64-17-5 Usage
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
Different sources of media describe the History of 64-17-5 differently. You can refer to the following data:
1. 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].
2. Alcohol is produced naturally from the fermentation
of sugars, and it is assumed that prehistoric humans consumed alcohol when eating
fermented fruits. The earliest direct evidence of alcohol consumption dates from the Neolithic
period 10,000 years ago and consists of stone jugs used for holding alcoholic beverages.
Ancient records and art from Egypt, Babylon, Mesopotamia, and other early civilizations
indicate the use of alcohol as a beverage, medicine, and ceremonial drink. Records also show
that the intoxicating effects of alcohol were known for thousands of years b.c.e. Alcoholic
drinks were stored in Egyptian burial tombs, and deities devoted to alcoholic beverages were
worshiped by different civilizations. As the human population expanded, alcoholic drinks
assumed a prominent role in different cultures; for example, numerous references are made to
wine in the Bible. Ancient Islamic alchemists advanced the practice of alcohol production by
using distillation techniques. Distilled alcohols began to appear in the Middle Ages and was used in many remedies and medicines. A common practice by alchemists in different regions
was the preparation of special liquors and brews with healing power. Aqua vitae (water of
life) could refer to brandy, gin, whiskey, wine, or another form of alcoholic depending on the
geographic area.
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
Different sources of media describe the Uses of 64-17-5 differently. You can refer to the following data:
1. 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].
2. One of the most prominent uses of ethyl alcohol is as a fuel additive and increasingly as a fuel itself. Ethyl alcohol is added to gasoline to increase its oxygen content and octane number. In the United States, the Environmental Protection Agency has mandated that oxygenated fuels be used in certain geographic areas to help meet air quality standards for carbon monoxide, especially in winter. A gasoline blended for this purpose may contain a few percent ethyl alcohol. Gasoline blended with ethyl alcohol is called gasohol. A typical gasohol may contain 90% gasoline and 10% ethanol. Gasohol reduces several common air pollutants including carbon monoxide, carbon dioxide, hydrocarbons, and benzene. Conversely, nitrogen oxides increase with gasohol.
3. Ethanol is used primarily as a solvent — animportant industrial solvent for resins, lacquers, pharmaceuticals, toilet preparations,and cleaning agents; in the production of rawmaterials for cosmetics, perfumes, drugs, andplasticizers; as an antifreeze; as an automotive fuel additive; and from ancient times, inmaking beverages. Its pathway to the bodysystem is mainly through the consumption ofbeverages. It is formed by the natural fermentation of corn, sugarcane, and other crops.
4. Suitable for use in the precipitation of nucleic acids.
5. Most ethyl alcohol is used in alcoholic beverages in suitable dilutions. Other uses are as solvent in laboratory and industry, in the manufacture of denatured alcohol, pharmaceuticals (rubbing Compounds, lotions, tonics, colognes), in perfumery, in organic synthesis. Octane booster in gasoline. Pharmaceutic aid (solvent).
6. alcohol (alcohol SD-40; alcohol SDA-40; ethanol; ethyl alcohol) is widely used in the cosmetic industry as an antiseptic as well as a solvent given its strong grease-dissolving abilities. It is often used in a variety of concentrations in skin toners for acne skin, aftershave lotions, perfumes, suntan lotions, and toilet waters. Alcohol dries the skin when used in high concentrations. It is manufactured through the fermentation of starch, sugar, and other carbohydrates.
7. 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.
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
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.
Chemical Properties
Different sources of media describe the Chemical Properties of 64-17-5 differently. You can refer to the following data:
1. In the BP 2009, the term ‘alcohol’; used without other qualification refers to ethanol containing ≥99.5% v/v of C2H6O. The term‘alcohol’, without other qualification, refers to ethanol 95.1–96.9% v/v. Where other strengths are intended, the term ‘alcohol’ or ‘ethanol’is used, followed by the statement of the strength. In the PhEur 6.0, anhydrous ethanol contains not less than 99.5% v/v of C2H6O at 208℃. The term ethanol (96%) is used to describe the material containing water and 95.1–96.9% v/v of C2H6O at 208℃.
2. Ethyl alcohol is a colorless, volatile, flammable
liquid with a sweet, fruity odor. The Odor Threshold is
0.1355 ppm.
3. 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.
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
Definition
Different sources of media describe the Definition of 64-17-5 differently. You can refer to the following data:
1. ChEBI: A primary alcohol that is ethane in which one of the hydrogens is substituted by a hydroxy group.
2. A colorless volatile liquid
alcohol. Ethanol occurs in intoxicating
drinks, in which it is produced by fermentation
of a sugar:
C6H12O6 → 2C2H5OH + 2CO2
Yeast is used to cause the reaction. At
about 15% alcohol concentration (by volume)
the reaction stops because the yeast is
killed. Higher concentrations of alcohol
are produced by distillation.
