"This stage rotates all the existing lesser cannabinoids and cannabinols into
THC, and all the existing THC into the most active isomer, delta-9-THC. This
step involves the use of sulfuric acid, so I shouldn't have to remind you to
wear long rubber gloves, don't inhale its fumes, DON'T TREAT IT CASUALLY
BECAUSE IT CAN EAT HOLES IN LOTS OF THINGS, INCLUDING YOU.
Dissolve the extract in 10 times its own weight in ether. SLOWLY, add one drop
of sulfuric acid for each gram of extract, stirring with a glass rod. Heat as
in the initial extraction, with the jar covered by a watchglass. Cook two
hours, stirring occasionally, and allow to cool.
Mix the solution with an equal volume of cold water and one-half its volume of
cold ether, and repeat the shaking and separation steps. Take extract and
slowly add the calcined ash from the first extraction. Stir it all in, and run
the solution through filter paper to strain the ash sediment out. Check for
any remaining acid by adding a small pinch of sodium bicarbonate (baking
soda). If the solution fizzes, keep adding bicarb very slowly until fizzing
stops.
Add fresh water and ether, shake and separate. Cook at 104F until the ether is
evaporated. Voila! You now have essence of cannabis, which can contain
anywhere from 85 to 99 percent THC"
found that at erowid......
__________________________________
and this at cannabis culture-
The potency of marijuana can be increased by about 50% simply by simmering a water slurry of the material for 2 hours. Add water as necessary to maintain the level. Cool and filter the mixture, and refrigerate the aqueous solution. Dry the leaf material at low heat. Drink the tea before smoking the marijuana. The effects are much more intense and last longer than those from the untreated leaves. The boiling water treatment isomerizes the inactive CBD, and decarboxylates THCA to THC.
Although Cannabidiol (CBD) has no psychoactivity, it does antagonize THC and produces other valuable sedative, antibiotic, and anti-epileptic effects. CBD can be isomerized to THC. If the plant is Phenotype III (containing mainly CBD in its resin), isomerization can double the yield of THC.
The CBD fraction of column chromatography can be distilled (bp 187-190° C/2 mm; pale yellow resin) to purify it. Isomerization can be accomplished with any of several solvents and acids. Alcohol and sulfuric acid isomerizes only 50-60% of CBD to THC; p-TolueneSulfonic Acid (p-TSA) in petroleum ether or other light, non-polar solvent will convert 90% of CBD to THC upon refluxing 1 hour at 130° F. (16, 17)
Reflux 3 gr CBD in 100 ml dry benzene for 2 hours with 200 mg p-TSA monohydrate until the alkaline Beam test (5% KOH in ethanol) is negative (no color). The Beam test gives a deep violet color with CBD. Separate the upper layer, wash it with 5% sodium bicarbonate, wash again with water, and strip the solvent. The remaining viscous oil should give a negative reaction to the Beam test. The crude THC can be purified by distillation (bp 169-172° C/0.03 mm), or by chromatography in 25 ml pentane on 300 gr alumina. Elute with pentane 95:5 ether to yield fraction of CBD and THC. Combine the THC fractions and distill (bp 175-178° C/1 mm).
Reflux 2 gr CBD in 35 ml cyclohexane, and slowly add a few drops of sulfuric acid. Continue to reflux until the Beam test is negative. Separate the sulfuric acid from the reaction mixture. Wash the solution twice with aqueous sodium bicarbonate, the twice again with water. Purify by chromatography, or distill (bp 165° C/0.01 mm). Any unreacted CBD can be recycled.
Another method is to reflux a mixture of 6 gr dry pyridine hydrochloride and 3 gr CBD at 125° C until the Beam test is negative. Wash the reaction mixture with water to remove the pyridine, then extract the mixture with ether. Wash the ether with water, evaporate the ether, and distill the residue i.v. to yield pure THC.
Similarly, reflux 3 gr CBD in 150 ml ethanol with 50 ml 85% phosphoric acid until the Beam test is negative. Work up the reaction mixture, and purify the THC.
Alternatively, reflux 3 gr CBD in 100 ml absolute ethanol containing 0.05% HCl for 19 hours. Extract the ether, wash the ether with water, dry, evaporate, and chromatograph on 400 gr alumina to yield
I remember seeing hexane as a superior solvent. Hexane's got to be everywhere......hobby store
