| Identification | More | [Name]
Etanol | [CAS]
64-17-5 | [Synonyms]
VECTRAPRIME
1-hydroxyethane
Absolute ethanol
absoluteethanol
absoluterAlkohol
Aethanol
Aethylalkohol
Alcare Hand Degermer
Alcohol anhydrous
Alcohol, dehydrated
Alcohol, diluted
alcohol,[combustiblelabel]
alcohol,anhydrous
alcohol,ethyl
alcoholanhydrous
alcoholdehydrated
Alcool ethylique
Alcool etilico
alcoolethylique
alcoolethylique(french) | [EINECS(EC#)]
200-578-6 | [Molecular Formula]
C2H6O | [MDL Number]
MFCD08064666 | [Molecular Weight]
46.0684 | [MOL File]
64-17-5.mol |
| Chemical Properties | Back Directory | [Appearance]
Ethyl alcohol is a colorless, volatile, flammable
liquid with a sweet, fruity odor. The Odor Threshold is
0.1355 ppm. | [Melting point ]
-114°C | [Boiling point ]
78°C | [density ]
0.789 g/mL at 20 °C | [vapor density ]
1.59 (vs air) | [vapor pressure ]
43 mmHg at 20 °C | [FEMA ]
2419 | [refractive index ]
1.3614 | [Fp ]
12°C | [storage temp. ]
Store at RT. | [solubility ]
water: soluble (completely) | [form ]
Liquid. Colorless liquid / invisible vapor. | [pka]
16(at 25℃) | [color ]
APHA: ≤10 | [Specific Gravity]
0.80872～0.81601 | [Odor]
Pleasant alcoholic odor detectable at 49 to 716 ppm (mean = 180 ppm) | [PH]
7.0 (10g/l, H2O, 20℃) | [Relative polarity]
0.654 | [Stability:]
Stable. Substances to be avoided include strong oxidizing agents, peroxides, acids, acid chlorides, acid anhydrides, alkali metals, ammonia, moisture. Forms explosive mixtures with air. Hygroscopic. | [explosive limit]
3.1-27.7%(V)(ethanol) | [Odor Threshold]
0.52ppm | [Odor Type]
alcoholic | [Water Solubility ]
miscible | [Sensitive ]
Hygroscopic | [λmax]
λ: 240 nm Amax: 0.40
λ: 250 nm Amax: 0.30
λ: 260 nm Amax: 0.30
λ: 270 nm Amax: 0.10
λ: 340 nm Amax: 0.10 | [Detection Methods]
GC | [JECFA Number]
41 | [Merck ]
14,3760 | [BRN ]
1718733 | [Dielectric constant]
24.3（25℃） | [Exposure limits]
TLV-TWA 1900 mg/m3 (1000 ppm)
(ACGIH). | [Contact allergens]
Ethanol is widely used for its solvent and antiseptic
properties. It is rather an irritant and sensitization has
rarely been reported. | [LogP]
-0.19 | [Uses]
ethyl alcohol (Etanol) is commonly known as rubbing alcohol. ethyl alcohol is ordinary alcohol and is used medicinally as a topical antiseptic, astringent, and anti-bacterial. At concentrations above 15 percent, it is also a broad-spectrum preservative against bacteria and fungi, and can boost the efficacy of other preservatives in a formulation. Cosmetic companies tend to use alcohol SD-40 in high-grade cosmetic manufacturing as they consider ethanol too strong and too drying for application on the skin. obtained from grain distillation, it can also be synthetically manufactured. | [CAS DataBase Reference]
64-17-5(CAS DataBase Reference) | [IARC]
1 (Vol. 96, 100E) 2012 | [NIST Chemistry Reference]
Ethanol(64-17-5) | [EPA Substance Registry System]
64-17-5(EPA Substance) |
| Hazard Information | Back Directory | [Chemical Properties]
Ethyl alcohol is a colorless flammable liquid with a typical lower alcohol odor and is miscible
in water in all proportions. It is stable and hygroscopic. It is incompatible with strong
oxidizing agents, peroxides, acids, acid chlorides, acid anhydrides, alkali metals, ammonia,
and moisture. Ethyl alcohol forms explosive mixtures with air. Ethyl alcohol is the
most common solvent used in aerosols, cosmetics, pharmaceuticals, alcoholic beverages,
vinegar production, and in the chemical synthesis of a large variety of products in different
industries. For instance, in the manufacture of plastics, lacquers, polishes, plasticizers,
perfumes, adhesives, rubber accelerators, explosives, synthetic resins, nitrocellulose, inks,
preservatives, and as a fuel. | [Definition]
ChEBI: A primary alcohol that is ethane in which one of the hydrogens is substituted by a hydroxy group. | [General Description]
A clear colorless liquid with a characteristic vinous odor and pungent taste. Flash point 55°F. Density 6.5 lb/gal. Vapors are heavier than air. | [Reactivity Profile]
ETHANOL(64-17-5) reacts violently with acetyl chloride and acetyl bromide [Rose, (1961); Merck 11th ed., 1989]. Mixtures with concentrated sulfuric acid and strong hydrogen peroxide can cause explosions. Mixtures with concentrated hydrogen peroxide form powerful explosives. Reacts readily with hypochlorous acid and with chlorine to give ethyl hypochlorite, which decomposes in the cold and explodes on exposure to sunlight or heat. Base-catalysed reactions with isocyanates should be carried out in inert solvents. Such reactions in the absence of solvents often occur with explosive violence [Wischmeyer(1969)]. Highly oxidized potassium metal was dropped into a dish of ethyl alcohol, an immediate explosion shattered the dish. Potassium superoxide was considered the cause of the reaction [Health and Safety Inf. 251(1967)]. ETHANOL(64-17-5) or mETHANOL(64-17-5) can ignite on contact with a platinum-black catalyst. (Urben 1794). | [Air & Water Reactions]
Highly flammable. Soluble in water in all proportions. | [Hazard]
Classified as a depressant drug. Though it
is rapidly oxidized in the body and is therefore noncumulative, ingestion of even moderate amounts
causes lowering of inhibitions, often succeeded by
dizziness, headache, or nausea. Larger intake causes
loss of m | [Health Hazard]
Exposures to ethyl alcohol by ingestion cause dizziness, faintness, drowsiness, decreased
awareness and responsiveness, euphoria, abdominal discomfort, nausea, vomiting, staggering
gait, lack of coordination, and coma. Ethyl alcohol causes no adverse effects with normal
skin, but is potentially harmful when absorbed across markedly abraded skin. Repeated
inhalation of ethyl alcohol vapors in high concentrations may cause a burning sensation in
the throat and nose, stinging and watering in the eyes with symptoms of irritation, dizziness,
faintness, drowsiness, nausea, and vomiting. Direct exposures of the eyes to ethyl alcohol
may cause mild to moderate conjunctivitis, seen mainly as redness of the conjunctiva.