Apart from its use in drinks, alcohol is
used as a solvent and to form ethanal. Formerly,
the main source was by fermentation
of molasses, but now catalytic
hydration of ethene is used to manufacture
industrial ethanol. See also methylated
spirits.
Indications
Different sources of media describe the Indications of 64-17-5 differently. You can refer to the following data:
1. 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).
2. 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.
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.
Preparation
There are several approaches to the production of ethanol; mainly ethanol is produced by fermentation.
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
General Description
Reagent Alcohol is denatured alcohol that consists of ethanol, isopropyl alcohol and methyl alcohol in the ratio 90:5:5.
Reactivity Profile
It liberates hydrogen when it reacts withmetal; forms acetaldehyde (toxic, flammable)on catalytic vapor phase dehydrogenation;ethyl ether (flammable) on dehydration withH2SO4 or a heterogeneous catalyst such asalumina, silica, SnCl2, MnCl2, or CuSO4;.
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
The toxicity of ethanol is much lower thanthat of methanol or propanol. However, theliterature on the subject is vastly greater thanthat of any other alcohol. This is attributableessentially to its use in alcoholic beverages.There are exhaustive reviews on alcohol toxicity and free-radical mechanisms (Nordmannet al. 1987). The health hazard arises primarily from ingestion rather than inhalation. Ingestion of a large dose, 250–500 mL,can be fatal. It affects the central nervoussystem. Symptoms are excitation, intoxication, stupor, hypoglycemia, and coma — thelatter occurring at a blood alcohol contentof 300–400 0 mg/L. It is reported to have atoxic effect on the thyroid gland (Hegeduset al. 1988) and to have an acute hypotensiveaction, reducing the systolic blood pressurein humans (Eisenhofer et al. 1987). Chronicconsumption can cause cirrhosis of the liver.Inhalation of alcohol vapors can result inirritation of the eyes and mucous membranes.This may happen at a high concentrationof 5000–10,000 ppm. Exposure may resultin stupor, fatigue, and sleepiness. There isno report of cirrhosis occurring from inhalation. Chronic exposure to ethanol vapors hasproduced brain damage in mice. The neurotoxicity increases with thiamine deficiency(Phillips 1987). Both acute and chronic dosesof ethanol elevated the lipid peroxidation inrat brain. This was found to be elevated further by vitamin E deficiency, as well as itssupplementation (Nadiger et al. 1988).pplementation (Nadiger et al. 1988).The toxicity of ethanol is enhanced in thepresence of compounds such as barbiturates,carbon monoxide, and methyl mercury. Withthe latter compound, ethanol enhanced theretention of mercury in the kidney of ratsand thus increased nephrotoxicity (McNeilet al. 1988). When combined with cocaineand fed to rats, increased maternal and fetaltoxicity was observed (Church et al. 1988).Ethanol is reported to be synergisticallytoxic with caffeine (Pollard 1988) andwith n-butanol and isoamyl alcohol. Priorethanol consumption increased the toxicity of acetaminophen in mice (Carter1987).
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.
Contact allergens
Ethanol is widely used for its solvent and antiseptic
properties. It is rather an irritant and sensitization has
rarely been reported.
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 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
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
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.
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.
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.
Shipping
UN1170 Ethyl alcohol or Ethanol or Ethanol
solutions or Ethyl alcohol solutions, Hazard Class: 3;
Labels: 3-Flammable liquid.
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.
Incompatibilities
In acidic conditions, ethanol solutions may react vigorously with
oxidizing materials. Mixtures with alkali may darken in color
owing to a reaction with residual amounts of aldehyde. Organic
salts or acacia may be precipitated from aqueous solutions or
dispersions. Ethanol solutions are also incompatible with aluminum
containers and may interact with some drugs.
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.
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.
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.
Check Digit Verification of cas no
The CAS Registry Mumber 64-17-5 includes 5 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 2 digits, 6 and 4 respectively; the second part has 2 digits, 1 and 7 respectively.
Calculate Digit Verification of CAS Registry Number 64-17:
(4*6)+(3*4)+(2*1)+(1*7)=45
45 % 10 = 5
So 64-17-5 is a valid CAS Registry Number.
