67-56-1 Usage
Introduction
Methanol is the simplest fatty alcohol. It is a colorless, flammable, irritating liquid with a boiling point of 64.7°C, a melting point of -93.90°C, and a relative density of 0.7913. Soluble in water and most organic solvents. Its severe toxicity can damage the optic nerve. Once swallowed, it can make the eyes blind and even cause death.
Methanol has the general properties of a primary aliphatic alcohol. The three hydrogen atoms on a carbon atom with a hydroxyl group can be oxidized, orderly generating formaldehyde, formic acid, and carbon dioxide. Therefore, it is largely used in the synthesis of formaldehyde. Methanol is easily converted into important organic synthesis intermediates such as methyl carboxylate, methyl chloride and methylamine, and it is also applied as important organic solvents, extraction agents and alcohol denaturants.
Chemical Properties
Different sources of media describe the Chemical Properties of 67-56-1 differently. You can refer to the following data:
1. Methanol is a clear, colorless liquid with a characteristic pungent odor (NTP NIEHS web accessed 2/16/2013). The air odor threshold has been reported as 1500 ppm (approximately 2000mg/m3), much higher than the occupational guidelines.
Methanol (methyl alcohol; wood alcohol) is used extensively as a solvent for lacquers, paints, varnishes, cements, inks, dyes, plastics, and various industrial coatings. Large quantities are used in the production of formaldehyde and other chemical derivatives such as acetic acid, methyl halides and terephthalate, methyl methacrylate, and methylamines. Methanol is also used as a gasoline additive, as a component of lacquer thinners, in antifreeze preparations of the “nonpermanent” type, and in canned heating preparations of jellied alcohol. It is also used in duplicating fluid, in paint removers, and as a cleaning agent. The potential for methanol as a future alternative for gasoline indicates that the use of this chemical will most likely increase rather than decrease. At room temperature, methanol is a colorless liquid with a pungent odor. It is relatively volatile, with a vapor pressure of 96 mmHg and a vapor density of 1.11. It is miscible with water and soluble with other organic solvents. It is found in nature as a fermentation product of wood and as a constituent of some fruits and vegetables.
2. Methanol is a clear, water-white liquid with a mild odor at
ambient temperatures.The air odor threshold for methanol has been reported as
100 ppm . Others have reported that 2000 or 5900 ppm
methanol is barely detectable .
Uses
Different sources of media describe the Uses of 67-56-1 differently. You can refer to the following data:
1. Methanol is an important chemical raw material for fine chemicals. Its carbonylation at 3.5 MPa and 180-200° C in the presence of catalyst can produce acetic acid and further produce acetic anhydride. It reacts with syngas to prepare vinyl acetate in the presence of catalyst; reacts with isobutylene to produce tert-butyl methyl ether; prepare dimethyl oxalate through oxidization and carbonylation, and a further hydrogenation to produce ethylene glycol; reacts with toluene under catalyst and simultaneous oxidization to produce phenylethyl alcohol. It can be used as a good solvent, as a pesticide raw material, as an antifreeze agent, as a fuel and fuel additive (this is receiving increasing attention in environmental protection field). It is the main raw material in the preparation of formaldehyde, the raw material in medicine and spices production, a solvent in dyes and paint industries, the raw material in preparation of methanol single cell protein and synthesis of methyl ester.
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Industry
Applications
Role/Benefit
Laboratory
HPLC, UV/VIS spectroscopy, and LCMS
Low UV cutoff
Chemical manufacture
Production of formaldehyde and its derivates
Main feedstock
Production of hydrocarbon chains and even aromatic systems
Main feedstock
Production of methyl tert-butyl ether
Methylation reagent
Production of dimethyl terephthalic acid, methyl methacrylate and acrylic acid methyl ester
Main feedstock
Plastics
Production of polymers
Main feedstock
Farm chemical
Production of insecticide and acaricide
Main feedstock
Pharmaceuticals
Production of sulfonamides, amycin, etc
Main feedstock
Fuel for vehicles
Pure methanol fuel
Pure methanol does not produce an opaque cloud of smoke in the event of an accident
Methanol gasoline
Blended directly into gasoline to produce a high-octane, efficient fuel with lower emissions than conventional gasoline
Chemical analysis
Determination of boron
Analysis agent
Determination of trace moisture in alcohols, saturated hydrocarbons, benzene, chloroform, pyridine
Analysis agent
Others
Separation of calcium sulfate and magnesium sulfate
Separation reagent
Separation of strontium bromide and barium bromide
Separation reagent
Anti-freezing agent
Effective component