Prolonged and repeated oral exposures to ethyl alcohol result in the development of
progressive liver injury with fi brosis. Chronic exposures or repeated ingestion of ethyl
alcohol by pregnant women are known to adversely affect the CNS of the fetus, producing
a collection of effects that together constitute fetal alcohol syndrome. The adverse
health effects observed in the fetus include mental and physical retardation, disturbances
of learning, motor, and language defi ciencies, small size head, and behavioral disorders.
The target organs that are damaged by prolonged exposures to ethyl alcohol include the
eyes, skin, respiratory system, CNS, liver, blood, and reproductive system. | [Health Hazard]
VAPOR: Irritating to eyes, nose and throat. LIQUID: Not harmful. | [Potential Exposure]
Ethyl alcohol is used, topical antiinfective agent; solvent to make beverages; in the chemical
synthesis of a wide variety of compounds, such as acetaldehyde, ethyl ether, ethyl chloride, and butadiene. It is a solvent
or processing agent in the manufacture of pharmaceuticals;
plastics, lacquers, polishes, plasticizers, perfumes, cosmetics,
rubber accelerators; explosives, synthetic resins; nitrocellulose, adhesives, inks, and preservatives. It is also used as an
antifreeze and as a fuel. It is an intermediate in the manufacture of many drugs and pesticides. | [Fire Hazard]
FLAMMABLE. Flashback along vapor trail may occur. Vapor may explode if ignited in an enclosed area. | [First aid]
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least
15 minutes, occasionally lifting upper and lower lids. Seek
medical attention immediately. If this chemical contacts the
skin, remove contaminated clothing and wash immediately
with soap and water. Seek medical attention immediately.
If this chemical has been inhaled, remove from exposure,
begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical
facility. When this chemical has been swallowed, get medical attention. Give large quantities of water and induce
vomiting. Do not make an unconscious person vomit | [Shipping]
UN1170 Ethyl alcohol or Ethanol or Ethanol
solutions or Ethyl alcohol solutions, Hazard Class: 3;
Labels: 3-Flammable liquid. | [Incompatibilities]
May form explosive mixture with air.
May accumulate static electrical charges, and may cause
ignition of its vapors. Reactions may be violent with oleum,
sulfuric acid; nitric acid, bases, aliphatic amines;isocyanates, strong oxidizers. Also incompatible with potassium dioxide, bromine pentafluoride; acetyl bromide; acetyl
chloride; platinum, sodium. | [Description]
Ethyl alcohol, also called ethanol, absolute alcohol, or grain alcohol, is a clear, colorless, flammable
liquid with a pleasant odor. It is associated primarily with alcoholic beverages, but it
has numerous uses in the chemical industry. The word alcohol is derived from the Arabic
word al kuhul, which was a fine powder of the element antimony used as a cosmetic. In
Medieval times, the word al kuhul came to be associated with the distilled products known
as alcohols. The hydroxyl group, -OH, bonded to a carbon, characterizes alcohols. Ethyl is
derived from the root of the two-carbon hydrocarbon ethane. | [Waste Disposal]
Dissolve or mix the material
with a combustible solvent and burn in a chemical incinerator equipped with an afterburner and scrubber. All federal,
state, and local environmental regulations must be
observed. Consult with environmental regulatory agencies
for guidance on acceptable disposal practices. Generators
of waste containing this contaminant (≥100 kg/mo) must
conform with EPA regulations governing storage, transportation, treatment, and waste disposal.
| [Occurrence]
Reported found in apple, apple aroma, apple essence, apple juice, bacon fat, banana, bean, beef fat, beef extract,
blackberry, black currant, bread, brussels sprout, cabbage, carrot root, cauliflower, blue cheese, cheddar cheese, Swiss cheese, cocoa
bean, cherry, coffee, cream, cucumber, alcoholic beverages and many other sources | [Indications]
Ethanol is the most widely abused drug in the world.
There are more than 10 million alcoholics in the United
States alone. Excessive consumption of alcoholic beverages
has been linked to as many as half of all traffic accidents,
two-thirds of homicides, and three-fourths of
suicides, and it is a significant factor in other crimes, in
family problems, and in personal and industrial accidents.
The annual cost to the American economy has
been estimated to exceed $100 billion in lost productivity,
medical care, and property damage.
Alcoholism has been difficult to define because of its
complex nature.A person is generally considered an alcoholic,
however, when his or her lifestyle is dominated
by the procurement and consumption of alcoholic beverages
and when this behavior interferes with personal,
professional, social, or family relations.
