.
Solvents: FAQ
"Most of the substances discussed in this FAQ are toxic to one degree
or another. Usually, after sufficient evaporation/separation/etc.,
such small quantities remain, that there is not a great risk of
poisoning, but you still need to watch out for contaminants. Many of
these substances contain contaminants of unknown toxicity. DO NOT
ingest unless you know what you are doing! You have been warned!
Also, it is not a good idea to breath the fumes from most of these
substances. You could get poisoned that way too. When evaporating
or boiling off solvents, make sure there is adequate ventilation.
Most of these solvents are flammable (or explosive). When working
with flamable solvents, avoid sparks (e.g. from electrical switches)
and open flames (e.g. from gas stoves). Using a hot plate with an
extension cord to get it away from the house is a good idea. Good
ventilation is the key to preventing both poisoning by inhalation,
and explosions resulting from the build-up of flamable fumes.
ALWAYS read the label of the products before you purchase them to
make sure they contain what you are looking for, and are not mixed
with a lot of other unwanted things. (See section on PURITY)
P.S. This information is incomplete, Never assume that something is
safe just because the information is not there!
P.P.S. Only you are responsible for your own actions!!
P.P.P.S. Use your head, damn it!!!
---------------- Answers to Frequently Asked Questions ----------------
1) What is petroleum ether?
A: Petroleum ether refers generically to the lower boiling fractions
of petroleum. Analytical grades may be quite pure, containing
only hexane and/or pentane, and having a boiling point no higher
than 69 degrees centigrade. The lower boiling fractions are most
useful when the solvent is to be evaporated or boiled off. The
petroleum ethers most often mentioned on the 'net usually consist
of somewhat higher boiling fractions of petroleum (e.g. 100 to
175 degrees centigrade). These are more useful when the solvent
is to be separated and discarded (e.g. when removing oil soluble
contaminants from water soluble extracts).
2) Are ether and petroleum ether the same?
A: No! Petroleum ether is a petroleum product. "Real" ether is
more commonly known as diethyl ether or ethyl ether. Its chemical
formula is C2H5-O-C2H5, and it is not a petroleum product.
Diethy ether is the "ether" that was traditionally used as an
anesthetic the early 1900's. Petroleum ether is sometimes
referred to as "ether" because its solvent properties are similar
to that of diethyl ether (i.e. it dissolves similar types of
substances and has a low boiling point). Often (but not always),
petroleum ether and diethyl ether can be used interchangeably.
It is usually easier for the layman to obtain petroleum ether.
3) Where can I get petroleum ether?
A: Chemical supply houses usually can provide petroleum ether. Ask
for it by boiling fraction or specific component (e.g. hexane,
pentane, etc.). It is best to have a reasonable knowledge of
chemistry when purchasing chemicals or solvents from professional
establishments. Many substances are controlled to some extent.
Often they will ask you to show identification, and sign a
statement explaining what your intended use is. This information
can be provided to government agencies such as the DEA. Since
most laymen would have a difficult time bluffing their way in a
chem supply shop, they probably would be tempted to use an
industrial grade which may be more easily obtained from local
retailers. These may take the forms of mineral spirits,
petroleum spirits, naptha, automobile starter fluid, etc. See
the SOLVENTS section below for more information on these products
and where to obtain them.
4) Where can I get solvent ?
A: Most solvents can be obtained from chemical supply houses. Just
keep in mind the precautions mentioned in #3 above. Many solvents
may be obtained from local retail establishments in industrial
grades either semi-pure or mixed with other (possibly useful)
solvents. For over-the-counter sources, see the SOLVENTS section
below.
5) What are polar and non-polar solvents?
A: The easy answer: Polar solvents dissolve substances that are
water soluble, but do not dissolve oily substances. Non-Polar
solvents dissolve oily substances, but do not dissolve water
soluble substances. Moderately polar solvents have a tendency to
dissolve both types of substances. Petroleum distillates are
non-polar, alcohols are moderately polar, and water is polar.
The better (but not necessarily more helpful) answer: Polarity
is a somewhat vague notion which gives a general idea of what
will dissolve what. The chemistry-extracting file at hyperreal
states the following:
Polarity and solubility is a nebulous concept. If you actually
look at what is dissolved by what, you can only find vague
general principles, and plenty of exceptions. Some authors
have tried to make 3 and 4 dimensional polarity or solubility
graphs, and put various solvents in various points as having
a combination of different types of solvent power.
See the SOLVENTS section below for more information on the polarity
of specific solvents.
6) What is the advantage of using a polar (or non-polar) solvent?
A: The advantage is that you are able to dissolve what you are
after, leaving behind the things you don't want. (e.g. petroleum
ether will dissolve cannabinoids but leave behind chlorophyll and
sugars. Alcohols and acetone will dissolve cannabinoids,
chlorophyll and sugars.)