2. Methanol has numerous uses. Its main use is in the production of formaldehyde, whichconsumes approximately 40% of methanol supplies. Methanolis a common organic solvent found in many products including deicers (windshield wiperfl uid), antifreezes, correction fl uid, fuel additives, paints, and other coatings. A number ofindustrial chemicals use methanol in their production. Among these are methyl methacrylateand dimethyl terephthalate. Methanol is used to convert methylacrylamide sulfate to methylmethacrylate and ammonium hydrogen sulfate (NH4HSO4):Methanol is used in making the ester dimethyl terephthalate from mixtures ofxylene of toluene. Dimethyl terephthalate is used in the manufacture of polyesters and plastics.Methanol is used as a fuel additive. The common gasoline additive HEET is pure methanoland is used as a gas-line antifreeze and water remover. Methanol is used as a fuel in camp stoves and small heating devices. It is used to fuel the small engines used in models (airplanes,boats). In the early history of automobiles,methanol was a common fuel. The availability of cheap gasoline replaced methanol in the1920s, but it is receiving renewed interest as an alternative fuel as the demand and cost of oilincrease and oil supplies become uncertain. Methanol can be produced from coal and biomass.Methanol has a higher octane rating and generally lower pollutant emissions compared togasoline. The relatively low flame temperature means that fewer nitrogen oxides are producedby methanol than by ethanol. One large disadvantage of methanol is that it has a lower energydensity than gasoline. Using equivalent volumes of gasoline and methanol, methanol givesabout half the mileage of gasoline. Another problem with methanol is its low vapor pressure,resulting in starting problems on cold days. This problem can be mitigated by using a blendof 85% methanol and 15% gasoline. This mixture is called M85 and is similar to E85 ethanol(see Ethyl Alcohol).
3. Methanol is used in the production offormaldehyde, acetic acid, methyl tert-butylether, and many chemical intermediates; asan octane improver (in oxinol); and as apossible alternative to diesel fuel; being anexcellent polar solvent, it is widely used as acommon laboratory chemical and as a methylating reagent.
4. high purity grade for ICP-MS detection
5. Methylalcohol, CH30H, also known as methanol or wood alcohol, is a colorless, toxic, flammable liquid with a boiling point of 64.6 °C(147 °F). The principal toxic effect is on the nervous system,particularly the retinae. Methyl alcoholis miscible in all proportions with water,ethyl alcohol, and ether. It burns with a light blue flame producing water and carbon dioxide. This vapor forms an explosive mixture(6.0 to 36.5% by volume) with air. Methyl alcohol is an important inexpensive raw material that is synthetically produced for the organic chemical industry. Nearly half of the methyl alcohol manufactured is used in the production of formaldehyde. Other uses of methyl alcohol are as an antifreeze and fuel for automobiles and as an intermediate in the production of synthetic protein.
6. Industrial solvent. Raw material for making formaldehyde and methyl esters of organic and inorganic acids. Antifreeze for automotive radiators and air brakes; ingredient of gasoline and diesel oil antifreezes. Octane booster in gasoline. As fuel for picnic stoves and soldering torches. Extractant for animal and vegetable oils. To denature ethanol. Softening agent for pyroxylin plastics. Solvent and solvent adjuvant for polymers. Solvent in the manufacture of cholesterol, streptomycin, vitamins, hormones, and other pharmaceuticals.
Methanol poisoning and First Aid Measures
Pathogenesis
First, methanol has a cumulative effect and is oxidized in the body into more toxic formaldehyde and formic acid. Methanol and its oxides directly damage the tissues, causing cerebral edema, meningeal hemorrhage, optic nerve and retinal atrophy, pulmonary congestion and edema, and hepatic and renal turbid swelling.
Second, methanol and its oxides cause blood circulation disorder, coenzyme system obstacles in vivo, resulting in lack of oxygen supply to the brain cortical cells, metabolic disorders, and related neurological and psychiatric symptoms.
Third, methanol oxidation products combine with the iron in the cytochrome oxidase, which inhibits the intracellular oxidation process thus causing metabolic disorders, acidosis along with organic acid accumulation in the body, and nerve cells impair.
Treatment
Keep away from the methanol dispersion area, excrete methanol from the body.
Antidote: Ethanol is an antidote to methanol poisoning. Ethanol can prevent methanol’s oxidation and promote its emission. Prepare 5% ethanol solution using 10% glucose solution, and drip slowly intravenously.
Maintain electrolyte balance: maintain respiratory and circulatory function, provide with a large number of Vitamin B.
Treatment of acidosis: Administrate timely sodium bicarbonate solution or sodium lactate solution based on blood gas analysis, carbon dioxide binding force measurement and clinical performance.
Prevent cerebral edemas actively, reduce intracranial pressure, improve fundus blood circulation, and prevent optic neuropathy if needed.
Inject intravenously cytochrome C, polar fluid to restore cytochrome oxidase function.
Control mental state by applying diazepam, perphenazine and the like.