A light drinker generally is defined as one who consumes
an average of one drink or less per day, usually
with the evening meal; a moderate drinker is one who
has approximately three drinks per day; and a heavy
drinker is one who has five or more drinks per day (or
in the case of binge drinkers, at least once per week with
five or more drinks on each occasion). | [Indications]
Intravenous use of ethanol, while once widely employed
to inhibit premature labor, is now of historical interest
only. Ethanol inhibits oxytocin release from the pituitary
and thus indirectly decreases myometrial contractility.
Today, 2-adrenomimetics and magnesium sulfate have
replaced ethanol for parenteral tocolysis. | [Preparation]
There are several approaches to the production of ethanol; mainly ethanol is produced by fermentation. | [Production Methods]
Ethanol is manufactured by the controlled enzymatic fermentation
of starch, sugar, or other carbohydrates. A fermented liquid is
produced containing about 15% ethanol; ethanol 95% v/v is then
obtained by fractional distillation. Ethanol may also be prepared by
a number of synthetic methods. | [Brand name]
Absolute alcohol;Alcohol aethylicus;Alcool;Avitoin;Banatol;B-tonin;Colfin;Desqyam-x;Duonale-e;Efatin;Equithesin;Hizeneck-d;Honkon-n;Kapsitrin;Keralyt;Levovinizol;Mikrozid;Neotizol;Panoxy;Papette;Piadarn;Polislerol;Protectaderm;Sicol;Sodaphilline;Softa man;Sotracarix;Verucid;Weingeist;Xeracin. | [World Health Organization (WHO)]
Ethanol has been used throughout recorded history both in a
medicinal and a social context. It is currently included in pharmaceutical
preparations either as an active or inactive ingredient. At pharmacologically active
doses ethanol is both a powerful cerebral depressant and a drug of addiction. Its
use in pharmaceutical preparations has been severely restricted in several
countries and in 1986 the 39th World Health Assembly adopted a resolution to
prohibit such use except when ethanol is an essential ingredient which cannot be
replaced by an appropriate alternative. | [Aroma threshold values]
Detection: 8 to 900 ppb
| [Flammability and Explosibility]
Ethanol is a flammable liquid (NFPA rating = 3), and its vapor can travel a considerable distance to an ignition source and "flash back." Ethanol vapor forms explosive mixtures with air at concentrations of 4.3 to 19% (by volume). Hazardous gases produced in ethanol fires include carbon monoxide and carbon dioxide. Carbon dioxide or dry chemical extinguishers should be used for ethanol fires. | [Chemical Reactivity]
Reactivity with Water No reaction; Reactivity with Common Materials: No reaction; Stability During Transport: Stable; Neutralizing Agents for Acids and Caustics: Not pertinent; Polymerization: Not pertinent; Inhibitor of Polymerization: Not pertinent. | [Pharmaceutical Applications]
Ethanol and aqueous ethanol solutions of various concentrations are widely used in pharmaceutical
formulations and cosmetics. Although ethanol is
primarily used as a solvent, it is also employed as a disinfectant, and
in solutions as an antimicrobial preservative. Topical ethanol
solutions are used in the development of transdermal drug delivery
systems as penetration enhancers. Ethanol has also been used
in the development of transdermal preparations as a co-surfactant. | [Biochem/physiol Actions]
Positive allosteric modulator of GABAA receptors, and negative allosteric modulator of NMDA glutamate receptors. | [Mechanism of action]
A great deal of attention has been focused on a class of
proteins termed the ligand-gated ion channels as being
important to the mechanism of action of alcohol.These
integral membrane proteins function as gates or pores
that allow the passage of certain ions into and out of
neurons upon binding of the appropriate neurotransmitter.
This flux of ions largely determines the degree of
neuronal activity. Two distinct types of ligand-gated
ion channels are particularly sensitive to concentrations
of alcohol that produce intoxication and sedation.
These are the α-aminobutyric acid (GABA) chloride
ionophore and the N-methyl-D-aspartate (NMDA) subtype
of glutamate receptor. The GABA–chloride ion
channel reduces neuronal activity by hyperpolarizing
the neurons, while activation of the NMDA receptor
causes neuronal depolarization or excitation. Alcohol
has been shown to increase chloride flux through the
GABAA receptor and reduce calcium flux through the
NMDA receptor. These actions result in powerful suppression
of nerve cell activity, which is consistent with
the depressant actions of alcohol in the brain. | [Clinical Use]
Generally, no treatment is required for acute ethanol intoxication.
Allowing the individual to sleep off the effects
of ethanol ingestion is the usual procedure.
Hangovers are treated similarly; that is, no effective
remedy exists for a hangover, except for controlling the
amount of ethanol consumed. Sometimes ethanol overdose
is a medical emergency. For example, prompt treatment
is required if the patient is in danger of dying of
respiratory arrest, is comatose, has dilated pupils, is hypothermic,
or displays tachycardia.
Treatment for severe ethanol overdose is generally
supportive. Increased intracranial pressure can be relieved
by intravenous administration of hypertonic
mannitol. Hemodialysis can accelerate the removal of
ethanol from the body. Stimulants of ethanol metabolism,
such as fructose, are not sufficiently effective, and
use of analeptics is not recommended because of the possibility
of precipitating convulsions.