7) What type of solvent should I use for extracting substance ?
A: Don't ask me. This FAQ was never intended to be a compilation of
recipes. Look at the various extraction techniques which have
been posted on the 'net or look in the chemistry-extracting file
at hyperreal.com. (hint: oily substances dissolve in non-polar
solvents, most other useful substances will dissolve in water.)
What is an acid-base extraction?
A: This is a technique in which alkaloids are extracted by taking
advantage of common solubility properties of most alkaloids. In
general, alkaloids are soluble in an acidic water solution, and
become insoluble when the solution is made basic. The solubility
rules for alkaloids are reversed for non-polar organic solvents.
The basic form (precipitate) is soluble in non-polar solvents,
and the acidic form is insoluble in non-polar solvents. Most
other materials in plants do not have these same solubility
properties. This allows for the isolation of alkaloids from most
of the other unwanted junk. For more information on specific
extractions, see the various extraction techniques on the 'net or
look at the chemistry-extracting file at hyperreal.com.
9) Why does my extracted material still smell like solvent?
A: Your extract may still smell like solvent because it still has
some solvent left in it or because some of the aromatic
components of the solvent are overstaying their welcome. Some
solvents have a high boiling point which makes it difficult to
separate it from your extract by boiling it off. Even if most of
the solvent solution boils off at a lower temperature, there may
have been a portion of it that has a higher boiling point. One
way to reduce the amount of excess solvent is to heat up the
extract even more. Be careful because higher heat may destroy
some extracts. Another way to lessen the smell is to to let the
excess solvent evaporate on its own by leaving your extract
exposed to the air for an extended period of time (anywhere from
overnight to several days). The down side of this is that the
longer your extract is exposed to air, the more it can be
destroyed by oxidation. Warmer temperatures encourage both
evaporation and oxidation while cooler temperatures do the
opposite. Room temperature is probably ok for most purposes. It
may well be next to impossible to get all of the residue out,
however. Picking a good solvent from the start can help you
avoid these problems to a large extent.
10) How dangerous are over-the-counter solvents?
A: It is always best to acquire reagent grade solvents, but since
this IS an over-the-counter solvents FAQ . . .
Some solvents are very dangerous by themselves while others are
almost harmless. Some contaminants in industrial grade solvents
could be quite dangerous (poisonous, carcinogenic, flammable,
etc.), while others are not. Most contaminants are not highly
toxic, and the government imposes some regulations on
manufacturers to prevent highly hazardous contaminants from being
distributed, so one could assume that the risks posed by
contaminants is fairly low. However, if you choose to use an
industrial grade, you always run some risk. Research and common
sense can help reduce this risk. See the section on PURITY below
for a more lengthy discussion on this topic. See the SOLVENTS
section below for information on the hazards of specific
solvents. See the OTHER SUBSTANCES section below for information
on the hazards of other miscellaneous substances.
------------------- REFERENCE & GENERAL INFORMATION -------------------
TERMS: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
"bp" = boiling point (or boiling fraction in some cases)
note: boiling points are slightly lower at high altitudes
"C" = degrees centigrade
"dens" = density (in grams per ml unless otherwise specified)
"dis:" = what it dissolves
"F" = degrees Fahrenheit
"LD50" = (lethal dose 50%) dosage at which 50% of test subjects
(rats, dogs, etc.) died.
"mis" = miscible with
"mp" = melting point
"otc:" = (over-the-counter) where to find it, etc.
"pol:" = polarity ( > = more polar than, < = less polar than )
"prop:" = physical properties
"sol:" = what it is soluble in
"tox:" = data on toxicity. if not listed, DON'T assume it is safe!
"uses:" = common uses. this is nice to know when you are asking a
store clerk to help you find it.
SOLVENTS: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ACETONE (dimethyl ketone, ketone propanone, propanone)
prop: mp -94.6 C, bp 56.48 C, dens 0.80
dis: water solubles, oils; mis: water, alcohols, chloroform, oils
pol: polar?/moderately polar?
tox: oral LD50 (rat) 9750 mg/kg
otc: hardware stores (acetone)
uses: thinning fiberglass resins, dissolving 2 part epoxies,
cleaning brushes and tools used with resins or epoxies,
cleaning greasy stuff
otc: some drug stores (pure, small quantities, expensive)
uses: dissolving fats, waxes, etc.
caution: flamable, reacts with some solvents
note: acetone is also used in fingernail polish remover, but
it is mixed with water, fragrance, etc.
