Extraction Technique: The Full Turps Cure

posted by geezmeister

The “Full Turps Cure:” (Placebo’s technique restated.)

Materials required:
OTC pseudoephedrine tablets
Hotplate
Fan
Pyrex evaporation dish
Funnels, cotton balls, coffee filters
Stirring rod
Non-polar solvent of choice
Mineral turps
Acetone
Alcohol of choice (methanol, ethanol, etc.)
Beakers or collection jars.

Abstract of Procedure:
Turps soak
Non-polar solvent boils until clean
Acetone boils until clean
Dry
Extract 3x with alcohol of choice
Evaporate to near dry, acetone flash
Recrystallize

Statement of Procedure:

Grind pills thoroughly. Soak for twelve hours in mineral turpentine. Alternatively soak for twelve hours in odorless mineral spirits, toluene, or xylene. Decant, discard solvent.
Transfer pill mass to suitable shallow bowl or evaporation dish.
Cover to twice its depth in non-polar solvent of choice (recommended solvent: mineral spirits). Place on heating element in a location with adequate ventilation with a fan blowing across the top of the container. Heat slowly with continuous stirring until the solvent reaches a gentle boil; adjust heat to maintain a gentle boil, with constant stirring, for five minutes. Remove from heat. Decant solvent. Use “panning” motion to separate as much solvent as possible while retaining pill mass. Alternatively, filter the solvent and pill mass through three coffee filters; retain pill mass, return to dish. Examine filtered solvent. It should be cloudy.
Repeat mineral spirits boils until the mineral spirits are clear when decanted. Test the clear, decanted mineral spirits by adding water; if anything precipitates out with the addition of water, repeat mineral spirits boil until the solvent is clean when decanted. Expect three boils to be necessary; dirtier pills or poor technique may require additional boils.
Cover the pill mass with three times its volume of dry acetone. Slowly bring to a gentle boil, with constant stirring. Boil for five minutes, allow to settle, decant. Continue with acetone boils until the decanted acetone is clean. Test for contaminants by adding water to decanted acetone and observing whether adulterants precipitate out. If so, continue acetone boils until acetone until it decants clear without adulterant precipitating with the addition of water. Expect three boils to be sufficient, depending on pill content and operator technique.
Allow pill mass to dry thoroughly.
Transfer pill mass to beaker or glass container of sufficient size to allow the addition of at least three times the pill mass’ volume of alcohol of choice. MeOH and/or denatured alcohol are recommended alcohol's. EtOH may be used if dried. Isopropyl alcohol may be used if dried. Allow pill mass to soak with agitation or stirring for twenty minutes.
Prepare a funnel by placing cotton balls in the neck of the funnel and fitting the funnel with three coffee filters. Decant alcohol from pill mass through three coffee filters and allow to drain into a clean glass container.
Return pill mass to beaker and repeat step 6, except the time for soaking should be reduced to ten minutes. Decant as before.
Soak pill mass a third time as in step 6, except decant after five minutes. (Save pill mass until final yield is determined to be satisfactory).
Place collected alcohol in evaporating dish and evaporate over very low heat, with a fan or hair dryer blowing across the surface until almost completely evaporated. Flood with dried acetone. Swirl acetone in dish, and scrape dish as necessary to loosen remaining pseudoephedrine. Decant acetone (or filter through three coffee filters.) Allow to dry.
Heat dried ISO alcohol to boiling. Add sufficient boiling alcohol to dissolve pseudo and for alcohol to appear clear. Filter through three coffee filters. If alcohol solution remains cloudy, filter through three coffee filters and Charmin plug. Rinse filters with small amount of fresh alcohol. Reduce volume of alcohol in evaporation dish at until first signs of crystal formation appear. Add just enough alcohol by drops to dissolve surface skin, add equal volume of dry acetone, cover with air tight lid or saran wrap, place in refrigerator.
Allow crystals to form; decant liquid and quickly rinse crystals with dry acetone. Add rinse acetone to remaining liquid and evaporate down to saturated alcohol, add acetone, and allow crystals to form again. Rinse these.
Combine crystals. Re-dissolve in boiling alcohol and repeat crystallization. Harvest final crystals. Photograph with digital camera. Discard, as these crystals may tempt you to do something illegal, and this board does not approve of or encourage such activities.

Notes and Comments:

The Post is not original with the poster, who makes no claim to its creation, refinement, or utility. SWIG first used the process after reading Placebo’s post concerning the turps cure. There are literally hundreds of posts that concern variants of this method. This post is presented as an extraction technique post to the Stimulants forum whose purpose is to help simplify the searches concerning such techniques, provide as much as possible a straight-forward expression of the basic technique, and provide a thread for their discussion, notes on effectiveness, warnings, and exceptions.