The immediate concern in the treatment of alcoholics is
detoxification and management of the ethanol withdrawal
syndrome. Another pharmacological approach is the use of anticraving
drugs, for example serotonin uptake inhibitors,dopaminergic agonists, and opioid antagonists.The only
treatment that has shown considerable promise is one
that uses the opioid antagonist naltrexone. | [Side effects]
Acute Ethanol Intoxication and Hangover
Ethanol intoxication is probably the best-known form
of drug toxicity. Intoxicated individuals are a threat to
themselves and others, particularly if they attempt to
drive or operate machinery. Although death can result
from ethanol overdose, usually the patient lapses into a
coma before ingesting lethal quantities. Ethanol intoxication
is sometimes mistakenly diagnosed as diabetic
coma, schizophrenia, overdosage of other CNS depressant
drugs, or skull fracture. An additional feature commonly
associated with excessive ethanol consumption is
difficulty in regulating body temperature. Hypothermia
frequently results, with body temperature falling toward
that of the ambient environment. This problem can be
particularly severe in the elderly, who normally have
difficulty regulating their body temperature.
One of the consequences of ethanol intoxication is
the hangover, a condition characterized by headache,
nausea, sweating, and tremor. Although unpleasant, a
hangover is not dangerous, even though the person having
one may feel otherwise. | [Safety]
Ethanol and aqueous ethanol solutions are widely used in a variety
of pharmaceutical formulations and cosmetics. It is also consumed
in alcoholic beverages.
Ethanol is rapidly absorbed from the gastrointestinal tract and
the vapor may be absorbed through the lungs; it is metabolized,
mainly in the liver, to acetaldehyde, which is further oxidized to
acetate.
Ethanol is a central nervous system depressant and ingestion of
low to moderate quantities can lead to symptoms of intoxication
including muscle incoordination, visual impairment, slurred speech,
etc. Ingestion of higher concentrations may cause depression of
medullary action, lethargy, amnesia, hypothermia, hypoglycemia,
stupor, coma, respiratory depression, and cardiovascular collapse.
The lethal human blood-alcohol concentration is generally estimated
to be 400–500 mg/100 mL.
Although symptoms of ethanol intoxication are usually encountered
following deliberate consumption of ethanol-containing
beverages, many pharmaceutical products contain ethanol as a
solvent, which, if ingested in sufficiently large quantities, may cause
adverse symptoms of intoxication. In the USA, the maximum
quantity of alcohol included in OTC medicines is 10% v/v for
products labeled for use by people of 12 years of age and older, 5%
v/v for products intended for use by children aged 6–12 years of age,
and 0.5% v/v for products for use by children under 6 years of
age.
Parenteral products containing up to 50% of alcohol (ethanol 95
or 96% v/v) have been formulated. However, such concentrations
can produce pain on intramuscular injection and lower concentrations
such as 5–10% v/v are preferred. Subcutaneous injection of
alcohol (ethanol 95% v/v) similarly causes considerable pain
followed by anesthesia. If injections are made close to nerves,
neuritis and nerve degeneration may occur. This effect is used
therapeutically to cause anesthesia in cases of severe pain, although
the practice of using alcohol in nerve blocks is controversial. Doses
of 1mL of absolute alcohol have been used for this purpose.
Preparations containing more than 50% v/v alcohol may cause
skin irritation when applied topically.
LD50 (mouse, IP): 0.93 g/kg
LD50 (mouse, IV): 1.97 g/kg
LD50 (mouse, oral): 3.45 g/kg
LD50 (mouse, SC): 8.29 g/kg
LD50 (rat, IP): 3.75 g/kg
LD50 (rat, IV): 1.44 g/kg
LD50 (rat, oral): 7.06 g/kg | [Carcinogenicity]
In 1987, the International Agency
for Research on Cancer (IARC) evaluated the cancer data on
ethanol and alcoholic beverages in humans and animals
. The IARC concluded that there was inadequate
evidence for the carcinogenicity of ethanol and of alcoholic
beverages in experimental animals, but there was sufficient
evidence for the carcinogenicity of alcoholic beverages in
humans. The IARC classified alcoholic beverages as a Group
1 carcinogen based on the occurrence of malignant tumors of
the oral cavity, pharynx, larynx, esophagus, and liver that
have been causally related to the consumption of alcoholic
beverages. | [Environmental Fate]
If released to the environment from natural or anthropogenic
sources, ethanol will preferentially partition to the soil, water,
and air. Bioconcentration and bioaccumulation potential
is anticipated to be low based upon the estimated bioconcentration
factor and experimental octanol/water partition
coefficient. If released into water, ethanol’s half-life is less than
10 days. The half-life upon release to air is less than 5 days,
where wet deposition removal predominates. Biodegradation
and volatilization are expected to be important fate and
transport processes for ethanol. | [Purification Methods]
Usual impurities of fermentation alcohol are fusel oils (mainly higher alcohols, especially pentanols), aldehydes, esters, ketones and water. With synthetic alcohol, likely impurities are water, aldehydes, aliphatic esters, acetone and diethyl ether. Traces of *benzene are present in ethanol that has been dehydrated by azeotropic distillation with *benzene. Anhydrous ethanol is very hygroscopic. Water (down to 0.05%) can be detected by formation of a voluminous precipitate when aluminium ethoxide in *benzene is added to a test portion, Rectified spirit (95% ethanol) is converted to absolute (99.5%) ethanol by refluxing with freshly ignited CaO (250g/L) for 6hours, standing overnight and distilling with precautions to exclude moisture. Numerous methods are available for further drying of absolute ethanol for making “Super dry ethanol”. Lund and Bjerrum [Chem Ber 64 210 1931] used reaction with magnesium ethoxide, prepared by placing 5g of clean dry magnesium turnings and 0.5g of iodine (or a few drops of CCl4), to activate the Mg, in a 2L flask, followed by 50-75 mL of absolute ethanol, and warming the mixture until a vigorous reaction