note: may react with some alkaloids, may extract more organic
compounds than is desirable
ALCOHOL see ethyl alcohol, methyl alcohol, isopropyl alcohol
BENZENE (C6H6, benzol, phenyl hydride, coal naptha)
(included for comparison and cautions)
prop: mp 5.51 C, bp 80.1 C, dens 0.8794
dis: oils; mis: alcohols, chloroform, ether, acetone
sol: slightly soluble in water (1 part per 1403 parts H2O)
pol: non-polar
tox: 3000 ppm vapor considered high concentration, toxic via
inhalation or skin absorption as well as oral ingestion,
prolonged inhalation of low concentrations also toxic
otc: none known (you wouldn't want it anyway)
note: do not confuse with benzine which is a petroleum distillate
caution: a recognized leukemogen (causes leukemia)!
caution: highly flamable
caution: can react vigorously with oxidizing materials
BUTANE (C4H10, n-butane, methylethyl methane, butyl hydride)
prop: bp -0.5 C
dis: oils
pol: non-polar
sol: ether, alcohol, water
otc: anywhere (butane cigarette lighters)
uses: lighter fuel, butane torches, curling irons (yes, really)
caution: extremely flamable
note: if you use this, you will have to work with sub-freezing
temperatures or at least higher pressures like a small jar
with a tight lid (higher pressures tend to raise boiling
points thus improving solvent capabilities). the advantage
is that you could boil it off at room temperature!
CHLOROFORM (CHCL3, trichloromethane)
(included for comparison and cautions)
prop: mp -63.5 C, bp 62.26 C, dens 1.498
dis: oils, fats, rubber, alkaloids, waxes, resins
sol: 1mL in 200mL water; mis: alcohols, ether, petroleum ether
pol: non-polar
tox: oral LD50 (rat) 800 mg/kg, prolonged inhalation can cause
unconsciousness and poisoning (or even death)
otc: none known
note: non-flamable
caution: reacts violently with acetone + base, methyl alcohol +
sodium hydroxide or potassium hydroxide
DICHLOROMETHANE see methylene chloride
DIESEL FUEL (fuel oil #2)
composed of heavier hydrocarbons than gasoline
prop: bp higher than gasoline
dis: oils
pol: non-polar
tox: recognized carcinogen, see also petroleum distillates
DECANE (CH3(CH2)8CH3)
a minor component of kerosene, may be a minor component of gasoline
prop: mp aprox -29 C, bp aprox 174 C
dis: oils
pol: non-polar
tox: see petroleum distillates
otc: see kerosene, gasoline
caution: flamable
DIETHYL ETHER (C2H5-O-C2H5, ether, ethyl ether, anesthesia ether,
ethyl oxide)
prop: bp 35 C
dis: oils, etc.
pol: moderately polar ( < water, alcohols; > petroleum
distillates and toluene )
tox: moderate oral toxicity, low inhalation toxicity, oral LD50
(rat) 1700 mg/kg, oral LD50 (human) 420 mg/kg
otc: found in automobile starter fluid
caution: very flamable, can form explosive peroxides with
prolonged exposure to air
note: this is the ether that was used extensively as an
anesthetic a few years back
ETHANOL see ethyl alcohol
ETHYL ALCOHOL (ethanol, methyl corbinol, spirit of wine, grain
alcohol)
prop: bp 78.32 C, dens 0.79
dis: water solubles, oils; mis water
pol: polar? / moderately polar? ( < water; > isopropanol )
tox: oral LD50 (rat) 21,000 mg/kg
otc: liquor store (Everclear, 95%)
uses: party, party, party!
caution: flamable, could get you drunk
note: there have been reports of people using denatured alcohol as
a solvent. this may be ok if it is denatured only with
something that will be eliminated when the solvent is boiled
off (e.g. with methyl alcohol). if you don't think you can
eliminate the denaturant, then don't use denatured alcohol!
FUEL OIL (fuel oil #1 through fuel oil #6)
increasingly viscous petroleum distillates, generally with increasing
boiling fractions.
dis: oils
pol: non-polar
tox: see petroleum distillates
caution: flamable
note: fuel oil #1 is kerosene, fuel oil #2 is diesel oil
note: there are not many applications that could benefit from
using fuel oils as solvents
GASOLINE (petrol, gas, white gas)
composed of octanes, some heavier hydrocarbons (nonanes, etc.),
and some lighter hydrocarbons (heptanes, etc.)
prop: bp aprox 35-180 C (depending on what it contains)
dis: oils
pol: non-polar
tox: see petroleum distillates
otc: gas stations
uses: automobile, etc. fuel
caution: very flamable
note: gasoline for automobiles contains additives, better to use
white gas.
