Background information:

Cacti such as Trichocereus Pachanoi, Lopophora williamsi and peruvian torch are all mescaline containing plants, the alkaloids in the cacti exist as a combination
of freebase (oils) and salted forms, freebase mescaline is slightly soluble in water but more highly soluble in aromatic solvents such as xylene and toluene, the
salted forms of mescaline (not, HCL or sulfate salts) but carbonates are highly soluble in water. There is no need to worry about the latter in this Straight To Base extraction
for all the mescaline is transformed into the former at step 2.1.

Mescaline although existing in freebase and salt forms, it usually reacts slowly with the carbon dioxide in the air to form the carbonate salt.

Mescaline Carbonate Properties:

Molecular Formula: C11H17NO3
Molecular Weight: 211.26.
Properties: Crystals, mp 35-36°. bp12 180°. Moderately sol in water; sol in alcohol, chloroform, benzene. Practically insol in ether, petr ether. LD50 i.p. in rats: 370 mg/kg (Speck).
Melting point: mp 35-36°
Boiling point: bp12 180°

Water boils at 100°, way before the mescaline carbonate will turn into its gaseous state, you will not lose product through evaporation, only through lack of laboratory abilities.

This extraction is a two step process, with several individual steps. Step one, the longer one is an extraction, step two is a wash.
Extraction and washing is the same thing, as my cat's chemistry teacher's old colleague would say.

(...) extraction is pulling out what you want from all else!
Washing is pulling out all else from what you want.

A rundown of what happens is the afforementioned mescaline is completely turned into it's freebase (a basic organic compound free of a conjugate salt.)
The freebase is now more soluble in the organic layer and will be mostly miscible in it while some remains in the interface. The phases are separated and salted
with a mineral acid, this makes the mescaline soluble in the water layer, evaporation yields an impure product which needs washing.'

Note:
Never, never, never, never,
ever throw away any layer, until you are absolutely sure you'll
never need it again. Not very much of your product can be
recovered from the sink trap!

After repeating the extraction steps three or so times no more product should come off, now you can discard the plant matter.
Remember NaOH or CaOH are used as drain cleaners so don't hesitate to empty them down the drain. Use a filter to discard the plant matter.

Materials needed:

Safety Goggles
Polyethylene/latex gloves
Respirator mask.
Sodium Hydroxide
Xylene/Toluene/Non-polar solvent of your choice (not naphtas or other straight-chained hydrocarbons)
Measuring cup.
Hydrochloric/Muriatic Acid (My cat uses 33% or 21 baume)
Cactus of your choice.(My cat used peruvian torch from comprasperu.)
Coffe grinder/Magic bullet/blender etc.
Baster/pipette (the latter is preferred as it is easier to control)
One medium sized (400-500mL) mason jar, with lid. (My cat finds any washed containers works.
An HDPE 1 or 2 plastic jug with a tight steal or an airtight preserving jar works.
Table salt (iodized works as well)
Anhydrous Acetone
Funnel (preferably HDPE-1 or 2, if this isn't viable use low heats when using your xylene or toluene) Or find a funnel that is not transparent as these tends to be
PP plastics.

Ventilation is extremely encouraged for the well-being of yourself and others around you.

Extraction

1) Obtain your cactus and grind it to the finest powder possible, a magic bullet is preffered, if this isn't available, a regular coffee grinder (manual/electric)
will work. 100 grams will be a good starting point for you.

2) Weigh out 42 grams of Sodium Hydroxide and add slowly to one litre of warm water while stirring with a metal/glass rod. (A spoon will work as well but then again, be careful.
. This is a 1M solution (1mol NaOH / 1litre H2O)

This step will create a lot of heat, this is good for the purposes up ahead but again be careful, lye takes a long time to burn your skin but it will blind you
more than any strong mineral acid will.

Now add a bunch of table salt, too much is not a problem, you want to saturate the water (you'll be able to tell when the salt starts to deposit at the bottom)
NaCl solubility is 1.73 grams per litre of water, if you want to be exact. This will prevent an emulsion and will decrease the solubility of Mescaline freebase in water
and will cause migration of the alkaloids to the top layer.

2.1) While the basic water solution is hot, pour in your cactus and stir rapdily, let this sit for about five or so minutes, you will start to smell the scent of tea, although
it reminds me of the smell of kratom over chamomile tea.

2.2) After five or so minutes add your non-polar solvent of choice (both toluene and xylene cause emulsions in my experience, but this can be eliminated later.)
My cat likes to add about 120-150mls of xylene, a bit of excess is not a bad idea for basters and low-quality pipettes tend to draw the mucilage in the interphase, causing impurities later on

2.3) Seal your container, (if you have a jar with plastic tight seals make sure they don't come in contact with the NP solvent while it's hot as it will deform the seal.)
-Hold both ends and shake vigorously, the more and longer you shake the higher your yields will be.