occurs. When this subsides, heating is continued until all the magnesium is converted to magnesium ethoxide. Up to 1L of ethanol is then added and, after an hour's reflux, it is distilled off. The water content should be below 0.05%. Walden, Ulich and Laun [Z Phys Chem 114 275 1925] used amalgamated aluminium chips, prepared by degreasing aluminium chips (by washing with Et2O and drying in a vacuum to remove grease from machining the Al), treating with alkali until hydrogen evolved vigorously, washing with H2O until the washings were weakly alkaline and then stirring with 1% HgCl2 solution. After 2minutes, the chips were washed quickly with H2O, then alcohol, then ether, and dried with filter paper. (The amalgam became warm.) These chips were added to the ethanol, which was then gently warmed for several hours until evolution of hydrogen ceased. The alcohol was distilled and aspirated for some time with pure dry air. Smith [J Chem Soc 1288 1927] reacted 1L of absolute ethanol in a 2L flask with 7g of clean dry sodium, and added 25g of pure ethyl succinate (27g of pure ethyl phthalate was an alternative), and refluxed the mixture for 2hours in a system protected from moisture, and then distilled the ethanol. A modification used 40g of ethyl formate instead, so that sodium formate separated out and, during reflux, the excess of ethyl formate decomposed to CO and ethanol. Drying agents suitable for use with ethanol include Linde type 4A molecular sieves, calcium metal, and CaH2. The calcium hydride (2g) is crushed to a powder and dissolved in 100mL absolute ethanol by gently boiling. About 70mL of the ethanol are distilled off to remove any dissolved gases before the remainder is poured into 1L of ca 99.9% ethanol in a still, where it is boiled under reflux for 20hours, while a slow stream of pure, dry hydrogen (better use nitrogen or Ar) is passed through. It is then distilled [Rüber Z Elektrochem 29 334 1923]. If calcium is used for drying, about ten times the theoretical amount should be used, and traces of ammonia (from some calcium nitride in the Ca metal) would be removed by passing dry air into the vapour during reflux. Ethanol can be freed from traces of basic materials by distillation from a little 2,4,6-trinitrobenzoic acid or sulfanilic acid. *Benzene can be removed by fractional distillation after adding a little water (the *benzene/water/ethanol azeotrope distils at 64.9o), the alcohol is then re-dried using one of the methods described above. Alternatively, careful fractional distillation can separate *benzene as the *benzene/ethanol azeotrope (b 68.2o). Aldehydes can be removed from ethanol by digesting with 8-10g of dissolved KOH and 5-10g of aluminium or zinc per L, followed by distillation. Another method is to heat under reflux with KOH (20g/L) and AgNO3 (10g/L) or to add 2.5-3g of lead acetate in 5mL of water to 1L of ethanol, followed (slowly and without stirring) by 5g of KOH in 25mL of ethanol: after 1hour the flask is shaken thoroughly, then set aside overnight before filtering and distilling. The residual water can be removed by standing the distillate over activated aluminium amalgam for 1 week, then filtering and distilling. Distillation of ethanol from Raney nickel eliminates catalyst poisons. Other purification procedures include pre-treatment with conc H2SO4 (3mL/L) to eliminate amines, and with KMnO4 to oxidise aldehydes, followed by refluxing with KOH to resinify aldehydes, and distilling to remove traces of H3PO4 and other acidic impurities after passage through silica gel, and drying over CaSO4. Water can be removed by azeotropic distillation with dichloromethane (azeotrope boils at 38.1o and contains 1.8% water) or 2,2,4-trimethylpentane. [Beilstein 1 IV 1289.] Rapid purification: Place degreased Mg turnings (grease from machining the turnings is removed by washing with dry EtOH then Et2O, and drying in a vacuum) (5g) in a dry 2L round bottomed flask fitted with a reflux condenser (protect from air with a drying tube filled with CaCl2 or KOH pellets) and flush with dry N2. Then add iodine crystals (0.5g) and gently warm the flask until iodine vapour is formed and coats the turnings. Cool, then add EtOH (50mL) and carefully heat to reflux until the iodine disappears. Cool again then add more EtOH (to 1L) and reflux under N2 for several hours. Distil and store over 3A molecular sieves (pre-heated at | [Toxicity evaluation]
Upon acute exposure ethanol is a central nervous system (CNS)
depressant that initially and selectively depresses some of the
most active portions of the brain (reticular activity system and
cortex). The mechanism of action most likely involves interference
with ion transport at the axonal cell membrane rather
than at the synapse, similar to the action of other anesthetic
agents. Ethanol can bind directly to the gamma-aminobutyric
acid receptor in the CNS and cause sedative effects. Ethanol
may also have direct effects on cardiac muscle, thyroid tissue,
and hepatic tissue.
Chronic and excessive ethanol ingestion has been associated
with a wide range of adverse effects. At the cellular level
these effects can be attributable to metabolic intermediates.
Ethanol is metabolized differently at low and high concentrations.
At low ethanol blood levels ethanol is metabolized very
efficiently by alcohol dehydrogenase to acetaldehyde and then
by aldehyde dehydrogenase to acetate producing nicotinamide
adenine dinucleotide (NADH) in both reactions.
Chronic high ethanol intake induces the cytochrome P450
mediated MEOS, which can be predominant. Under these
conditions ethanol is metabolized to acetaldehyde without reducing NADH. The MEOS pathway utilizes nicotinamide
adenine dinucleotide phosphate thus producing an oxidative
environment, which decreases the reducing equivalents present
in the cell, increasing oxidative stress. This pathway has been
associated with the release of highly reactive oxygen species in
addition to acetaldehyde, which contributes to the hepatic
damage observed in chronic alcohol abuse.
Acetaldehyde has been implicated as one significant
contributor to the toxicity observed in chronic ethanol overexposure
(see Acetaldehyde). Acetaldehyde is highly reactive
and can interact with DNA and proteins to form stable adducts.