Symptoms and treatments:
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Acute pain
morphine, pethidine
Convulsions
phenobarbital, amimystrine, diazepam
Coma
caffeine sodium benzoate
Respiratory failure
nikethamide, theophylline
Reactivities of Methanol
Methanol is the simplest aliphatic alcohol. It contains only one carbon atom. Unlike higher alcohols, it cannot form an olefin through dehydration. However, it can undergo other typical reactions of aliphatic alcohols involving cleavage of a C-H bond or O-H bond and displacement of the -OH group. Table 1 summarizes the reactions of methanol, which are classified in terms of their mechanisms. Examples of the reactions and products are given.
Homolytic dissociation energies of the C-O and O-H bonds in methanol are relatively high. Catalysts are often used to activate the bonds and to increase the selectivity to desired products.
Production
Methanol is prepared by pressure heating with carbon monoxide and hydrogen in the presence of a catalyst:
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If the conditions are strictly controlled, the yield can reach 100% and the purity can reach 99%.
Methane is mixed with oxygen (9:1, V/V) and methanol is obtained through a copper tube under heating and pressure:
Toxicity evaluation
Different sources of media describe the Toxicity evaluation of 67-56-1 differently. You can refer to the following data:
1. ADI is limited to GMP (FAO/WHO, 2001).
Toxic, can cause blindness.
LD50: 5628 mg/kg (rat, oral).
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Measurement
Date
System
Route/Organism
Dose
Effect
Skin and Eye Irritation
December 2016
?
eye /rabbit
40 mg
moderate
Skin and Eye Irritation
December 2016
?
eye /rabbit
100 mg/24H
moderate
Skin and Eye Irritation
December 2016
?
skin /rabbit
20 mg/24H
moderate
Mutation Data
December 2016
Cytogenetic Analysis
parenteral/grasshopper
3000 ppm
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Mutation Data
December 2016
Cytogenetic Analysis
oral/mouse
1 gm/kg
?
Mutation Data
December 2016
Cytogenetic Analysis
intraperitoneal/mouse
75 mg/kg
?
Mutation Data
December 2016
DNA Damage
oral/rat
10 μmol/kg
?
Mutation Data
December 2016
DNA inhibition
lymphocyte/human
300 mmol/L
?
Mutation Data
December 2016
DNA repair
/Escherichia coli
20 mg/well
?
Mutation Data
December 2016
morphological transform
fibroblast/mouse
0.01 mg/L/21D (-enzymatic activation step)
?
from The National Institute for Occupational Safety and Health - NIOSH
2. The toxic properties of methanol are the result of accumulation
of the formate intermediate in the blood and tissues of exposed
individuals. Formate accumulation produces metabolic
acidosis leading to the characteristic ocular toxicity (blindness)
observed in human methanol poisonings.
Humans and primates appear particularly sensitive to
methanol toxicity when compared to rats. This is attributed to
the slower rate of conversion in humans of the formate
metabolite via tetrahydrofolate. This step in methanol metabolism
occurs in rats at a rate ~2.5 times that observed in
humans.
Formate appears to directly affect the retina and optic nerve
by acting as a mitochondrial toxin. It is believed that formate
acts as a metabolic poison by inhibiting cytochrome oxidase
activity. The cells of the optic nerve have low reserves of cytochrome
oxidase and thus may be particularly sensitive to
formate-induced metabolic inhibition.
Methanol gasoline
Methanol gasoline refers to the M series mixture fuel made of addition of methanol to the gasoline and formulated using methanol fuel solvent. Among them, M15 (add 15% methanol in gasoline) clean methanol gasoline is used as vehicle fuel, respectively, used in a variety of gasoline engines. It can be applied to substitute the finished gasoline without changing the existing engine structure, and can also be mixed with refined oil. The methanol mixed fuel has excellent thermal efficiency, power, start-up and being economical. It is also characterized by lowering the emissions, saving oil and being safe and convenient. Methanol gasoline types of M35, M15, M20, M50, N85 and M100 with different blend ratios have been developed around the world according to the conditions of different countries. At present, the commercial methanol is mainly M85 (85% methanol + 15% gasoline) and M100 with M100 performance being better than M85 and having greater environmental advantages.
Description
Methyl alcohol, also known as methanol or wood alcohol, is a clear, colorless, flammable liquid
that is the simplest alcohol.World production of methanol is approximately 8.5 billion gallons annually. Methanol
is produced industrially, starting with the production of synthesis gas or syngas. Syngas used
in the production of methyl alcohol is a mixture of carbon monoxide and hydrogen formed
when natural gas reacts with steam or oxygen. Methyl alcohol is then synthesized
from carbon monoxide and hydrogen.Methyl alcohol is poisonous and is commonly used to denature ethyl alcohol. Methanol
poisoning results from ingestion, inhalation of methanol vapors, or absorption through
the skin. Methanol is transformed in the body to formaldehyde (H2CO) by the enzyme
alcohol dehydrogenase.The formaldehyde is then metabolized to formic acid (HCOOH)by aldehyde dehydrogenase.