InChI:InChI=1/C2H6O/c1-2-3/h3H,2H2,1H3
64-17-5Relevant articles and documents
An efficient Ni-Mo-K sulfide catalyst doped with CNTs for conversion of syngas to ethanol and higher alcohols
Wang, Ji-Jie,Xie, Jian-Rong,Huang, Yan-Hui,Chen, Bing-Hui,Lin, Guo-Dong,Zhang, Hong-Bin
, p. 44 - 51 (2013)
A type of Ni-Mo-K sulfide catalyst doped with CNTs for conversion of syngas to ethanol and higher alcohols was developed, and displayed high activity and selectivity for direct synthesis of C1-4-alcohols, especially ethanol, from syngas. Over a Ni0.5Mo1K0.5- 15%CNTs catalyst under the reaction conditions of 8.0 MPa and 593 K, the S(total oxy.) reached 64.1% (CO2-free), with the corresponding STY(total oxy.) being 113 mg h-1 g-1. Ethanol was the dominant product, with S(EtOH) and STY(EtOH) reaching 33.1% (CO2-free) and 55.6 mg h-1 g-1, respectively. This STY(EtOH)-value was 1.47 times that (37.9 mg h-1 g-1) of the CNTs-free counterpart under the same reaction conditions. Addition of a minor amount of CNTs to the sulfurized Ni0.5Mo1K0.5 catalyst caused little change in the Ea for the hydrogenation-conversion of syngas. Appropriately reducing CNT's grain-size could improve its capability to adsorb hydrogen, thus increasing CO hydrogenation-conversion, yet did not influence selectivity of the products. The present work demonstrated that CNTs as promoter function through their adsorbing/activating H2 to generate a surface micro-environment with higher stationary-state concentration of H-adspecies on the functioning catalyst. This resulted in a dramatic increase, at the surface of the functioning catalyst, of the molar percentage of catalytically active Mo4+/Mo5+ species in the total amounts of surface Mo. On the other hand, those active H-species adsorbed at the CNTs surface could be readily transferred to NiiMojK k active sites via the CNT-assisted hydrogen spillover. The aforementioned two factors both were conducive to increasing the rate of hydrogenation conversion of syngas.
Production of bio-ethanol by consecutive hydrogenolysis of corn-stalk cellulose
Chu, Dawang,Xin, Yingying,Zhao, Chen
, p. 844 - 854 (2021)
Current bio-ethanol production entails the enzymatic depolymerization of cellulose, but this process shows low efficiency and poor economy. In this work, we developed a consecutive aqueous hydrogenolysis process for the conversion of corn-stalk cellulose to produce a relatively high concentration of bio-ethanol (6.1 wt%) without humin formation. A high yield of cellulose (ca. 50 wt%) is extracted from corn stalk using a green solvent (80 wt% 1,4-butanediol) without destroying the structure of the lignin. The first hydrothermal hydrogenolysis step uses a Ni–WOx/SiO2 catalyst to convert the high cumulative concentration of cellulose (30 wt%) into a polyol mixture with a 56.5 C% yield of ethylene glycol (EG). The original polyol mixture is then subjected to subsequent selective aqueous-phase hydrogenolysis of the C–O bond to produce bioethanol (75% conversion, 84 C% selectivity) over the modified hydrothermally stable Cu catalysts. The added Ni component favors the good dispersion of Cu nanoparticles, and the incorporated Au3+ helps to stabilize the active Cu0-Cu+ species. This multi-functional catalytic process provides an economically competitive route for the production of cellulosic ethanol from raw lignocellulose.
Laser-Microstructured Copper Reveals Selectivity Patterns in the Electrocatalytic Reduction of CO2
Ackerl, Norbert,Martín, Antonio J.,Pérez-Ramírez, Javier,Veenstra, Florentine L. P.
, p. 1707 - 1722 (2020)
-
Photochemical Preparation of Anatase Titania Supported Gold Catalyst for Ethanol Synthesis from CO2 Hydrogenation
Wang, Dong,Bi, Qingyuan,Yin, Guoheng,Wang, Peng,Huang, Fuqiang,Xie, Xiaoming,Jiang, Mianheng
, p. 11 - 22 (2018)
Abstract: Hydrogenation of the greenhouse gas CO2 to higher alcohols through catalysis holds great promise for resource transformation in low-carbon energy supply system, but the efficient and selective synthesis of value-added ethanol by a robust heterogeneous catalyst under relatively mild conditions remains a major challenge. Based on our previous work on Au/TiO2 as an active and selective catalyst for ethanol synthesis, we report here that a facile photochemical route can be used for the preparation of anatase TiO2 supported gold catalyst (Au/a-TiO2) for efficient hydrogenation of CO2. Compared with the conventional deposition-precipitation method requiring strong br?nsted base and flammable H2 gas in the complicated and time-consuming process, the photochemical way for the facile preparation of supported gold catalyst shows the advantages of green and energy-saving. Of significant importance is that an impressive space-time-yield of 869.3?mmol?gAu?1?h?1, high selectivity, and excellent stability can be readily attained at 200?°C and total pressure of 6?MPa. The effects of irradiation time, solvent, and metal loading or Au particle size on ethanol synthesis are systematically investigated. Graphical Abstract: [Figure not available: see fulltext.].
