid. At much lower concentrations than the base bath.
Followed by a dH2O rinse after.
Im not sure if extra strength is a better thing, you can stain/ruin your glass horribly if you dont properly wash/neutralize the very basic pH of the glass/bath, so there may be reason for that. Its not something ive studied however, but NaOH is also much cheaper so if it just requires extra washes than definately sounds like the move.
Not sure what the goal of the acetone is at the end tho tbh, can you explain what that does for the process?
Another thing to note is that your grease for joints will NOT dissolve in the mixture you must clean off so before “bathing” the glass.
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Definately a good option if you got the time/energy for it, id often work stupid long days and ache for the batch to finish so i can shut it all of and just dip. I had a 22l and body took a long time so with the extra head it didnt really take any distillation time out the day to do so.
Cyclo@cyclopath…replying to your post because you will understand the irony….
Washing cannabinoid contaminated utensils with “”basic water””
Yes!
4200 Butane Group: do you understand what you are doing…?
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Not usually, but that’s what makes it fun.
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I hope no one is making a base bath in a metal pot… saturated KOH or NaOH in iso or EtOH will dissolve glass and turn metals into explosive metal hydrides.
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Basically…not gonna lye
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Exactly why i didnt post it but someone felt the need to let the less educated help them kill themselves. and a lot of likers to support so
That persons corrections also were just reiterations from part of the full sop of the process from the same person DR Choi…
now that im realizing so i think they just used the keywords to find the process and post it themselves. You said we should edit dr choi’s to :
when it says here in is SOP “The base bath should be placed in a secondary container constructed of material such as HDPE Nalgene
and capable of containing the full bath volume in case the primary container fails. Do not store Base Bath
solutions in metal containers.”
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The olives are killing me.
If only I had pure water …
Now if NASA wanted clean and sterile items to go to Mars…what would they do?
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You edits/revisions of dr. chois base bath are reiterating the same words he used in his full SOP. A Ice bath is most def not necessary i drop 100 grams at a time in it and have never gotten close to boiling point. While it can be useful i really dont see the neccesity if you just do so slowly like most people do for any reaction. could it help u speed up the mixing with less risk yes but thats not really something that needs to be streamlined so slowly dissolving the KOH shouldnt be problematic.
@Ralf Would also like to hear the reasoning of why you think another stronger acid would be better for the process besides “its stronger.” Im all ears(eyes) if theres logic behind it but if strength is your goal theres plenty enough with KOH to get the job done(and less risks to the operators/people doing said cleaning.)
I had a chemists advise me of this one with 20+ years in the field that referred me to dr choi’s SOP im not the educated one who discovered this but was taught of it by people way more qualified than i and most of us, if they decided a more expensive acid was needed in a cleaning process there may be some reasoning to that. I dont know indefinitely but unless you have a PHD and decades of experience like them or some study/link to further prove your point im going to have to stick to their SOP’s
Also if your plastics are bulging/deforming during said process you likely didnt look up KOH/NAoHs effects on certain plastics. Some plastics have an A rating(can withstand the basic conditions for up to 6 months if i remember correctly) - a $20 tote from walmart with held the contents of base baths for 4+ months at a time before i dumped it due to it losing its efficency. some others will dissolve within the day. It goes back to the same thing as PVC/butane. and why we exclusively use high quality stianless/glass to process with butane to avoid such. And if you did search so and still resulted in that occuring you are most definitely mixing in to much at a time.
Using a dilute acid rinse as a neutralization makes sense. I assume it’s intended reduce glassware degradation. Care to share that SOP? The complete SOP from Dr. Choi in the link I shared doesn’t include an acid rinse, only a double water rinse.
The goal with NaOH isn’t to increase the base bath’s alkali concentration (strength). It’s to use an alkali of greater purity, which also has other positive attributes, including weaker exothermic reaction, less cost, and faster dissolution. The molar concentration of the alkali in the base bath would not change, where Dr. Choi’s SOPs call for ~1 M of KOH. However, when accounting for the typical purity of KOH (90%), the molarity becomes ~0.9 to ~0.96 M, depending upon the SOP used (see my other post for the two SOPs). I didn’t provide information on the NaOH concentration to replace KOH, only that NaOH is probably a better choice. I assumed that if someone followed Dr. Choi’s SOPs, they could calculate the required mass of NaOH per volume to achieve the same molarity as KOH (after accounting for purity). The difference in solution pH between KOH and NaOH at equal molarity would be minor.
An acetone rinse after a water rinse is common when cleaning lab glassware because it’s water soluble and highly polar, so it readily dissolves most organic compounds. The water rinse washes off the inorganic ions from the alkali hydroxides (e.g., K, Na, S, Cl, Fe, Ni, CO3, etc.). Then, the acetone rinse washes off residual organic material left after the base bath and water rinse.
Dr. Choi’s SOP allows the glassware to be oven dried 15-minutes after the acetone rinse and subsequent air drying.
Good idea to point out that the required glassware prewash before the base bath. Per Dr. Choi’s completed SOP (I would add that post detergent washing, a triple dH2O rinse would be ideal):
Pre-washing the soiled glassware
- All soiled glassware should be prewashed with appropriate solvent to get the glassware as clean as possible. Collect the solvent used to wash the glassware in a container and manage it as hazardous waste.
- Wash the glassware with detergent and then rinse with distilled water
I’m not sure to whom you are directing that post. But, if it’s to me, regarding my edit to this post, where I wrote, “Make sure you understand what you’re doing before using this method,” the “you” I was referring to wasn’t @cyclopath. The “you” referred to anyone reading who may not be familiar with this method (or working with strong alkalis). 
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Nice! I had no idea of so and its not something i was to interested in delving into so thanks very much for describing/ so.
It was directed to you tbh as it wouldve been to anyone else that publicly posted it as i really do think some people still wont realize the risks after reading so and may harm themselves instead of just doing normal glass cleaning even if it dried on and was a painful process.
I see you joined this site just a few months back so in all transparency verified consultants here have poured Acetonitrile from HPLC into water bottles confused it drank it… many other sketchy things have occured from people not following basic safety procedures if you delve deep enough into this site. More than appreciate the spoonful of information but yea thats my reasoning of not sharing anything to caustic/acidic or anything generally thatll put you in the ER if your lucky.
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