Physical properties
Clear, colorless liquid with a characteristic alcoholic odor. Odor threshold concentrations ranged
from 8.5 ppbv (Nagata and Takeuchi, 1990) to 100.0 ppmv (Leonardos et al., 1969).
Experimentally determined detection and recognition odor threshold concentrations were 5.5
mg/m3 (4.2 ppmv) and 69 mg/m3 (53 ppmv), respectively (Hellman and Small, 1974).
History
It was first isolated in 1661 by the Irish chemist Robert Boyle
(1627–1691) who prepared it by the destructive distillation of boxwood, giving it the name
spirit of box, and the name wood alcohol is still used for methyl alcohol. Methyl alcohol is also
called pyroxylic spirit; pyroxylic is a general term meaning distilled from wood and indicates
that methyl alcohol is formed during pyrolysis of wood. The common name was derived in the
mid-1800s. The name methyl denotes the single carbon alkane methane in which a hydrogen
atom has been removed to give the methyl radical. The word alcohol is derived from Arabic
al kuhul.
Definition
ChEBI: Methanol is the primary alcohol that is the simplest aliphatic alcohol, comprising a methyl and an alcohol group. It has a role as an amphiprotic solvent, a fuel, a human metabolite, an Escherichia coli metabolite, a mouse metabolite and a Mycoplasma genitalium metabolite. It is an alkyl alcohol, a one-carbon compound, a volatile organic compound and a primary alcohol. It is a conjugate acid of a methoxide.
Production Methods
Modern industrial-scale methanol production is exclusively
based on synthesis from pressurized mixtures of hydrogen,
carbon monoxide, and carbon dioxide gases in the presence
of catalysts. Based on production volume, methanol has
become one of the largest commodity chemicals produced
in the world.
Reactions
Methyl alcohol is a versatile material, reacting (1) with sodium metal, forming sodium methylate, sodium methoxide CH3ONa plus hydrogen gas, (2) with phosphorus chloride, bromide, iodide, forming methyl chloride, bromide, iodide, respectively, (3) with H2SO4 concentrated, forming dimethyl ether (CH3)2O, (4) with organic acids, warmed in the presence of H2SO4, forming esters, e.g., methyl acetate CH3COOCH3, [CAS: 79-20-9], methyl salicylate C6H4(OH)·COOCH3, possessing characteristic odors, (5) with magnesium methyl iodide in anhydrous ether (Grignard’s solution), forming methane as in the case of primary alcohols, (6) with calcium chloride, forming a solid addition compound 4CH3OH·CaCl2, which is decomposed by H2O, (7) with oxygen, in the presence of heated smooth copper or silver forming formaldehyde. The density of pure methyl alcohol is 0.792 at 20 °C compared with H2O at 4 °C (the corresponding figure for ethyl alcohol is 0.789), and the percentage of methyl alcohol present in a methyl alcohol-water solution may be determined from the density of the sample.
World Health Organization (WHO)
Methanol has been subjected to abuse by consumption as a
substitute for ethanol. Its toxic metabolites cause irreversible blindness and severe
metabolic acidosis, and are ultimately fatal. Methanol continues to be used as an
industrial solvent.
General Description
A colorless fairly volatile liquid with a faintly sweet pungent odor like that of ethyl alcohol. Completely mixes with water. The vapors are slightly heavier than air and may travel some distance to a source of ignition and flash back. Any accumulation of vapors in confined spaces, such as buildings or sewers, may explode if ignited. Used to make chemicals, to remove water from automotive and aviation fuels, as a solvent for paints and plastics, and as an ingredient in a wide variety of products.
Reactivity Profile
Methanol reacts violently with acetyl bromide [Merck 11th ed. 1989]. Mixtures with concentrated sulfuric acid and concentrated hydrogen peroxide can cause explosions. Reacts with hypochlorous acid either in water solution or mixed water/carbon tetrachloride solution to give methyl hypochlorite, which decomposes in the cold and may explode on exposure to sunlight or heat. Gives the same product with chlorine. Can react explosively with isocyanates under basic conditions. The presence of an inert solvent mitigates this reaction [Wischmeyer 1969]. A violent exothermic reaction occurred between methyl alcohol and bromine in a mixing cylinder [MCA Case History 1863. 1972]. A flask of anhydrous lead perchlorate dissolved in Methanol exploded when Methanol was disturbed [J. Am. Chem. Soc. 52:2391. 1930]. P4O6 reacts violently with Methanol. (Thorpe, T. E. et al., J. Chem. Soc., 1890, 57, 569-573). Ethanol or Methanol can ignite on contact with a platinum-black catalyst. (Urben 1794).
Hazard
Flammable, dangerous fire risk. Explosive
limits in air 6–36.5% by volume. Toxic by ingestion
(causes blindness). Headache, eye damage, dizziness, and nausea.