Fe/Fe3C Boosts H2O2 Utilization for Methane Conversion Overwhelming O2 Generation
Xing, Yicheng,Yao, Zheng,Li, Wenyuan,Wu, Wenting,Lu, Xiaoqing,Tian, Jun,Li, Zhongtao,Hu, Han,Wu, Mingbo
, p. 8889 - 8895 (2021)
H2O2 as a well-known efficient oxidant is widely used in the chemical industry mainly because of its homolytic cleavage into .OH (stronger oxidant), but this reaction always competes with O2 generation resulting in H2O2 waste. Here, we fabricate heterogeneous Fenton-type Fe-based catalysts containing Fe-Nx sites and Fe/Fe3C nanoparticles as a model to study this competition. Fe-Nx in the low spin state provides the active site for .OH generation. Fe/Fe3C, in particular Fe3C, promotes Fe-Nx sites for the homolytic cleavages of H2O2 into .OH, but Fe/Fe3C nanoparticles (Fe0 as the main component) with more electrons are prone to the undesired O2 generation. With a catalyst benefiting from finely tuned active sites, 18 % conversion rate for the selective oxidation of methane was achieved with about 96 % selectivity for liquid oxygenates (formic acid selectivity over 90 %). Importantly, O2 generation was suppressed 68 %. This work provides guidance for the efficient utilization of H2O2 in the chemical industry.
Kinetics of hydrogenation of acetic acid to ethanol
Chen, Qiang,Zhang, Xuebing,Tian, Shuxun,Long, Junying,Meng, Xiangkun,Sun, Qi,Li, Yonglong
, p. 2915 - 2923 (2019)
The intrinsic kinetic behaviour of catalytic hydrogenation of acetic acid in vapour phase was studied over a multi-metallic catalyst. The rate expression was derived from the sequence of elementary reaction steps based on a Langmuir-Hinshelwood-model involving two types of active sites. Experiments were carried out in a fixed bed reactor, which is similar to an isothermal integral reactor designed to excluding the negative effects of internal and external diffusion. The reaction conditions investigated were as follow:reaction temperature 275-325 oC, reaction pressure1.5-3.0 MPa, liquid hourly space velocity (sv) 0.3-1.2 h-1, molar ratio of hydrogen to acetic acid (H/AC) 8:20. The results show that conversion of acetic acid increases with increasing the reaction temperature and pressure, but decreases with increasing the space velocity and H/AC. Furthermore, reducing the reaction pressure and increasing reaction temperature, space velocity and H/AC can improve the reaction selectivity of acetic acid to ethanol. The established kinetic model results agreed with experimental results. The relative difference between the calculated value and the experimental value is less than 6 %. The values of model parameters are consistent with the three thermodynamic constraints. The study provided evidence that the intrinsic kinetic model is suitable both mathematically and thermodynamically, and it could be useful in guiding reactor design and optimization of operating conditions.
-
Jatkar,Gajendragad
, p. 798 (1937)
-
Porous Copper Microspheres for Selective Production of Multicarbon Fuels via CO2 Electroreduction
Zou, Chengqin,Xi, Cong,Wu, Deyao,Mao, Jing,Liu, Min,Liu, Hui,Dong, Cunku,Du, Xi-Wen
, (2019)
The electroreduction of carbon dioxide (CO2) toward high-value fuels can reduce the carbon footprint and store intermittent renewable energy. The iodide-ion-assisted synthesis of porous copper (P-Cu) microspheres with a moderate coordination number of 7.7, which is beneficial for the selective electroreduction of CO2 into multicarbon (C2+) chemicals is reported. P-Cu delivers a C2+ Faradaic efficiency of 78 ± 1% at a potential of ?1.1 V versus a reversible hydrogen electrode, which is 32% higher than that of the compact Cu counterpart and approaches the record (79%) reported in the same cell configuration. In addition, P-Cu shows good stability without performance loss throughout a continuous operation of 10 h.
Encapsulation of Two Potassium Cations in Preyssler-Type Phosphotungstates: Preparation, Structural Characterization, Thermal Stability, Activity as an Acid Catalyst, and HAADF-STEM Images
Hayashi, Akio,Ota, Hiromi,López, Xavier,Hiyoshi, Norihito,Tsunoji, Nao,Sano, Tsuneji,Sadakane, Masahiro
, p. 11583 - 11592 (2016)
Dipotassium cation (K+)-encapsulated Preyssler-type phosphotungstate, [P5W30O110K2]13-, was prepared by heating monobismuth (Bi3+)-encapsulated Preyssler-type phosphotungstate, [P5W30O110Bi(H2O)]12-, in acetate buffer in the presence of an excess amount of potassium cations. Characterization of the isolated potassium salt, K13[P5W30O110K2] (1a), and its acid form, H13[P5W30O110K2] (1b), by single crystal X-ray structure analysis, 31P and 183W nuclear magnetic resonance (NMR), Fourier transform infrared (FT-IR) spectroscopy, cyclic voltammetry (CV), high-resolution electrospray ionization mass spectroscopy (HR-ESI-MS), and elemental analysis revealed that two potassium cations are encapsulated in the Preyssler-type phosphotungstate molecule with formal D5h symmetry, which is the first example of a Preyssler-type compound with two encapsulated cations. Incorporation of two potassium cations enhances the thermal stability of the potassium salt, and the acid form shows catalytic activity for hydration of ethyl acetate. Packing of the Preyssler-type molecules was observed by high-resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM).