These DNA adducts may induce mutations, although there is
an absence of direct evidence that they are in fact the initiators
of cancers associated with alcohol ingestion. Acetaldehyde and
malondialdehyde, a product of ethanol-induced lipid peroxidation,
can form protein adducts which have been found in
the serum of alcoholics and rats fed ethanol. These adducts are
capable of eliciting an immune response believed to be
important in the inflammatory processes observed in alcoholic
liver disease and possibly neurotoxicity. | [Regulatory Status]
Included in the FDA Inactive Ingredients Database (dental
preparations; inhalations; IM, IV, and SC injections; nasal and
ophthalmic preparations; oral capsules, solutions, suspensions,
syrups, and tablets; rectal, topical, and transdermal preparations).
Included in the Canadian List of Acceptable Non-medicinal
Ingredients. Included in nonparenteral and parenteral medicines
licensed in the UK. |
| Safety Data | Back Directory | [Hazard Codes ]
F,T,Xn | [Risk Statements ]
R11:Highly Flammable.
R10:Flammable.
R36/37/38:Irritating to eyes, respiratory system and skin .
R39/23/24/25:Toxic: danger of very serious irreversible effects through inhalation, in contact with skin and if swallowed .
R23/24/25:Toxic by inhalation, in contact with skin and if swallowed .
R68/20/21/22:Harmful: possible risk of irreversible effects through inhalation, in contact with skin and if swallowed .
R20/21/22:Harmful by inhalation, in contact with skin and if swallowed .
R52/53:Harmful to aquatic organisms, may cause long-term adverse effects in the aquatic environment . | [Safety Statements ]
S16:Keep away from sources of ignition-No smoking .
S7:Keep container tightly closed .
S36:Wear suitable protective clothing .
S26:In case of contact with eyes, rinse immediately with plenty of water and seek medical advice .
S45:In case of accident or if you feel unwell, seek medical advice immediately (show label where possible) .
S36/37:Wear suitable protective clothing and gloves .
S61:Avoid release to the environment. Refer to special instructions safety data sheet .
S24/25:Avoid contact with skin and eyes . | [RIDADR ]
1170 | [WGK Germany ]
nwg | [RTECS ]
KQ6300000 | [Autoignition Temperature]
363 °C | [TSCA ]
Yes | [HazardClass ]
3 | [PackingGroup ]
II | [HS Code ]
22071000 | [storage]
Ethyl alcohol should be protected from physical damage. It should be kept stored in a cool,
dry, well-ventilated location, away from any area where the fi re hazard may be acute.
Outside or detached storage is preferred. Separate from incompatibles. Containers should
be bonded and grounded for transfer to avoid static sparks. The storage and use areas
should be free from smoking areas. | [Precautions]
During handling of ethyl alcohol, workers should use chemical-resistant shields, monogoggles,
proper gloves, laboratory coat/apron, and protective equipment as required. Workers
and the workplace should have adequate ventilation vent hoods, class b extinguisher.
Workers should avoid sources of heat, sparks, or flames. Waste disposal and spill should be
collected in suitable containers or absorbed on a suitable absorbent material for subsequent
disposal. Waste material should be disposed of in an approved incinerator or in a designated
landfi ll site, in compliance with all federal, provincial, and local government regulations. | [Safety Profile]
Confirmed human
carcinogen for ingestion of beverage
alcohol. Experimental tumorigenic and
teratogenic data. Moderately toxic to
humans by ingestion. Moderately toxic
experimentally by intravenous and
intraperitoneal routes. Mildly toxic by
inhalation and skin contact. Human systemic
effects by ingestion and subcutaneous
routes: sleep disorders, hallucinations,
dtstorted perceptions, convulsions, motor
activity changes, ataxia, coma, antipsychotic,headache, pulmonary changes, alteration in
gastric secretion, nausea or vomiting, other
gastrointestinal changes, menstrual cycle
changes, and body temperature decrease.
Can also cause glandular effects in humans.
Human reproductive effects by ingestion,
intravenous, and intrauterine routes: changes
in female fertility index. Effects on newborn
include: changes in Apgar score, neonatal
measures or effects, and drug dependence.
Experimental reproductive effects. Human
mutation data reported. An eye and skin
irritant.
The systemic effect of ethanol differs
from that of methanol. Ethanol is rapidly
oxidtzed in the body to carbon dtoxide and
water, and, in contrast to methanol, no
cumulative effect occurs. Though ethanol
possesses narcotic properties,
concentrations sufficient to produce this
effect are not reached in industry.
Concentrations below 1000 pprn usually
produce no signs of intoxication. Exposure
to concentrations over 1000 pprn may cause
headache, irritation of the eyes, nose, and
throat, and, if continued for an hour,
drowsiness and lassitude, loss of appetite,
and inability to concentrate. There is no
concrete evidence that repeated exposure to
ethanol vapor results in cirrhosis of the liver.
Ingestion of large doses can cause alcohol
poisoning. Repeated ingestions can lead to
alcoholism. It is a central nervous system
depressant.Flammable liquid when exposed to heat or flame; can react vigorously with oxidizers. To fight fire, use alcohol foam, CO2, dry
chemical. Explosive reaction with the
oxidized coating around potassium metal.
Ignites and then explodes on contact with
acetic anhydride + sodum hydrogen sulfate.
Reacts violently with acetyl bromide
(evolves hydrogen bromide),
dichloromethane + sulfuric acid + nitrate or
nitrite, disulfuryl difluoride, tetrachlorosilane
+ water, and strong oxidants. Ignites on
contact with disulfuric acid + nitric acid,
phosphorus(IⅡ) oxide, platinum, potassium tert-butoxide + acids. Forms explosive
products in reaction with ammonia + silver
nitrate (forms silver nitride and silver
fulminate), magnesium perchlorate (forms
ethyl perchlorate), nitric acid + silver (forms
silver fulminate), silver nitrate (forms ethyl
nitrate), silverp) oxide + ammonia or
hydrazine (forms silver nitride and silver
fulminate), sodum (evolves hydrogen gas).