KEROSENE (fuel oil #1, ultrasene)
composed mostly of heavier hydrocarbons than gasoline (10 to 16 carbon
atoms per chain)
prop: bp 175-325
dis: oils
pol: non-polar
tox: oral LD50 (rat, rabbit) 28,000 mg/kg, oral toxicity is low,
see also petroleum distillates
otc: fuel distributors, hardware stores
caution: flamable
uses: stoves, heaters, lamps
note: ultrasene is deodorized kerosene
HEPTANE (C7H16)
a component of starter fluid, gasoline, and some petroleum ethers
prop: bp aprox 98 C
dis: oils
pol: non-polar
tox: see petroleum distillates
otc: found in starting fluid and some napthas
caution: highly flamable
HEXANE (C6H14)
a component of starter fluid, and some petroleum ethers
prop: bp aprox 69 C
dis: oils
pol: non-polar
tox: see petroleum distillates
otc: found in automobile starting fluid and some napthas
caution: highly flamable
ISOPROPANOL se isopropyl alcohol
ISOPROPYL ALCOHOL (dimethyl alcohol, sec-propyl alcohol, isopropanol)
prop: mp -89 C, bp 80.3 C, dens 0.79
dis: water solubles, oils; mis water
pol: polar? (hydrogen bonded?), ( < ethanol; >> diethyl ether )
tox: oral LD50 (rat) 5,840 mg/kg
otc: automotive stores (fuel dryer, 99.9%)
caution: flamable
note: rubbing alcohol is usually only 70% alcohol, and 30% water
METHANOL see methyl alcohol
METHYL ALCOHOL (methanol, wood alcohol)
prop: bp 64.8 C, dens 0.79
dis: water solubles, oils; mis water
pol: moderately polar? (hydrogen bonded), ( < water, > diethyl
ether )
tox: oral LD50 (rat) 13,000 mg/kg, eliminates slowly and can
build up with repeated exposure/ingestion. toxic metabolites
include formaldehyde and formic acid. damages optic nerve.
otc: automotive stores
uses: fuel dryer
otc: hardware and paint stores
uses: shellac thinner, alcohol stove fuel
caution: flamable
note: often mixed with paint removers or varnish removers
note: good at penetrating cell walls and membranes
METHYLENE CHLORIDE (CH2Cl2, dichloromethane)
prop: bp 39.8
dis: oils
pol: non-polar
tox: oral LD50 (rat) 2136 mg/kg, VERY dangerous to eyes,
produces highly toxic fumes when heated to decomposition
(e.g. by open flames, etc.), may be carcinogenic in rats
otc: paint and hardware stores (mixed with methyl alcohol, etc.)
uses: paint and varnish remover
note: fire hazard is low (by itself)
MINERAL SPIRITS see petroleum spirits
NAPTHA (see below for types)
dis: oils
pol: non-polar
tox: see petroleum distillates
otc: hardware and paint stores
uses: paint thinner, some lighter fluids, some spot removers
note: boiling fractions are similar to gasoline
NAPTHA (coal tar, naptha solvent)
prop: bp 149-216 C, dens 0.86-0.89
tox: see petroleum distillates
caution: flamable
NAPTHA, V.M. & P. (benzine, 76 degree naptha)
prop: bp 100-140 C, dens 0.67-0.80, flash point 20 F.
tox: see petroleum distillates
note: do not confuse with benzene
caution: flamable, autoignite 450 F
NAPTHA, V.M. & P., 50 degree flash
prop: bp 115-143 C, flash point 50 F
tox: see petroleum distillates
caution: flamable
NAPTHA, V.M. & P., high flash
prop: bp 138-165 C, flash point 50 F
tox: see petroleum distillates
caution: flamable
NONANE (C9H20, n-nonane)
a component of gasoline, a component of some napthas
prop: mp aprox -54 C, bp aprox 151 C
dis: oils
pol: non-polar
tox: see petroleum distillates
otc: see naptha, white gas, gasoline
caution: flamable
OCTANE (C8H1
a major component of gasoline
prop: bp aprox 126 C
dis: oils
pol: non-polar
tox: see petroleum distillates
otc: hardware and paint stores (some napthas)
otc: sporting goods stores (white gas)
caution: highly flamable
PAINT THINNER see petroleum spirits, turpentine
PAINT and VARNISH REMOVER
usually composed of methylene chloride and methyl alcohol. may also
contain toluene and other solvents. see individual components for
more information
PENTANE (C5H12, n-pentane)
a component of some light petroleum ethers
prop: bp aprox 36 C
dis: oils
pol: non-polar
tox: see petroleum distillates
otc: see petroleum spirits
caution: highly flamable
PETROLEUM DISTILLATES (gasoline, naptha, petroleum ether, mineral
spirits, petroleum spirits, fuel oils, xylene, etc.)
dis: oils
pol: non-polar
tox: generally low to moderate toxicity, laboratory experiments
show a slight carcinogenic potential for most petroleum
distillates. higher boiling fractions may be more
carcinogenic.