Anderson et al.
, p. 2418,2422 (1952)
Hydrolysis of S-2-aminoethylcysteinyl peptide bond by Achromobacter protease I.
Masaki,Takiya,Tsunasawa,Kuwahara,Sakiyama,Soejima
, p. 215 - 216 (1994)
The substrate specificity of Achromobacter protease I (API) was examined for S-2-aminoethyl(AE)cysteinyl bonds in Bz-AEC-OMe/OEt, Bz-AEC-NH2, and AE-insulin B chain. The protease hydrolyzed all of the tested AE-cysteinyl bonds at the same rate as that of lysyl bonds. Kinetic parameters were estimated for this hydrolysis reaction.
CO2 Hydrogenation to Ethanol over Cu@Na-Beta
Ding, Liping,Shi, Taotao,Gu, Jing,Cui, Yun,Zhang, Zhiyang,Yang, Changju,Chen, Teng,Lin, Ming,Wang, Peng,Xue, Nianhua,Peng, Luming,Guo, Xuefeng,Zhu, Yan,Chen, Zhaoxu,Ding, Weiping
, p. 2673 - 2689 (2020)
Here, we report a high-performance catalyst Cu@Na-Beta, prepared via a unique method to embed 2~5 nm Cu nanoparticles in crystalline particles of Na-Beta zeolite, for CO2 hydrogenation to ethanol as the only organic product in a traditional fixed-bed reactor. The ethanol yield in a single pass can reach ~14% at 300°C, ~12,000 mL·gcat?1·h?1, and 2.1 MPa, corresponding to a space-time yield of ~398 mg·gcat?1·h?1. The key step of the reaction is considered as the rapid bonding of CO2? with surface methyl species at step sites of Cu nanoparticles to CH3COO? that converts to ethanol in following hydrogenation steps. The points of the catalyst seemed to be that the irregular copper nanoparticles stuck in zeolitic frameworks offer high density of step sites and the intimate surrounding of zeolitic frameworks strongly constrain the CO2 reactions at the copper surface and block by-products, such as methanol, formic acid, and acetyl acid. The high-performance catalyst Cu@Na-Beta, prepared via a unique method to embed 2~5 nm Cu nanoparticles in crystalline particles of Na-Beta zeolite, is reported for CO2 hydrogenation to ethanol as the only organic product in a traditional fixed-bed reactor. The ethanol yield in a single pass can reach ~14% at 300°C, ~12,000 mL·gcat?1·h?1, and 2.1 MPa, corresponding to space-time yield of ~398 mg·gcat?1·h?1. The key step of the reaction is the rapid bonding of CO2? with surface methyl species at step sites of Cu nanoparticles to CH3COO?, which converts to ethanol in the following hydrogenation steps. The points of the catalyst seem to be that the irregular copper nanoparticles stuck in zeolitic frameworks offer a high density of step sites and that the intimate surrounding of zeolitic frameworks strongly constrains the CO2 reactions at the copper surface and blocks byproducts such as methanol, formic acid, and acetyl acid. CO2 direct reduction to ethanol is a much-anticipated research topic worldwide. A big progress has been made in the current investigation toward industry application. A high-performance catalyst Cu@Na-Beta, prepared via a unique method to embed 2~5 nm Cu nanoparticles in crystalline particles of Na-Beta zeolite, is reported for CO2 hydrogenation to ethanol in a traditional fixed-bed reactor, with ethanol space-time yield of ~398 mg·gcat?1·h?1. Peripherals-surrounded catalysts, which may be called mesocatalysts, appear to be one focus of future investigations on catalysis.