Health Hazard
Different sources of media describe the Health Hazard of 67-56-1 differently. You can refer to the following data:
1. Ingestion of adulterated alcoholic beveragescontaining methanol has resulted in innumerable loss of human lives throughout theworld. It is highly toxic, causing acidosis andblindness. The symptoms of poisoning arenausea, abdominal pain, headache, blurredvision, shortness of breath, and dizziness.In the body, methanol oxidizes to formaldehyde and formic acid — the latter could bedetected in the urine, the pH of which is lowered (when poisoning is severe).The toxicity of methanol is attributed tothe metabolic products above. Ingestion inlarge amounts affects the brain, lungs, gastrointestinal tract, eyes, and respiratory system and can cause coma, blindness, anddeath. The lethal dose is reported to be60–250 mL. The poisoning effect is prolonged and the recovery is slow, often causing permanent loss of sight.Other exposure routes are inhalation andskin absorption. Exposure to methanol vaporto at 2000 ppm at regular intervals over aperiod of 4 weeks caused upper respiratorytract irritation and mucoid nasal discharge inrats. Such discharge was found to be a doserelated effect.Inhalation in humans may produce headache, drowsiness, and eye irritation. Prolonged skin contact may cause dermatitis andscaling. Eye contact can cause burns anddamage vision..
2. The acute toxicity of methanol by ingestion, inhalation, and skin contact is low. Ingestion
of methanol or inhalation of high concentrations can produce headache, drowsiness,
blurred vision, nausea, vomiting, blindness, and death. In humans, 60 to 250 mL is
reported to be a lethal dose. Prolonged or repeated skin contact can cause irritation and
inflammation; methanol can be absorbed through the skin in toxic amounts. Contact of
methanol with the eyes can cause irritation and burns. Methanol is not considered to have
adequate warning properties.
Methanol has not been found to be carcinogenic in humans. Information available is
insufficient to characterize the reproductive hazard presented by methanol. In animal
tests, the compound produced developmental effects only at levels that were maternally
toxic; hence, it is not considered to be a highly significant hazard to the fetus. Tests in
bacterial or mammalian cell cultures demonstrate no mutagenic activity
Flammability and Explosibility
Methanol is a flammable liquid (NFPA rating = 3) that burns with an invisible flame
in daylight; its vapor can travel a considerable distance to an ignition source and
"flash back." Methanol-water mixtures will burn unless very dilute. Carbon dioxide
or dry chemical extinguishers should be used for methanol 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.
Safety Profile
A human poison by
ingestion. Poison experimentally by skin
contact. Moderately toxic experimentally by
intravenous and intraperitoneal routes.
Mildly toxic by inhalation. Human systemic
effects: changes in circulation, cough,
dyspnea, headache, lachrymation, nausea or
vomiting, optic nerve neuropathy,
respiratory effects, visual field changes. An
experimental teratogen. Experimental
reproductive effects. An eye and skin
irritant. Human mutation data reported. A
narcotic.
Its main toxic effect is exerted upon the
nervous system, particularly the optic nerves
and possibly the retinae. The condtion can
progress to permanent blindness. Once
absorbed, methanol is only very slowly
eliminated. Coma resulting from massive
exposures may last as long as 2-4 days. In
the body, the products formed by its
oxidation are formaldehyde and formic acid,
both of which are toxic. Because of the slow
elimination, methanol should be regarded as
a cumulative poison. Though single
exposures to fumes may cause no harmful
effect, daily exposure may result in the
accumulation of sufficient methanol in the
body to cause illness. Death from ingestion of less than 30 mL has been reported. A
common air contaminant.
Flammable liquid. Dangerous fire hazard
when exposed to heat, flame, or oxidlzers.
Explosive in the form of vapor when
exposed to heat or flame. Explosive reaction
with chloroform + sodium methoxide,
diethyl zinc. Violent reaction with alkyl
aluminum salts, acetyl bromide, chloroform
+ sodlum hydroxide, CrO3, cyanuric
chloride, (I + ethanol + HgO), Pb(ClO4)2,
HClO4, P2O3, (KOH + CHCb), nitric acid.
Incompatible with berylhum dihydride,
metals (e.g., potassium, magnesium),
oxidants (e.g., barium perchlorate, bromine,
sodium hypochlorite, chlorine, hydrogen
peroxide), potassium tert-butoxide, carbon
tetrachloride + metals (e.g., aluminum,
magnesium, zinc), dlchloromethane.
Dangerous; can react vigorously with
oxidizing materials. To fight fire, use alcohol
foam. When heated to decomposition it
emits acrid smoke and irritating fumes.