caution: flamable to highly flamable
note: petroleum distillates do not dissolve most water-solubles
note: petroleum distillates include everything from pentane to
heavy tars
PETROLEUM ETHER see petroleum spirits, naptha, starter fluid
note: generally (but not always) refers to the lower boiling
fractions of petroleum distillates
PETROLEUM SPIRITS (petroleum benzine, petroleum naptha, light
ligroin, petroleum ether, mineral spirits)
prop: bp 35-180 C, dens .64-.66
dis: oils
pol: non-polar
tox: see petroleum distillates
otc: hardware and paint stores
uses: paint thinner
caution: flamable
note: "petroleum spirits" often refers to the lower boiling
fractions of petroleum distillates. However, one "odorless
paint thinner" claiming 100% mineral spirits had a boiling
point of 175 C.
note: do not confuse with benzene
STARTER FLUID
composed of hexane, diethyl ether, and heptane. see individual
components for more information.
otc: automotive stores
uses: starting stubborn automobiles on cold days
caution: very flamable
note: some starter fluids may contain heavier lubricants
alpha-TRICHLOROETHANE (CH3CCl3, 1,1,1-trichloroethane, methyl
chloroform)
prop: bp 74.1 C, dens 1.3492
dis: oils, etc.?
pol: non-polar?/moderately polar? (insoluble in water)
tox: oral LD50 (dog) 750 mg/kg, avoid fumes
otc: super markets, hardware stores, etc.
uses: spot remover (brand name: "Energine"), industrial uses
include cleaning of metal parts and metal molds
caution: can react violently with acetone
note: non-flamable!
TETRAHYDROFURAN (OCH2CH2CH2CH2, diethylene oxide, cyclotetramethylene
oxide-1,4-epoxy butane)
(included for comparison and cautions)
dis: oils, etc.; mis: water, alcohols, ethers, hydrocarbons
pol: moderately polar
otc: none known
note: peroxides may be removed by treating with strong ferrous
sulfate solution made slightly acidic with sodium bisulfate
caution: same as diethyl ether (slightly more dangerous)
TOLUENE (C6H5CH3, methylbenzene, phenylmethane, toluol)
prop: mp -95 C to -94.5 C, bp 110.4 C
dis: oils
pol: non-polar
tox: oral LD50 (rat) 5000 mg/kg, oral toxicity is moderate,
inhalation of 100 ppm can cause psychotropic effects, 200 ppm
can produce CNS effects
otc: paint and hardware stores (mixed with methyl alcohol, etc.)
uses: furniture refinisher, liquid sandpaper, paint remover
note: low fire hazard (by itself)
TURPENTINE (spirit of turpentine, turpentine gum, turpentine oil)
prop: bp 154-170 C
dis: oils ?, etc.?
pol: non-polar? (insoluble in water)
sol: alcohols, chloroform, ether, glacial acetic acid
tox: aspiration causes pheumonitis, oral ingestion causes damage
to GI tract and kidneys, inhalation toxicity is high
otc: paint and hardware stores
uses: thinning varnish, paint, & enamel; cleaning brushes
caution: moderately flamable
WATER (H2O)
prop: mp 0 C (32 F), bp 100 C (212 F), dens .99999 @ 4 C
dis: anything that is water soluble
pol: polar
tox: non-toxic unless contaminated with a toxic substance
otc: your kitchen sink (contains chlorine, etc.)
otc: grocery store (distilled water or purified water)
uses: drinking, washing, etc.
note: distilled water is better for most things (and it's cheap).
water is ofter used with petroleum ether to separate water-
solubles from non-water-solubles. i.e. combine and shake
vigorously until your arm falls off, then separate.
WHITE GAS (petrol, gasoline)
prop: see gasoline
dis:, pol:, and tox: see petroleum distillates
otc: sporting goods stores
uses: fuel for camp stoves and camp heaters
caution: flamable
XYLENE (C6H4(CH3)2)
prop: (m-xylene) mp -47.9 C, bp 139 C
(o-xylene) bp 144.4 C
(p-xylene) bp 138.3 C
dis: oils
pol: non-polar
tox: oral LD50 (rat) 5000 mg/kg, see also petroleum distillates
otc: super markets, hardware stores
uses: some cleaners (e.g. for dissolving chewing gum,
brand name: "Goof-off"), some lighter fluids
caution: flamable
OTHER SUBSTANCES: . . . . . . . . . . . . . . . . . . . . . . . . . .