Incompatible with acetyl chloride, BrF5,
Ca(OCl)2, ClO3, Cr03, Cr(OCl)2, (cyanuric
acid + H20), H202, HNO3, (H202 +
H2SO4), (I + CH3OH + HgO), wn(ClO4)2
+ 2,2-dimethoxy propane], Hg(NO3)2,
HClO4, perchlorates, (H2SO4 + permanganates), HMn04, KO2, KOC(CH3)3, AgClO4,
NaH3N2, uo2(clO4)2
| [Hazardous Substances Data]
64-17-5(Hazardous Substances Data) | [Toxicity]
LD50 in young, old rats (g/kg): 10.6, 7.06 orally (Wiberg) | [IDLA]
3,300 ppm [10% LEL] |
| Questions And Answer | Back Directory | [Introduction]
Ethanol, also known as ethyl alcohol (or grain spirits, or alcohol), is a clear colorless, volatile, flammable solvent with a characteristic odor. The boiling point of ethanal is 78.5°C. The bio-alcohol is found in alcoholic beverages. Concentrated alcohol has a strong burning taste, but it is somewhat sweet when diluted. It is also increasingly being used as a fuel (usually replacing or complementing gasoline). Its low melting point of -114.5° C allows it to be used in antifreeze products.
| [History]
Ethanol has been known to humans since prehistory as the active ingredient of alcoholic beverages. Its isolation as a relatively pure compound was probably achieved first by Islamic alchemists who developed the art of distillation[1].
| [Chemical properties]
Ethanol is highly soluble in water and organic solvents, but poorly soluble in fats and oils. Ethanol itself is a good solvent, which is used in cosmetics, paints and tinctures[2]. Density of ethanol at 68 °F (20 °C) is 789 g/l. Pure ethanol is neutral (pH ~7). Most alcoholic beverages are more or less acidic.
Ethanol/ethyl alcohol is highly flammable liquid, hygroscopic, and fully miscible in water. Ethanol is incompatible with a large number of chemicals such as strong oxidising agents, acids, alkali metals, ammonia, hydrazine, peroxides, sodium, acid anhydrides, calcium hypochlorite, chromyl chloride, nitrosyl perchlorate, bromine pentafluoride, perchloric acid, silver nitrate, mercuric nitrate, potassium tert-butoxide, magnesium perchlorate, acid chlorides, platinum, uranium hexafluoride, silver oxide, iodine heptafluoride, acetyl bromide, disulphuryl difluoride, acetyl chloride, permanganic acid, ruthenium (VIII) oxide, uranyl perchlorate, and potassium dioxide.
| [Production]
Ethanol is produced by fermenting and distilling grains. Actually, ethanol can be made from any plant that contains a large amount of sugar or components that can be converted into sugar, such as starch or cellulose. As their names imply, sugar beets and sugar cane contain natural sugar. Crops such as corn, wheat and barley contain starch that can be easily converted to sugar[3]. Today, ethanol is made primarily from corn.
Another form of ethanol, called bioethanol, can be made from lignocellulosics which are from many types of trees and grasses, although the process is more difficult[4]. Lignocellulose consists of three main components: cellulose, hemicellulose and lignin, the first two being composed of chains of sugar molecules. Those chains can be hydrolyzed to produce monomeric sugars, some of which can be fermented using yeasts to produce ethanol. Ethanol can be produced from lignocellulosic materials in various ways, but all processes comprise the same main components: hydrolysis of the hemicellulose and the cellulose to monomer sugars, fermentation and product recovery and concentration by distillation[5].
Currently, ethanol production processes using crops are well-established. However, utilization of a cheaper substrate, such as lignocellulose, could make bioethanol more competitive with fossil fuel. Therefore, bacterial and yeast strains have been constructed which are advantageous for ethanol production[6]. The cost of ethanol production from lignocellulosic materials is relatively high based on current technologies, and the main challenges are the low yield and high cost of the hydrolysis process. Considerable research efforts have been made to improve the hydrolysis of lignocellulosic materials[7]. Besides, new enzymes have revolutionized the liquefaction process in starch ethanol and improved ethanol yield and product quality[8].
| [Uses]
Medical
A solution of 70-85% of ethanol is commonly used as a disinfectant and it kills organisms by denaturing their proteins and dissolving their lipids. It is effective against most bacteria and fungi, and many viruses, but is ineffective against bacterial spores. This disinfectant property of ethanol is the reason that alcoholic beverages can be stored for a long time[9]. Ethanol also has many medical uses, and can be found in products such as medicines, medical wipes and as an antiseptic in most antibacterial hand sanitizer gels. Ethanal can also be used as antidote. It competitively blocks the formation of toxic metabolites in toxic alcohol ingestions by having a higher affinity for the enzyme Alcohol Dehydrogenase (ADH). Its chief application is in methanol and ethylene glycol ingestions. Ethanol can be administered by the oral, nasogastric or intravenous route to maintain a blood ethanol concentration of 100-150 mg/dl (22-33 mol/L)[10].
Fuel
Ethanol is flammable and burns more cleanly than many other fuels. Ethanol has been used in cars since Henry Ford designed his 1908 Model T to operate on alcohol. In Brazil and the United States, the use of ethanol from sugar cane and grain as car fuel has been promoted by government programs[11]. The Brazilian ethanol program started as a way to reduce the reliance on oil imports, but it was soon realized that it had important environmental and social benefits[12]. The fully combusted products of ethanol are only carbon dioxide and water. For this reason, it is environmental friendly and has been used to fuel public buses in the US. However, pure ethanol attacks certain rubber and plastic materials and cannot be used in unmodified car engines[13].