3) Go to bed, wait about a day and half, keep checking the container for an emulsion, if there is one, submerge the container in scalding water this will cause it to separate much better.
If there is still a third "layer" in between add 10 grams of NaOH and some salt to the container, use a glass rod to stir this, this should clear it up.


4) After 36 hours or so submerge the container again in warm water, you want the least amount of freebase in the bottom layer.

4.1) Now you should have two distinct layers, one (your water layer) with all the murky cactus sludge at the bottom and a yellowish (sometimes green-tinted xylene/toluene layer.)

Pipette or baster the top layer into a mason jar, if possible use a glass baster to see whether or not you have drawn mucilage off the jar, if you have you can slowly pour back the contents of the baster
back into the jar, remember water has a higher specific gravity (higher density) than xylene, it will pour out first given you are holding the baster in a vertical manner.

Close this jar off to prevent evaporation/fumes.

5) Obtain 250ml (one cup) of distilled/filtered water and add eight drops of muriatic acid. (If you have a different concentration, say 20% you will need 16 drops.)
This information is derived from an estimated yield of 1% (i.e 1 gram per 100 grams of cacti.)

Note: 250ml should be used given your solvent layer is about 100ml, the higher the water to xylene ratio is the better your yields will be, otherwise a lot of shaking is needed. Test the water layer that's being evaporated, if it is neutral of slightly basic then the acid has been your limiting reagent, there is more mescaline in the container.

Excess acid will cause black impurities in the final stage, too little acid is better than too much for a cleaner, more easily dosable product. The solvent you use will
be reused, if a scale is available you can determine the limiting reagent (freebase vs acid) and gauge how much more acid is needed, if any at all.

pH paper should turn red after being dipped in this solution.

6) Now mix the acid water just made with the collected solvent and shake vigorously, let settle for about a minute, bubbles should form and the layers should separate.
Shake it again just to be sure all the mescaline has reacted with the acid and stick it in the freezer, depending on the amount of water used this should freeze in about
40 minutes to an hour. This again varies with temperature, etc.

7) Remove the mixture from the freezer, the bottom layer should have frozen while the top layer will remain intact, decant the np layer back into the extraction jug,
wash the ice water with a teeny-tiny little bit of lukewarm water, throw this away, don't put this back in the collection jug.

-Note: You do not need a freezer to separate the layers, a baster will work, just draw off the top layer, knowing that water has a higher specific gravity you can decant the first liquid that comes off the baster back into the freezing jar

Break up the ice with a stainless steel knife. (My cat prefers a ceramic bowl, although I've had no problem with metal pots, it's a hassle to scrape it off.)
Note: Teflon non-stick pans would be a very stupid decision to use.

Boil this off at medium heat on a stove's element, when the water is halfway or 2/3s evaporated add a half cup of water more, this will allow any excess HCL to evaporate.
You can do this step indoors just be sure you have a fan blowing the fumes out of the way, HCL will burn your nose, if you inhale please make sure you brush your teeth for the
mineral acid will dissolve and eat away your enamel.

If the acid to freebase ratio was about correct you should get a tan to dark coloured sediment deposited, scrape this off with a blade or a razor.
This is Mescaline Hydrochloride, a very impure version of it.
Note: It is safe to consume, any excess acid will not be benign to your body.

Washing: (This step is optional for the product collected above is safe to consume orally. Not intransally, or IV'd)

9) Now you have collected your impure mescaline from the bowl, add enough water so all of it dissolves. Obtain a funnel and just enough cotton so that it's not too tight
so water won't flood upwards but not too loose the cotton will fall down the stem of the funnel.

10) Now, pour the water down the cotton filter, this should clean it up from most unwanted solids, get some fresh water and pass it through the funnel so no product
stays dissolved in the cotton. Discard this cotton.

11) Evaporate this water gently, you will still smell the excess hydrochloric acid, your product should be purer now.

12) Pulverize (use a blunt object) and add anhydrous acetone (non-anhydrous acetone will not work as you will discard your product,) by placing this in a bowl you can
swirl the bowl around moving the acetone and all the gunk around, use a paper towel to absorb this.

Dry this in a dessicator bag or on a stove top element on low heat.

This tek is just a regurgitation of what is present in the web, my cat expands on some of the information a bit more than others.
Credit is due where it's due, no need to name drop as the techniques used here have been used before the creation of the internet.