ACETIC ACID (CH3COOH, vinegar acid, methane carboxylic acid, ethanoic
acid)
prop: mp 16.7 C, bp 118.1 C
sol: water
tox: oral LD50 (rat) 3310 mg/kg
otc: grocery stores (vinegar)
uses: cooking, cleaning
caution: dangerous in contact with: chromic acid, sodium peroxide,
nitric acid, potassium hydroxide, sodium hydroxide, xylene,
oleum. decomposition (at high temp.) evolves toxic fumes
note: normal vinegar is 5% acetic acid, vinegar concentrate is 18%
acetic acid
note: can be used for extracting some alkaloids from plant material
AMMONIA see AMMONIUM HYDROXIDE
AMMONIUM HYDROXIDE (NH4OH, ammonia, aqua ammonium, water of ammonia,
ammonium hydrate)
prop: mp -77 C
sol: water
tox: oral LD50 (rat) 350 mg/kg, oral LDlo (human) 43 mg/kg,
inhale LClo (human) 5000 ppm
otc: grocery & hardware stores
uses: household cleaning ammonia
note: ammonia is a gas at room temperature. it is sold otc
dissolved in water (much as is done with hydrochloric acid).
note: a weak base. can be used to precipitate some alkaloids
from slightly acidic solutions.
CANNABIDIOL (CBD)
found in marijuana, organicly converted to THC, can be isomerized
into THC by refluxing with dilute acid
prop: mp 66-67 C, bp 187-190 C @ 2mm Hg
sol: acetone, petroleum distillates, alcohols, etc.
note: this is an oily substance, not water soluble
CANNABINOL (CBN)
found in marijuana, a degradation product of THC
prop: mp 76-77 C, bp 185 C @ .05mm Hg
sol: acetone, petroleum distillates, alcohols, aqueous alkaline
note: this is an oily substance, not water soluble
EPHEDRINE HYDROCHLORIDE (C6H5CHOHCH(CH3)NHCH3 HCL, a[1-(methylamino)
ethyl]benzyl alcohol hydrochloride)
prop: mp 187-188 C
sol: water (1gm/4ml), (insoluble in diethyl ether)
tox: oral LD50 (mouse) 400 mg/kg
otc: truck stops (Mini Thins, MaxAlert, etc.)
uses: bronchiodialator (for asthma)
caution: decomposes into toxic fumes at higher temperatures
note: pure ephedrine is no longer available otc in the U.S. current
otc varieties usually have guiafenesin
note: slightly stronger that ephedrine sulfate
note: pure ephedrine can be converted into methcathinone
note: now a controlled substance in the US
EPHEDRINE SULFATE ((C6H5CHOHCH(CH3)NHCH3)2 H2SO4, 1-phenyl-2-
(methylamino)propanol sulfite)
prop: mp 247 C
sol: water (1gm/20ml), alcohol (1gm/0.2ml)
tox: oral LD50 (rat) 600 mg/kg
otc: same as for ephedrine hydrochloride?
caution: decomposes into toxic fumes at higher temperatures
note: slightly weaker than ephedrine HCl
note: pure ephedrine can be converted into methcathinone
note: now a controlled substance in the US
HYDROCHLORIC ACID (HCl, muriatic acid, chlorohydric acid, hydrogen
chloride)
prop: mp -114.3 C, bp -84.8 C, dens 1.639 g/liter gas @ 0 C
tox: oral LD50 (rabbit) 900 mg/kg
otc: hardware stores (muriatic acid)
uses: cleaning calcium or lime deposits from cement, brick,
swimming pools, and ceramic tile.
caution: caustic
note: useful in isomerizing CBD to THC. useful in extracting
some alkaloids from plant material. HCl is found naturally in
low concentrations in the digestive juices of your stomach.
LYE see SODIUM HYDROXIDE
PARAQUAT
an herbicide used by Latin-American drug enforcers to kill marijuana
crops in bulk
tox: oral LD50 (rat) 57 mg/kg, dermal LD50 (rat) 80 mg/kg, can
cause severe damage to lungs (nasty stuff!)
note: avoid all marijuana that looks like it has any dye on it.
unfortunately, not all paraquat is used with dye.
TETRAHYDROCANNABINOL (THC)
found in marijuana, the psychoactive stuff
prop: bp 200 C @ 0.02mm Hg (other cannabinoids may have bp's
lower than 185 C)
sol: polar solvents, acetone, alcohols, etc.
note: this is an oily substance, not water soluble
SODIUM HYDROXIDE (NaOH, caustic soda, sodium hydrate, lye, white caustic)
prop: mp 318.4 C, bp 1390 C, dens 2.120
tox: oral LDlo (rabbit) 500 mg/kg
otc: hardware stores, etc. (Red Devil Lye, etc.)
uses: unclogging drains
caution: highly corrosive to body tissue
caution: can react violently with acetic acid or tetrahydrofuran
note: useful in precipitating some alkaloids from acid solutions
SODIUM SULFATE (Na2SO4)
by product of isomerization of CBD to THC when sulfuric acid is
neutralized with baking soda
sol: water
note: insoluble in alcohol
note: can be removed by dissolving resin in petroleum ether
and shaking with water
SULFURIC ACID (H2SO4, oil of vitriol, dipping acid)
prop: mp 10.49 C, bp 330 C, dens 1.83
tox: oral LD50 (rat) 2,140 mg/kg
otc: plumming supply stores (plummers' sulfuric acid)
uses: unclogging drains
otc: automotive supply stores (battery acid)
caution: battery acid may have lead in it
caution: caustic, use care when mixing with water as it heats
rapidly when dissolved and causes spattering (add slowly to
water drop by drop)
note: useful in isomerizing CBD to THC
VINEGAR see acetic acid
SUBSTITUTIONS: . . . . . . . . . . . . . . . . . . . . . . . . . . .