Active sites in CO2 hydrogenation over confined VOx-Rh catalysts
Wang, Guishuo,Luo, Ran,Yang, Chengsheng,Song, Jimin,Xiong, Chuanye,Tian, Hao,Zhao, Zhi-Jian,Mu, Rentao,Gong, Jinlong
, p. 1710 - 1719 (2019)
Metal oxide-promoted Rh-based catalysts have been widely used for CO2 hydrogenation, especially for the ethanol synthesis. However, this reaction usually suffers low CO2 conversion and alcohols selectivity due to the formation of byp
-
Roberts,Yancey
, p. 5943 (1952)
-
Reduction of Potassium Acetate and Potassium Propionate With Lithium Aluminium Hydride in the Presence of Phase-Transfer Catalysts
Szakacs, Sandor,Goeboeloes, Sandor,Szammer, Janos
, p. 883 - 886 (1981)
Ethyl alcohol and propyl alcohol can be prepared with good yields from potassium carboxylates by the reduction with lithium aluminium hydride in the presence of different phase transfer catalysts. - Keywords: Crown ethers; Phase-transfer catalysts; Reduction
Effect of the ZnO/SiO2ratio on the structure and catalytic activity of Cu/SiO2and Cu/ZnO catalysts in water-containing ester hydrogenation
Chen, Zheng,Wei, Shuwei,Zhao, Xueying,Wang, Dengfeng,Chen, Jiangang
, p. 14560 - 14567 (2020)
The effects of the ZnO/SiO2 ratio on the water tolerance of Cu/SiO2 and Cu/ZnO catalysts were studied by ethyl acetate with 5 wt% water hydrogenation. Notably, the addition of an appropriate amount of ZnO endows Cu/SiO2 catalysts with satisfactory water-tolerant hydrogenation performance by a decrease in the reaction temperature without sacrificing conversion. At the same time, agglomeration can be alleviated for Cu/ZnO catalysts due to the optimal addition of SiO2, which is considered as a partition material that effectively hinders the agglomeration of the Cu/ZnO catalyst. However, the addition of ZnO was not favourable for the copper dispersion of Cu/SiO2. The stability of Cu/SiO2 catalyst quickly degraded due to excessive ZnO being introduced by sintering. The copper dispersion of Cu/ZnO catalysts initially increased with increasing SiO2 content, but then decreased. The addition of excess SiO2 also led to decreased activity and rapid deactivation of the Cu/ZnO catalyst. In our study, the appropriate addition of ZnO (5 wt%) and SiO2 (5 wt%) had a positive effect on the Cu/SiO2 and Cu/ZnO catalysts, respectively.
Near-infrared kinetic spectroscopy of the HO2and C 2H5O2 self-reactions and cross reactions
Noell,Alconcel,Robichaud,Okumura,Sander
, p. 6983 - 6995 (2010)
The self-reactions and cross reactions of the peroxy radicals C 2H5O2 and HO2 were monitored using simultaneous independent; spectroscopic probes to observe each radical species. Wavelength modulation (WM) near-infrared (NIR) spectroscopy was used to detect HO 2, and UV absorption monitored C2H2O 2. The temperature dependences of these reactions were investigated over a range of interest; to tropospheric chemistry, 221-296 K. The Arrhenius expression determined for the cross reaction, k2(T) = (6.01 +1.95 -1.47) x 10-13 exp((638 ± 73)/T) cm3 molecules-1 s-1 is in agreement with other work from the literature. The measurements of the HO2 self-reaction agreed with previous work from, this lab and were not further refined. The C2H5O2 self-reaction is complicated by secondary production of HO2. This experiment performed the first direct measurement of the self-reaction rate constant, as well as the branching fraction to the radical channel, in part; by measurement of the secondary HO2. The Arrhenius expression for the self-reaction rate constant is k3(T) = (1.29 +0.34 -0.27) x 10-13 exp((-23 ± 61)/T) cm3 molecules-1 s- and the branching fraction value is α = 0.28 ± 0.06, independent of temperature. These values are in disagreement with previous measurements based on end product studies of the blanching fraction. The results suggest that better characterization of the products from RO2 self-reactions are required.
Photoinduction of Cu single atoms decorated on UiO-66-NH2for enhanced photocatalytic reduction of CO2to liquid fuels
Wang, Gang,He, Chun-Ting,Huang, Rong,Mao, Junjie,Wang, Dingsheng,Li, Yadong
, p. 19339 - 19345 (2020)
Photocatalytic reduction of CO2 to value-added fuels is a promising route to reduce global warming and enhance energy supply. However, poor selectivity and low efficiency of catalysts are usually the limiting factor of their applicability. Herein, a photoinduction method was developed to achieve the formation of Cu single atoms on a UiO-66-NH2 support (Cu SAs/UiO-66-NH2) that could significantly boost the photoreduction of CO2 to liquid fuels. Notably, the developed Cu SAs/UiO-66-NH2 achieved the solar-driven conversion of CO2 to methanol and ethanol with an evolution rate of 5.33 and 4.22 μmol h-1 g-1, respectively. These yields were much higher than those of pristine UiO-66-NH2 and Cu nanoparticles/UiO-66-NH2 composites. Theoretical calculations revealed that the introduction of the Cu SAs on the UiO-66-NH2 greatly facilitates the conversion of CO2 to CHO? and CO? intermediates, leading to excellent selectivity toward methanol and ethanol. This study provides new insights for designing high-performance catalyst for photocatalytic reduction of CO2 at the atomic scale.