As with all pill extraction, the finer the pills are ground, the more likely the extraction will be complete and successful.
Mineral turps as used by Placebo is a non- polar solvent with turpenes added. Gum spirits of turpentine is not the same thing. Turpentine substitutes containing xylene and other solvents with added turpenes are considered the equivalent of Placebo’s “turps.” The poster acknowledges the contributions of numerous bees who have noted that soaks in mineral spirits, xylene or toluene also work; SWIG’s experience confirms this. Poster notes that some bees report boiling the solvent hastens the removal of the povidone. Poster does not dispute the finding.
Boiling any flammable solvent is an extremely dangerous practice. At no time should any solvent be heated oven an open flame or on any apparatus that is capable of producing a spark, and this includes defective or damaged electric hot plates. Adequate ventilation is required. This should not be done in a closed environment due to risk of explosion and/or fire and due to health concerns regarding inhalation of solvent fumes. The procedure should not be done without the constant use of a fan positioned to blow across the solvent. The fan will disburse the vapor, reduce the risk of fire and explosion, and reduce the surface temperature of the solvent. The solvent should be heated to a gentle boil, and once such a boil is achieved the temperature should be reduced to maintain the boil. If the pill mass sticks too quickly to the evaporation dish, the temperature is probably too high. A rule of thumb is that constant stirring is needed to keep the pill mass from sticking, but the stirring should not be a matter of scraping the pill mass from the pan. Some solvents can be heated to a temperature high enough to caramelize the pill mass. Note the procedure does not call for boiling the pill mass in turps. The unpleasant aroma of the turpenes is not the only reason for this. Some of the turpentine substitutes have a boiling point high enough to caramelize the pill mass. Be forewarned. The temperature at which the solvent begins to boil is sufficient for our solubility purposes. The increased solubility at higher temperatures depends on pressurization as Dwarfer will readily advise, and not on an increase in temperature or rate of boiling. Cautions regarding boiling solvents should be heeded in particular when acetone is involved as one does not wish to experience what happens when you ignite several hundred milliliters of boiling acetone.
Any solvent used should be dry. This is particularly true with acetone, which should be dried before use. Most OTC acetone contains significant amounts of water. Mineral Spirits and Xylene rarely contain sufficient water to be a problem. Toluene has more affinity for water than xylene; whether this presents a problem is outside SWIG’s personal knowledge as he has difficulty obtaining Toluene locally and has little practical experience using it for this purpose.
Testing the decanted solvent for dissolved gakks is only necessary when they appear to be clear. The poster notes that crashing the gakk with cool water in the hot solvent seems to work, and has never explored other methods aside from allowing the solvent to cool, which also allows most gakks to precipitate to some degree. The method of determining whether the solvent is still extracting trash is by no means exclusive or exhaustive.
Allowing the pill mass to dry thoroughly before extracting the pseudoephedrine is believed by many to improve yields. Poster has never verified this.
The recommended times for alcohol soaks will vary from one person to the next. Many recommend long soak times, other short soak times. The principle behind the recommendation of this poster was observed in a series of alcohol extractions of alcohol extractable OTC decongestants which recorded the yield and relative purity of the extracted pseudoephedrine, and the presence of waxes, oils or other by products which impacted the RP/I2 reaction. The notes were not retained, and were intentionally destroyed. The recommended soak times are based on SWIG’s hands-on observations that MeOH will dissolve more than pseudoephedrine from the tablets if given the opportunity either due to too little pseudo being left to dissolve or the alcohol given too much time to dissolve other substances which are not as readily soluble in the alcohol as pseudoephedrine. One hundred percent extraction of pseudoephedrine by alcohol from OTC pills is regarded by the poster as myth and misleading. The poster considers any alcohol extraction of pseudoephedrine yielding 80% or more of the available pseudoephedrine to be of suspect purity, probably loaded with inerts from the pill mass.
Many report success with extractions with heated alcohols. Heating alcohols in pills containing stearates may have adverse impact on yield and purity of the pseudoephedrine so extracted. The increase in solvency of the alcohol caused by heating also makes the gakks present in the pill mass more soluble in the alcohol. Heating of the alcohol should be considered with regard to the ingredients in the pill mass.
This technique does not list as a step placing the alcohol in a freezer to assist in removing waxes or gels. This is not to be considered a statement that the step is not of benefit in the process. SWIG’s experiences with the “full turps cure” have seldom had a wax problem. Any glycol that survives the soaks and repeated solvent boils may be dealt with by recrystallizing the extracted pseudoephedrine. If you believe a cold environment will help obtain a cleaner product, you should follow your instinct. Freezing the alcohol will not be a detriment and may provide a benefit.
Evaporation of the alcohol should be done over low heat and with a fan or hair dryer blowing across the dish. There are a number of variants for drying, from using no heat to using heatlamps under glass. You can burn the pseudo with too much heat, and the heat can get away from you very quickly. Do not walk off while the pseudo is evaporating, as this is an invitation to its destruction by heat.
Acetone flashing with dry acetone when the alcohol nears complete evaporation is a “final step” for evaporation and will help remove some impurities. See [geezmeister: "Re: Acetone Crashing" (Stimulants)] for this poster’s suggestions on the flashing technique.
Recrystallizing the pseudo ephedrine will help isolate and exclude waxes and glycols that sneak through, and will help isolate and remove various cellulose fillers that may have also been extracted with the pseudoephedrine. Dry ISO alcohol is recommended by the poster for this purpose. Some of the potential gakks are highly water soluble and the dryness of the alcohol used in this process is a great benefit.
The poster has never included a TCE wash as part of this procedure and has no personal knowledge of the benefits or detriments of such a step, or any idea whether such a wash would be beneficial or detrimental to the process.