It is not always easy to come up with the exact solvent discussed in
any particular recipe. Consequently, it may be advantageous to
consider substituting an over-the-counter solvent for a hard-to-get
one. This can often be done successfully if you keep a few things in
mind. The main thing to look for is what the solvent dissolves.
If you are trying to dissolve an oily substance (such as cannabinoids
from pot or oil from lemon peels), look for solvents that will
dissolve oils (e.g. polar solvents, etc.). Be aware that some
solvents may dissolve more than you bargained for. Alcohols and
acetone will dissolve things that petroleum distillates won't, like
sugars and chlorophyll. Another thing to look for is boiling point.
Naptha solvent (coal tar naptha) has a boiling point so high that you
wouldn't be able to boil it off to separate it from THC (the THC
would boil off with it). Solvents with lower boiling points are
much easier to boil off, and usually leave less residual solvent.
Petroleum distillates are usually a mixture of various hydrocarbons
with a variety of boiling points. The boiling fraction of any
particular petroleum distillate refers to the range of boiling points
of its components.
PURITY: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
There are basically two ways that impurities can get into solvents,
etc. The first way is inherent in the manufacturing process. Very
few products are pure at the time of manufacture. The general idea
is to produce a product that meets certain minimum purity
requirements. The product is refined to remove contaminants until
the minimum purity level is reached. Most manufacturing methods
favor low cost production over purity of product. Industrial grade
products are used in applications that require only marginal purity.
With reagent grade chemicals, however, a high degree of purity is
required. Reagent grades are refined until they are ridiculously
pure (e.g. something like 99.999% pure). This additional refining is
costly, and as a result, reagent grades are usually many times the
price of industrial grades. Industrial grades are used in a lot of
commercial products, and are often available at hardware stores, etc.
Reagent grades are generally only available at chemical supply
stores. Unfortunately, most kitchen chemists would have a difficult
time bluffing their way in a chem shop without arousing suspicion.
Additionally, many reagent grade products are watched closely by
certain government agencies, where the industrial grades are not.
(e.g. acetone)
The other way impurities can be introduced is when the manufacturer
intentionally places additives into a product to enhance its
performance (or appearance) or to dilute an expensive component.
Since the performance enhancing additives usually cost more, the
expensive, big brand names are the ones most likely to use them.
When performance enhancing additives are present, the product labels
often boast a lot of features. The less expensive, more generic
looking products are less likely to add performance enhancers but are
more likely to dilute their product. Some additives may actually be
useful, however. e.g. Paint and varnish removers often combine
methylene chloride with methyl alcohol, and furniture refinishers
often have toluene combined with methyl alcohol.
When dealing with industrial grades, always read the label carefully
to determine if it contains things you don't want. Unfortunately,
not all products list every component on their labels. Try calling
the emergency accidental poisoning numbers listed on the labels.
Tell them your dog ingested some of their product, and that the vet
asked you to call the number. Try to get as much information from
them as you can about what the product contains. Work up a likely
story (including symptoms) before you place the call. One crude
method of testing for contaminants in solvents would be to place a
few drops on some clean glass, and let it evaporate. The amount of
residue remaining gives a very rough idea of how much other crud is
in the solvent. Feed a generous amount of this residue to the
neighbor's cat, and if it dies, the product may be too toxic.
Actually, the likelyhood that contaminants in an industrial grade
product are highly toxic or carcinogenic is probably much lower than
most people think. Relatively few substances are highly toxic and/or
significantly carcinogenic. Many things in our everyday environment
are carcinogenic if you are exposed to massive quantities, but potent
carcinogens are not all that common. Due to government regulations,
many (if not most) industrial grade products are not allowed to
contain significant amounts of dangerous substances, anyway. (Who
wants a cleaner or solvent that will leave a highly hazardous
residue?) Even with all of these assurances, there is always a
certain amount of risk associated with the use of industrial grade
products.
In order to reduce the risks associated with contaminants, the
following precautions are in order:
1) use reagent grades when possible
2) if reagent grades cannot be obtained, then make every effort
to acquire the purest product available (read labels, study
manufacturing methods, etc.)