The alcohol-based alternative fuel that is blended with gasoline to produce a fuel with a higher octane rating and fewer harmful emissions than unblended gasoline. A mixture containing gasoline with at least 10% ethanol is known as gasohol. Specifically, gasoline with 10% ethanol content is known as E10. Another common gasohol variant is E15, which contains 15% ethanol and 85% gasoline. E15 is only appropriate for use in Flex Fuel vehicles or a very small percentage of the newest vehicles[14]. In addition, E85 is a term used for a mixture of 15% gasoline and 85% ethanol. E85 keeps the fuel system clean because it burns cleaner than regular gas or diesel and doesn't leave behind gummy deposits. Beginning with the model year 1999, a number of vehicles in the U.S. were manufactured so as to be able to run on E85 fuel without modification. These vehicles are often labeled dual fuel or flexible fuel vehicles, since they can automatically detect the type of fuel and change the engine's behavior to compensate for the different ways that they burn in the engine cylinders[15].
The use of ethanol-diesel fuel blends is growing around the world, and are designed to provide renewable, cleaner burning fuel alternatives for off-road equipment, buses, semi-trucks and other vehicles that run on diesel fuel. With the addition of ethanol and other fuel additives to diesel, the characteristic black diesel smoke is eliminated and there are significant reductions in particulate matter, carbon monoxide, and nitrogen oxide emissions. It is also possible to use ethanol for cooking as a replacement for wood, charcoal, propane, or as a substitute for lighting fuels, such as kerosene[16].
Brazil and the United States lead the industrial production of ethanol fuel, accounting together for 89% of the world's production in 2008. In comparison with the USA and Brazil, Europe ethanol for fuel production is still very modest. Brazil is the world's second largest producer of ethanol fuel and the world's largest exporter[17].
Beverage
Significant volumes of ethanol are produced for the beverage and industrial markets from agricultural feedstock. Ethanol produced for these industries differs from ethanol for fuel only in its strength, which can vary between 96% and 99.9% and in its purity, depending on the end use. Beverage and drinks industry may be the best-known end-user of ethanol. It is used to make many kinds of spirits, such vodka, gin and anisette. High standards and processes are required for ethanal used in the production of spirit drinks.
Others
The ethanol used as an intermediary product by the chemical, pharmaceutical or cosmetics industry is in many cases of the highest and purest possible quality. These are premium markets due to the additional steps in the alcohol production process that are necessary to achieve the required purity. Same high standards and purity requirements apply in food industry, such as flavors and aromas extraction and concentrations, as well as paints and thermometers. Ethanol can be used in de-icer or anti-freeze to clear the car windscreen. It also is contained in perfumes, deodorants, and other cosmetics[18].
| [Safety and hazards]
Even though ethanol is very commonly used, it is a dangerous chemical. As ethanal is highly flammable, it has exact flash points which needs to be noticed. While ethanol is consumed when drinking alcoholic beverages, consuming ethanol alone can cause coma and death. Ethanol may also be a carcinogenic[19].
Exposure to ethanol can be in vapor form (breathing it in), skin/body contact or ingestion. All are serious and need to be managed appropriately to ensure more damage is not incurred while trying to attend to the exposure.
Common side effects of ethanol include: intoxication, low blood pressure (hypotension) with flushing, agitation, low blood sugar (hypoglycemia), nausea, vomiting and excessive urination[20].
| [References]
[1] http://www.bio-medicine.org/biology-definition/Ethyl_alcohol/
[2] http://www.nutrientsreview.com/alcohol/definition-physical-chemical-properties.html
[3] http://large.stanford.edu/courses/2010/ph240/luk1/
[4] http://www.highwaterethanol.com/index.cfm?show=10&mid=24
[5] M. Galbe, G. Zacchi, A review of the production of ethanol from softwood, Applied microbiology and biotechnology, 59(2002) 618-28.
[6] J. Zaldivar, J. Nielsen, L. Olsson, Fuel ethanol production from lignocellulose: a challenge for metabolic engineering and process integration, Applied microbiology and biotechnology, 56(2001) 17-34.
[7] Y. Sun, J. Cheng, Hydrolysis of lignocellulosic materials for ethanol production: a review, Bioresource technology, 83(2002) 1-11.
[8] P.V. Harris, F. Xu, N.E. Kreel, C. Kang, S. Fukuyama, New enzyme insights drive advances in commercial ethanol production, Current opinion in chemical biology, 19(2014) 162-70.
[9] http://www.bio-medicine.org/biology-definition/Ethyl_alcohol/
[10] https://lifeinthefastlane.com/tox-library/antidote/ethanol/
[11] https://www.worldofmolecules.com/fuels/ethanol.htm
[12] J. Goldemberg, Ethanol for a sustainable energy future, science, 315(2007) 808-10.
[13] https://www.worldofmolecules.com/fuels/ethanol.htm
[14] https://www.exxon.com/en/ethanol
[15] http://renewkansas.com/ethanol-advantages-benefits/
[16] http://energybc.ca/biofuels.html
[17] C. Ibeto, A. Ofoefule, K. Agbo, A global overview of biomass potentials for bioethanol production: a renewable alternative fuel, Trends Appl Sci Res, 6(2011) 410e25.
[18] https://www.epure.org/about-ethanol/beverage-industrial-use/
[19] https://www.msdsonline.com/2014/04/21/ethanol-versatile-common-and-potentially-dangerous/
[20] https://www.rxlist.com/consumer_ethanol_alcohol/drugs-condition.htm
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