Advantages and Disadvantages:
The near-universality of this procedure is its great advantage. If done properly it will clean most pills available OTC. Properly done, the full turps cure yields satisfactorily clean pseudoephedrine for the purposes generally discussed here. This method is a viable extraction technique for those unfamiliar or uncomfortable with A/B extraction techniques.

The process does use a volume of solvents, is dangerous to person and property, presents a serious risk of fire and explosion if not properly done, can subject the pill mass to temperature that can damage the pseudoephedrine sought to be extracted, and creates a noticeable solvent odor capable of being detected. It is rather time consuming and requires constant attention.

Known to be effective with:
most pills.
Tested by this poster on pills containing the following ingredients:

Pseudoephedrine HCl 60 mg
(See US patent 5098715)

Pseudoephedrine HCl 60 mg
may also contain:

Pseudoephedrine HCl 60 mg

Pseudoephedrine HCl 120 mg

Pseudoephedrine HCl 240 mg
Also red hots, generic and name brand.

Additional data posted by geezmeister
1) Pseudoephedrine hydrochloride is not soluble in non-polar solvents, whether or not they are hot. It also is not partiuclarly soluble in dry acetone (damp acetone is another thing altogether). It is therefore an essentially safe assumption that these solvents will not extract pseudo from the pill mass.
2) I know the cure works with red hots because SWIG did it. But he did not have the label to list the ingredients. The pills SWIG pulls from are ususally white 60's with antihistamine or the time release type. He had some of those boxes still around.
3) Minimalist approach is three alcohol soaks and take what you get. In between? Minimum of an acetone boil and a mineral spirits boil, with alcohol extraction, no recrystallization. But why? If this is worth doing, it is worth doing right. There is no sense in half doing the extraction if you are going to do an RP/I2 or hypo cook. Clean in = clean out. Trash in = trash out. The Birch reduction is more gakk tolerant. That does not mean that clean feedstock does not yield purer product. As to whether it is known what adulterants cause post-reaction problems, the answer to that question is yes. (I'm not real sure who it is that knows, but...) Povidone is a yield killer, as is polyethylene glycol. Waxes damage the precursors, can reduce the yield, can infect the final product. Cellulose fillers do nasty things for smokers and weaken the product (dilute it). Anithistamines can carry through and leave odd colors and tastes for smokers. Some adulterants are there to foil extraction, some are there for other reasons and impact the extraction. SWIG has not dealt with them all. This cure seems to catch most all of them.
Regarding the turps soak:
The point of the turps soak is to remove povidone, and it works. The notes and comments reference current wisdom that soaking the pill mass in most non-polar solvents will remove povidone. Foxy2 states a strong case for the use of odorless mineral spirits. Povidone is removed by the initial non-polar solvent soak. Polyethylene glycol is removed at the same time.
I have not taken the time this morning to reread Placebo's series of posts on this extraction technique. I do recall there was the "cure" which came to be known as the "lesser cure" and then there was the "full turps cure" which addressed the povidone problem successfully. I am not familiar with his work on steam distillation. I am aware that he was battling povidone after having done the "lesser cure," which is why the "full turps cure" was such a major innovation at the time. The terminology about the "the cure," "the lesser cure," and "the full turps cure" evolved after the posts themselves. I believe this may explain some of your questions concerning Placebo's posts.
This post merely restates the "full turps cure" in a format devised for extraction technique threads. If you check, you will find that I make no claim to its invention, perfection, or modification. I do not even advocate its use, as IMHO waterless a/b extraction techniques yield superior product with less effort. I merely restate what I consider to be the current consensus about the technique in response to a request that I do so.
"Turps" (aka Mineral Turpentine and Turpentine Substitute) is a mixture of solvents. The turpentine substitute sold by the big retailer is basically xylene with turpenes and a few other things tossed in. "Mineral turps" as described by Placebo in the original turps cure post is a substitute for gum spirits of turpentine, and is most usually a xylene based mixture with some other solvents, alcohol, acetone, and turpenes. Gum spirits of turpentine is a different solvent altogether. "Mineral Turps" as described by Placebo is not the same thing as "mineral spirits."
Current thinking is that a long soak in any suitable aromatic non-polar solvent will rid the pill mass of povidone. Xylene and Tolulene will, as will odorless mineral spirits. The Bees posting this information are credible and have no motive to post false information.
That said, be advised that the "turps cure" involves a soak in a turpentine substitute consisting of aromatic non-polar solvents and turpenes. The success of Bees who have removed of povidone without the use of turpenes indicate the turpenes are not essential to this purpose. The fact that gum spirits of turpentine fail to remove povidone tends to inidcate that turpenes themselves are not the active agent in dissovling povidone. The notes and comments section discusses the use of solvents other than "turps" for this purpose.
It is very difficult, however, to restate the "full turps cure" without discussing what the "turps" in the "cure" in fact is. This issue has been beaten to death in earlier posts on the turps cure, and need not be restated further.