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official extraction help thread

Migrated topic.
Okay this is my first time posting on here hope I did this correctly!

Once you basify your solution do you then cool down before adding hot naphtha, or does it matter, cooling solution and/or heating naphtha?
The specific heat capacity of water is much higher than that of naphtha, so adding warm naphtha to the cooled base solution would be largely pointless. Aim to do your pulls at between 40 to 60°C perhaps depending on your naphtha. It's not so big of a deal though - good results have also been reported when performing the pulls at room temperature, and higher temperatures tend to give rise to a darker coloured product.
 
For an A/B extraction of MHRB, if my heptane pulls are clear, rather than yellow, does that indicate something has gone amiss?
Not necessarily - you may well have succeeded in getting a really clean pull. Put the first pull in the freezer quick and carry on with the next ones, pronto! :D
 
Appreciate the response dreamer042!

Yes, it turned black.
100g MHRB + 600ml water + 120ml vinegar + 300g lye (kept adding because the ph wouldn't rise :|)

I did cook it for quite some time prior to adding the lye... Instapot on low heat for 8 hours...not sure if I did that wrong.

because of the nature of how pH works, there should be no measurable difference if your soup is diluted 20x, or even 50x.
Also pH probes, even $2000 ones used for precision environmental assessments, still drift over a timescale on the order of merely a minute or two, even the most sophisticated field-test sensors are expected to display a result in a few seconds, stabilize around there, and be useless soon after. usually what the software does it it monitors the signal for rapid change, then, locks it at the point it starts to change. so, what you would expect to see is, it goes from 7 to 13 rapidly, landing on 14 like a plane lands on a runway, then it will just endlessly drop at an increasing rate, or a constant one, neither of which are possible outcomes for what is, the probe being charged, because this indicates a loss of that charge in the opposite direction. in the event it swings back and fourth each oscillation is going to be shorter than the last as it zeros in.

3 things you can do:

first is titrate your solution in a diluted form, maybe 1:20, to work out how much hydroxide it takes to basify a given volume.

2: just dilute all test samples, period. 1:10 or 1:20 will easily read the same pH, provided you use distilled water tho not tap. they will take longer to hit the target but it should be evident if 7 to 11 looks like a B-line to 14

3: keep the probe in a solution maybe 1-2 on the other side of 7 as what you are reading, so for alkaline, a pH of 8 using your ph4 calibration solution, especially if it requires massive dilution. or use 1% ph7 solution (not the absolute conc, take 1% of the stuff youd use to calibrate to 7, then dilute 100x and keep probe in there between uses)

if its swinging from basic to acidic or vice versa it tends to stabilize much quicker

to hit a pH of 14, a single granule of hydroxide should work to alkalize an entire cup of water to the max. pH is logarithmic, so the difference between 7 and 13 is smaller than the difference between 13 and 14. go try this out, see just how dilute you have to make sodium hydroxide solution before 1 drop of any given solution cannot totally saturate the pH of 250ml of water. at high dilution sure, it will be slower, but youll find it difficult to tune a stable landing point below 14.

In your soup, virtually any excess of hydroxide even in the milligrams results in pH 14. overbasifying does however improve water conditions for certain types of extraction, most overshoot by an enormous degree, usually to account for a variable amount of tannins which will react with hydroxide too and consume it, being perhaps the main thing besides your acid that would be stopping the pH from hitting 14 normally.

another suggestion; try using calcium hydroxide instead of sodium hydroxide. determine an equimolar amount of calcium to neutralize the acid you used, or based on a test done on a dilute sample of what it takes to reach 14, so, how many moles of, 'anything/everything' exist, and then slowly drip in a bit of sodium hydroxide after to push things over the edge (not everything forms a mono-salt, especially if talking citrate or phosphate). any calcium excess will not dissolve into a salt, and thus the calcium oxide/hydroxide unused wont be around to cause nasty side reactions, and you only have a small excess of sodium hydroxide in solution. the catch here is that it may complicate filtration or seperation, but calcium is also gentler since it kind of has to be pulled into solution, wheras sodium, goes in and pushes other things out. look up quicklime based teks for more information on this.

And, very very last: use a needle, or something, and just prick a micro dot onto ph test strip. i use micron-sized capilary tubes i buy on ali for like $5usd/1000 tubes, that then let me do like 15 individual ph tests, or oxidizer tests, depending what im doing, per strip, i also usually snap the tube to reuse 10-15 times with fresh glass.
pH paper is better for ascertaining the point of saturation, a probe is more useful if you want to read something like pH 5-6 or 8-9 super close to neutral, especially with a dirty contaminating solution
 
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