Source
Methanol occurs naturally in small-flowered oregano (5 to 45 ppm) (Baser et al., 1991),
Guveyoto shoots (700 ppb) (Baser et al., 1992), orange juice (0.8 to 80 ppm), onion bulbs,
pineapples, black currant, spearmint, apples, jimsonweed leaves, soybean plants, wild parsnip,
blackwood, soursop, cauliflower, caraway, petitgrain, bay leaves, tomatoes, parsley leaves, and
geraniums (Duke, 1992).
Methanol may enter the environment from methanol spills because it is used in formaldehyde
solutions to prevent polymerization (Worthing and Hance, 1991).
Environmental fate
Biological. In a 5-d experiment, [14C]methanol applied to soil water suspensions under aerobic
and anaerobic conditions gave 14CO2 yields of 53.4 and 46.3%, respectively (Scheunert et al.,
1987). Heukelekian and Rand (1955) reported a 5-d BOD value of 0.85 g/g which is 56.7% of the
ThOD value of 1.50 g/g. Using the BOD technique to measure biodegradation, the mean 5-d BOD
value (mM BOD/mM methanol) and ThOD were 0.93 and 62.0%, respectively (Vaishnav et al.,
1987).
Photolytic. Photooxidation of methanol in an oxygen-rich atmosphere (20%) in the presence of
chlorine atoms yielded formaldehyde and hydroxyperoxyl radicals. The reaction is initiated via
hydrogen abstraction by OH radicals or chlorine atoms yielding a hydroxymethyl radical.
Chlorine, formaldehyde, carbon monoxide, hydrogen peroxide, and formic acid were detected
(Whitbeck, 1983). Reported rate constants for the reaction of methanol and OH radicals in the
atmosphere: 5.7 x 10-11 cm3/mol·sec at 300 K (Hendry and Kenley, 1979), 5.7 x 10-8 L/mol·sec
(second-order) at 292 K (Campbell et al., 1976), 1.00 x 10-12 cm3/molecule·sec at 292 K (Meier et
al., 1985), 7.6 x 10-13 cm3/molecule·sec at 298 K (Ravishankara and Davis, 1978), 6.61 x 10-13
cm3/molecule·sec at room temperature (Wallington et al., 1988a). Based on an atmospheric OH
concentration of 1.0 x 106 molecule/cm3, the reported half-life of methanol is 8.6 d (Grosjean,
1997).
Chemical/Physical. In a smog chamber, methanol reacted with nitrogen dioxide to give methyl
nitrite and nitric acid (Takagi et al., 1986). The formation of these products was facilitated when
this experiment was accompanied by UV light (Akimoto and Takagi, 1986).
Methanol will not hydrolyze because it does not have a hydrolyzable functional group (Kollig,
1993).
At an influent concentration of 1,000 mg/L, treatment with GAC resulted in an effluent
concentration of 964 mg/L. The adsorbability of the carbon used was 7 mg/g carbon (Guisti et al.,
1974).
Hydroxyl radicals react with methanol in aqueous solution at a reaction rate of 1.60 x 10-12
cm3/molecule?sec (Wallington et al., 1988).
Complete combustion in air produces carbon dioxide and water. The stoichiometric equation for
this oxidation reaction is:
2CH4O + 3O2 → 2CO2 + 4H2O
storage
Methanol should
be used only in areas free of ignition sources, and quantities greater than 1 liter
should be stored in tightly sealed metal containers in areas separate from oxidizers.
Shipping
UN1230 Methanol, Hazard Class: 3; Labels:
3-Flammable liquid, 6.1-Poisonous material. (International)
Purification Methods
Almost all methanol is now obtained synthetically. Likely impurities are water, acetone, formaldehyde, ethanol, methyl formate and traces of dimethyl ether, methylal, methyl acetate, acetaldehyde, carbon dioxide and ammonia. Most of the water (down to about 0.01%) can be removed by fractional distillation. Drying with CaO is unnecessary and wasteful. Anhydrous methanol can be obtained from "absolute" material by passage through Linde type 4A molecular sieves, or by drying with CaH2, CaSO4, or with just a little more sodium than required to react with the water present, in all cases the methanol is then distilled. Two treatments with sodium reduces the water content to about 5 x 10-5%. [Friedman et al. J Am Chem Soc 83 4050 1961.] Lund and Bjerrum [Chem Ber 64 210 1931] warmed clean dry magnesium turnings (5g) and iodine (0.5g) with 50-75mL of "absolute" methanol in a flask until the iodine disappeared and all the magnesium was converted to the methoxide. Up to 1L of methanol was added and, after refluxing for 2-3hours, it was distilled off, excluding moisture from the system. Redistillation from tribromobenzoic acid removes basic impurities and traces of magnesium oxides, and leaves conductivity-quality material. The method of Hartley and Raikes [J Chem Soc 127 524 1925] gives a slightly better product. This consists of an initial fractional distillation, followed by distillation from aluminium methoxide, and then ammonia and other volatile impurities are removed by refluxing for 6hours with freshly dehydrated CuSO4 (2g/L) while dry air is passed through: the methanol is finally distilled. (The aluminium methoxide is prepared by warming with aluminium amalgam (3g/L) until all the aluminium has reacted. The amalgam is obtained by warming pieces of sheet aluminium with a solution of HgCl2 in dry