Cu9-Alx-Mgy catalysts for hydrogenation of ethyl acetate to ethanol
Tian, Jingxia,Hu, Jun,Shan, Wenjuan,Wu, Peng,Li, Xiaohong
, p. 108 - 115 (2017)
Cu9-Alx or Cu9-Alx-My (M?=?Mg, Ca, Ba or Sr) catalysts were prepared by a deposition-precipitation method, characterized by means of H2-TPR, XRD and N2 sorption, and applied for hydrogenation of ethyl acetate to ethanol in a fixed-bed reactor. The molar ratio of Cu/Al or Cu/Al/M and the reaction parameters were investigated thoroughly. As a result, the Cu9-Al0.5-Mg1.5 catalyst with higher specific surface area, lower initial reduction temperature and better metal dispersion furnished 97.8% ethyl acetate conversion with 98% selectivity to ethanol under optimal reaction conditions. Moreover, the Cu9-Al0.5-Mg1.5 catalyst also showed good lifetime and neither the activity nor selectivity decreased during 210?h test. Based on the characterization of the Cu9-Al0.5-Mg1.5 catalyst, the optimal Cu+/Cu0 proportion played a key role in determining the superior performance.
Insight into the Correlation between Cu Species Evolution and Ethanol Selectivity in the Direct Ethanol Synthesis from CO Hydrogenation
Li, Xiao-Li,Yang, Guo-Hui,Zhang, Meng,Gao, Xiao-Feng,Xie, Hong-Juan,Bai, Yun-Xing,Wu, Ying-Quan,Pan, Jun-Xuan,Tan, Yi-Sheng
, p. 1123 - 1130 (2019)
Cu/SiO2 catalyst was prepared by the ammonia evaporation method for the direct synthesis of ethanol from CO hydrogenation. The catalyst exhibited the initial ethanol selectivity as high as 40.0 wt %, which dramatically decreased from 40.0 to 9.6 wt % on the stream of 50 h. XRD, XPS, TEM and N2O titration techniques were employed to elucidate the ethanol selectivity change and catalyst structure evolution during reaction process. The experiment and characterization results indicated that both Cu+/(Cu++Cu0) value and copper crystallite size had great effects on the ethanol selectivity. During the initial 38 h, the ethanol selectivity obviously decreased from 40.0 to 18.2 wt %, and Cu+/(Cu++Cu0) value on the catalyst surface rapidly dropped from 0.67 to 0.39, while the copper crystallite size remained almost unchanged. However, during the reaction period of 38–50 h, the Cu+/(Cu++Cu0) value possessed no distinct change, but a further decrease in ethanol selectivity and a rapid aggregation in Cu particles were observed simultaneously. The present systematic investigation demonstrated that the decrease of Cu+/(Cu++Cu0) value was the main factor for the loss of ethanol selectivity during the initial 38 h, whereas the rapid growth of Cu particles during the reaction period of 38–50 h were mainly contributed to the further decline of ethanol selectivity.
Synthesis, characterization, thermogravimetry, and structural study of uranium complexes derived from dibasic S-alkylated thiosemicarbazone ligands
Fasihizad, Ahad,Barak, Tahere,Ahmadi, Mehdi,Dusek, Michal,Pojarova, Michaela
, p. 2160 - 2170 (2014)
Two pentagonal bipyramidal complexes, ethanol-(S-ethyl-N1,N 4-bis(3-methoxy-2-hydroxybenzaldehyde)-isothiosemicarbazide-N,N',O, O')-dioxidouranium(VI) (1) and ethanol-(S-ethyl-N1-(2- hydroxyacetophenone)-N4-(5-bromo-2-hydroxybenzaldehyde)- isothiosemicarbazide-N,N',O,O')-dioxidouranium(VI) (2), have been prepared and characterized. Their structures have been determined by X-ray crystallography, and the structural parameters are discussed with those observed in related complexes. Electronic absorption, proton magnetic resonance, and FT-IR spectra have been recorded and analyzed. In both complexes, the U(VI) centers are surrounded by N2O2 donor ligands, two oxido groups, and one ethanol in a distorted pentagonal bipyramid. The thermal stability of the new complexes has also been determined. 2014
Lemay,Ouellet
, p. 1316 (1955)
Efficient methane electrocatalytic conversion over a Ni-based hollow fiber electrode
Chen, Wei,Dong, Xiao,Guo, Zhikai,Li, Guihua,Song, Yanfang,Sun, Yuhan,Wei, Wei
, p. 1067 - 1072 (2020)
Natural gas and shale gas, with methane as the main component, are important and clean fossil energy resources. Direct catalytic conversion of methane to valuable chemicals is considered a crown jewel topic in catalysis. Substantial studies on processes including methane reforming, oxidative coupling of methane, non-oxidative coupling of methane, etc. have been conducted for many years. However, owing to the intrinsic chemical inertness of CH4, harsh reaction conditions involving either extremely high temperatures or highly oxidative reactants are required to activate the C–H bonds of CH4 in such thermocatalytic processes, which may cause the target products, such as ethylene or methanol, to be further converted into coke or CO and CO2. It is desirable to adopt a new strategy for direct CH4 conversion under mild conditions. Herein, we report that efficient electrocatalytic oxidation of methane to alcohols at ambient temperature and pressure can be achieved using a NiO/Ni hollow fiber electrode. This work opens a new avenue for direct catalytic conversion of CH4.