3) purify the product (if you can) before using it
4) use minimal amounts of these products (a liter of solvent
boiled down to a few cc's may still contain a liter's worth
of contaminants)
Some people recommend purifying petroleum distillates by adding
water, shaking vigorously for a long time, and then discarding the
water. This will only help remove water soluble contaminants. A
better way to purify most liquids is to distill them. Unfortunately,
this is not always easy to do if you don't have the right equipment.
One thing I have been intending to try is to shake paint stripper
(containing methyl alcohol and methylene chloride) with a generous
quantity of water to see if I can separate the methylene chloride.
If anyone has comments on whether this will work, please let me know.
USEFUL HINTS: . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Boiling off solvents with low boiling points (less than 100 C):
Place the solvent into a small pan or shallow, wide mouth jar.
Shallow containers with wide openings aid in allowing the vapors to
escape quickly. Place the container with the solvent into a larger
pan of simmering water. Don't allow the water to come to a full
boil. Boiling water is really no hotter than simmering water.
Rapidly boiling water can splash into your solvent, or cause the
solvent container to tip over. Watch the level of the solvent as it
boils away so that the container won't get too light, and tip over.
If the level of the solvent is too low (i.e. 1 cm below the level of
the water), then remove some of the water. Anchoring the solvent
container in place may help. Use hot pads to avoid burning yourself.
Remember to use good ventilation to avoid the build-up of toxic or
flamable fumes. If the boiling point of your solvent is too close to
100 C, you can add sugar or automobile antifreeze to the simmering
water to raise it's boiling point a little, or use the method below
for higher boiling point solvents.
Boiling off solvents with higher boiling points (greater than 100 C):
Follow the method and precautions for lower boiling point solvents
with the following differences: Use melted shortening (or vegetable
oil if you don't have shortening) instead of simmering water. If
your solvent container is glass, place it in the shortening as soon
as it is melted, and then heat it up from there. This will help keep
the jar from cracking. Elevate the solvent container slightly from
the bottom of the larger pan to aid in even heating. A few nails in
the bottom of the shortening works for me. Place a candy thermometer
in the shortening to measure it's temperature. Heat the shortening
until it is 20 or 30 degrees centigrade hotter than the highest
boiling point of your solvent or until the solvent begins to boil at
a comfortable rate. Always keep the temperature of the shortening
well below the boiling point of the dissolved product you are trying
to recover, or you may loose significant amounts of it to
evaporation. Be careful to not let solvent or water splash into the
hot shortening or you may get some spattering of hot grease. If your
solvent container is glass, allow it to cool slowly when you are done
to keep it from cracking. If you are extracting cannabinoids or
other oils of similar or higher boiling points, you may want to raise
the temperature of the shortening to about 160 C for a minute or two
to help eliminate solvent residue. (It can be tough to get rid of
all of it, though.)
Preventing boil-overs:
Some solvents may have a tendency to boil over quite easily. This
can waste valuable product as well as pose fire hazards, etc. By
making sure that the solvent level is well below the top of its
container, many boil-overs may be avoided. It is common practice in
chemistry to use boiling chips to control excessive boiling. Glass
marbles can serve the same purpose, and they are easy to get. Put as
many marbles into your solvent as needed to control the boiling.
Marbles may be removed a few at a time as the solvent level drops.
Remember that valuable extract may coat the surface of the marbles.
Wash them with a very small quantity of solvent and add this to the
rest of the solvent when it is mostly boiled off.
Refluxing in the kitchen:
Find a pan with a lid that can be put on upside down, and still
remain stable with a reasonable fit. Place your solvent, etc. into
the pan, and put the lid on upside down. Place ice in the lid. Heat
the solvent until it begins to boil gently. The heat may be applied
directly, or for better temperature control, you may use a method
similar to the ones listed above for boiling off solvents. If you
use hot shortening to apply heat, be careful to not let water from
melting ice or solvent condensing on the sides drip into the hot
grease. Tying a rag around the top of the solvent pan can help. As
the ice melts, scoop out the water and add more ice.
Getting rid of water in oil extracts:
Sometimes water can get into an oil extract when it is purified by
dissolving in petroleum ether, and shaking with water. As the last
of the solvent boils off, the water forms beads in the bottom of the
extract. These beads of water begin to spatter when the extract gets
too hot. By adding a small amount of acetone or alcohol, the water
will tend to evaporate off as the alcohol or acetone is boiled off.
Make sure that the alcohol or acetone is not contaminated with large
amounts of water or this may be counterproductive. This process may
be repeated until all of the water is gone.
REFERENCES: . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
- Dangerous Properties of Industrial Materials, Litton Educational
Publishing, Inc. (got a lot of good information here)
- CRC Handbook of Chemistry and Physics
- The Merck Index
- Some dictionary of technical and scientific terms
- Labels from numerous OTC products
- Comments from people on the 'net (many thanks to contributors)
- The chemistry-extracting file at hyperreal.com
- Things I remembered, but don't know where I read them"
.