methanol.) This treatment also removes aldehydes. If acetone is present in the methanol, it is usually removed prior to drying. Bates, Mullaly and Hartley [J Chem Soc 401 1923] dissolved 25g of iodine in 1L of methanol and then poured the solution, with constant stirring, into 500mL of M NaOH. Addition of 150mL of water precipitated iodoform. The solution was allowed to stand overnight, filtered, then boiled under reflux until the odour of iodoform disappeared, and fractionally distilled. (This treatment also removes formaldehyde.) Morton and Mark [Ind Eng Chem (Anal Edn) 6 151 1934] refluxed methanol (1L) with furfural (50mL) and 10% NaOH solution (120mL) for 6-12hours, the refluxing resin carries down with it the acetone and other carbonyl-containing impurities. The alcohol was then fractionally distilled. Evers and Knox [J Am Chem Soc 73 1739 1951], after refluxing 4.5L of methanol for 24hours with 50g of magnesium, distilled off 4L of it, which they then refluxed with AgNO3 for 24hours in the absence of moisture or CO2. The methanol was again distilled, shaken for 24hours with activated alumina before being filtered through a glass sinter and distilled under nitrogen in an all-glass still. Material suitable for conductivity work was obtained. Variations of the above methods have also been used. For example, a sodium hydroxide solution containing iodine has been added to methanol and, after standing for 1day, the solution has been poured slowly into about a quarter of its volume of 10% AgNO3, shaken for several hours, then distilled. Sulfanilic acid has been used instead of tribromobenzoic acid in Lund and Bjerrum's method. A solution of 15g of magnesium in 500mL of methanol has been heated under reflux, under nitrogen, with hydroquinone (30g), before degassing and distilling the methanol, which was subsequently stored with magnesium (2g) and hydroquinone (4g per 100mL). Refluxing for about 12hours removes the bulk of the formaldehyde from methanol: further purification has been obtained by subsequent distillation, refluxing for 12hours with dinitrophenylhydrazine (5g) and H2SO4 (2g/L), and again fractionally distilling. [Beilstein 1 IV 1227.]
Incompatibilities
Methanol reacts violently with strong
oxidizers, causing a fire and explosion hazard.
Waste Disposal
Consult with environmental
regulatory agencies for guidance on acceptable disposal
practices. Generators of waste containing this contaminant
(≥100 kg/mo) must conform to EPA regulations governing
storage, transportation, treatment, and waste disposal.
Incineration
Check Digit Verification of cas no
The CAS Registry Mumber 67-56-1 includes 5 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 2 digits, 6 and 7 respectively; the second part has 2 digits, 5 and 6 respectively.
Calculate Digit Verification of CAS Registry Number 67-56:
(4*6)+(3*7)+(2*5)+(1*6)=61
61 % 10 = 1
So 67-56-1 is a valid CAS Registry Number.
InChI:InChI=1/CH4O.H2O/c1-2;/h2H,1H3;1H2
67-56-1Relevant articles and documents
C-C Bond Cleavage of Acetonitrile by a Dinuclear Copper(II) Cryptate
Lu, Tongbu,Zhuang, Xiaomei,Li, Yanwu,Chen, Shi
, p. 4760 - 4761 (2004)
The dinuclear copper(II) cryptate [Cu2L](ClO4)4 (1) cleaves the C?C bond of acetonitrile at room temperature to produce a cyanide bridged complex of [Cu2L(CN)](ClO4)3·2CH3CN·4H2O (2). The cleavage mechanism is presented on the basis of the results of the crystal structure of 2, electronic absorption spectra, ESI-MS spectroscopy, and GC spectra of 1, respectively. Copyright
Photochemical and enzymatic synthesis of methanol from HCO3 - with dehydrogenases and zinc porphyrin
Amao, Yutaka,Watanabe, Tomoe
, p. 1544 - 1545 (2004)
Photochemical and enzymatic methanol synthesis from HCO3 - with formate dehydrogenase (FDH), aldehyde dehydrogenase (AldDH), and alcohol dehydrogenase (ADH) via the photoreduction of MV2+ using ZnTPPS photosensitization wa
Catalytic Activity of Nanosized CuO-ZnO Supported on Titanium Chips in Hydrogenation of Carbon Dioxide to Methyl Alcohol
Ahn, Ho-Geun,Lee, Hwan-Gyu,Chung, Min-Chul,Park, Kwon-Pil,Kim, Ki-Joong,Kang, Byeong-Mo,Jeong, Woon-Jo,Jung, Sang-Chul,Lee, Do-Jin
, p. 2024 - 2027 (2016)
In this study, titanium chips (TC) generated from industrial facilities was utilized as TiO2 support for hydrogenation of carbon dioxide (CO2) to methyl alcohol (CH3OH) over Cu-based catalysts. Nanosized CuO and ZnO catalysts were deposited on TiO2 support using a co-precipitation (CP) method (CuO-ZnO/TiO2), where the thermal treatment of TC and the particle size of TiO2 are optimized on CO2 conversion under different reaction temperature and contact time. Direct hydrogenation of CO2 to CH3OH over CuO-ZnO/TiO2 catalysts was achieved and the maximum selectivity (22%) and yield (18.2%) of CH3OH were obtained in the range of reaction temperature 210~240 °C under the 30 bar. The selectivity was readily increased by increasing the flow rate, which does not affect much to the CO2 conversion and CH3OH yield.