Hydrogenation of carbon dioxide to methanol by using a homogeneous ruthenium-phosphine catalyst
Wesselbaum, Sebastian,Vom Stein, Thorsten,Klankermayer, Juergen,Leitner, Walter
, p. 7499 - 7502 (2012)
Simply efficient: The homogenously catalyzed hydrogenation of CO 2 to methanol is achieved by using a ruthenium phosphine complex under relatively mild conditions (see scheme; HNTf2= bis(trifluoromethane)sulfonimide). This is the first example of CO2 hydrogenation to methanol by using a single molecularly defined catalyst. Copyright
Nitric oxide as an activation agent for nucleophilic attack in trans-[Ru(NO)(NH3)4{P(OEt)3}](PF 6)3
Metzker, Gustavo,Toledo Jr., Jose? C.,Lima, Francisco C. A.,Magalha?es, Alvicler,Cardoso, Daniel R.,Franco, Douglas W.
, p. 1266 - 1273 (2010)
The complex trans-[Ru(NO)(NH3)4{P(OEt) 3}](PF6)3 undergoes nucleophilic attack on the phosphorus ester ligand in the solid state yielding trans-[Ru(NO)(NH 3)4{P(OH)(OEt)2/s
Selectively chemo-catalytic hydrogenolysis of cellulose to EG and EtOH over porous SiO2 supported tungsten catalysts
Fan, Maohong,Mu, Shifang,Sun, Qi,Wang, Haiyong,Wang, Xiaolong,Wang, Yan,Weng, Yujing,Zhang, Mingwei,Zhang, Yulong
, (2022/03/15)
Cellulosic ethanol produced from lignocellulose biomass can alleviate the shortage of conventional fossil energy supply and reduce global CO2 emissions. Wherein, hydrogenolysis of cellulose to ethanol is a new method for the synthesis of fuel ethanol, which could theoretically utilizes all carbon atoms in glucose in the direct retro-aldol condensation (RAC) reaction to produce ethanol, and can potentially break through the technical bottleneck of biological methods. Herein, we show that the benefits of the mesoporous structure of tungsten-based catalysts can be leveraged to influence the selective hydrogenolysis of cellulose into C2 products. Comparing the performance of different pore size SiO2 supported tungsten catalysts and detailed characterizations revealed that the mesoporous structure of supports can affect the morphology, crystal sizes, and surface chemistry of the catalysts, which presented a combined effect on the hydrogenolysis reaction. Whereby, 51.5 wt% ethylene glycol (EG) was obtained from the direct hydrogenolysis of cellulose over Ru-WOx/SiO2 (500 ?) catalyst under 513 K, and 40.5 wt% ethanol (EtOH) was obtained from the direct hydrogenolysis of cellulose over Ir-WOx/SiO2 (500 ?) catalyst under 553 K, respectively.
Stable ethanol synthesis via dimethyl oxalate hydrogenation over the bifunctional rhenium-copper nanostructures: Influence of support
Chen, Xingkun,Ding, Yunjie,Du, Zhongnan,Li, Zheng,Lin, Ronghe,Wang, Shiyi,Wang, Xuepeng,Zhu, Hejun
, p. 241 - 252 (2022/02/22)
Addition of oxophilc rhenium to decorate small copper nanoparticles has been validated to be an efficient method to prepare a low-copper catalyst for the direct synthesis of ethanol via dimethyl oxalate (DMO) hydrogenation process, and herein we investigated the impact of supports on the catalytic performance of ReCu catalysts. A series of materials including activated carbon (AC), Al2O3, SiO2, TiO2 and ZrO2 were utilized as the support and as prepared Re2Cu5 catalysts were evaluated. The results exhibited that the Re2Cu5/ZrO2 catalyst possesses the highest DMO hydrogenation activity and ethanol yield (~93%), which may be due to its lowest Cu0/Cu+ ratio (0.13), smallest Cu particle size (~0.84 nm) a relative high reduction degree (59%). The CO adsorption behavior characterized by in situ IR spectroscopy showed that a strong metal-support interaction creates an electron deficient environment of Cu nanoparticle, resulting in a lower Cu0/Cu+ ratio that enhances the activation of C[dbnd]O bond in the DMO molecular.
(Hexamethylbenzene)Ru catalysts for the Aldehyde-Water Shift reaction
Phearman, Alexander S.,Moore, Jewelianna M.,Bhagwandin, Dayanni D.,Goldberg, Jonathan M.,Heinekey, D. Michael,Goldberg, Karen I.
supporting information, p. 1609 - 1615 (2021/03/09)
The Aldehyde-Water Shift (AWS) reaction uses H2O as a benign oxidant to convert aldehydes to carboxylic acids, producing H2, a valuable reagent and fuel, as its sole byproduct. (Hexamethylbenzene)RuIIcomplexes are demonstrated to have higher activity and selectivity (up to 95%) for AWS over disproportionation than previously reported catalysts.