Comparative Study of Diverse Copper Zeolites for the Conversion of Methane into Methanol
Park, Min Bum,Ahn, Sang Hyun,Mansouri, Ali,Ranocchiari, Marco,van Bokhoven, Jeroen A.
, p. 3705 - 3713 (2017)
The characterization and reactive properties of copper zeolites with twelve framework topologies (MOR, EON, MAZ, MEI, BPH, FAU, LTL, MFI, HEU, FER, SZR, and CHA) are compared in the stepwise partial oxidation of methane into methanol. Cu2+ ion-exchanged zeolite omega, a MAZ-type material, reveals the highest yield (86 μmol g(cat.)?1) among these materials after high-temperature activation and liquid methanol extraction. The high yield is ascribed to the relatively high density of copper–oxo active species, which form in its three-dimensional 8-membered (MB) ring channels. In situ UV/Vis studies show that diverse copper species form in different zeolites after high-temperature activation, suggesting that there are no universally active species. Nonetheless, there are some dominant factors required for achieving high methanol yields: 1) highly dispersed copper–oxo species; 2) large amount of exchanged copper in small-pore zeolites; 3) moderately high temperature of activation; and 4) use of proton form zeolite precursors. Cu-omega and Cu-mordenite, with the proton form of mordenite as the precursor, yield methanol after activation in oxygen and reaction with methane at only 200 °C, that is, under isothermal conditions.
Spontaneous hydrolysis of ionized phosphate monoesters and diesters and the proficiencies of phosphatases and phosphodiesterases as catalysts
Wolfenden, Richard,Ridgway, Caroline,Young, Gregory
, p. 833 - 834 (1998)
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Facile synthesis of ZnO particles: Via benzene-assisted co-solvothermal method with different alcohols and its application
Maneechakr, Panya,Karnjanakom, Surachai,Samerjit, Jittima
, p. 73947 - 73952 (2016)
In this study, ZnO particles with different morphologies were synthesized by a novel co-solvothermal method using benzene. The prepared samples were characterized by Brunauer-Emmett-Teller (BET) measurements, X-ray diffractometry (XRD), scanning electron microscopy coupled with an energy dispersive X-ray detector (SEM-EDX), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectrometry (XPS), and H2-temperature programmed reduction (H2-TPR). The results showed that the molecular sizes and carbon numbers of the alcohols used in the reaction and the addition of benzene had a great effect on the morphologies, textural properties, and crystalline structures of the material products in our reaction system. Different ZnO morphologies, such as spherical coral-like, carnation-like, rose-like, and plate-like structures, were obtained using methanol, ethanol, propanol, and butanol, respectively. Moreover, Cu particles loaded on ZnO with different morphologies were also investigated for the hydrogenation of CO2 to CH3OH. High catalytic activity and selectivity (82.8%) for CH3OH formation were obtained using ZnO prepared from methanol with Cu doping (Cu/ZnO-Me).
Efficient ionic liquid-based platform for multi-enzymatic conversion of carbon dioxide to methanol
Zhang, Zhibo,Muschiol, Jan,Huang, Yuhong,Sigurdardóttir, Sigyn Bj?rk,Von Solms, Nicolas,Daugaard, Anders E.,Wei, Jiang,Luo, Jianquan,Xu, Bao-Hua,Zhang, Suojiang,Pinelo, Manuel
, p. 4339 - 4348 (2018)
Low yields commonly obtained during enzymatic conversion of CO2 to methanol are attributed to low CO2 solubility in water. In this study, four selected ionic liquids with high CO2 solubility were separately added to the multi-enzyme reaction mixture and the yields were compared to the pure aqueous system (control). In an aqueous 20% [CH][Glu] system, yield increased ca. 3.5-fold compared to the control (ca. 5-fold if NADH regeneration was incorporated). Molecular dynamics simulation revealed that CO2 remains for longer in a productive conformation in the enzyme in the presence of [CH][Glu], which explains the marked increase of yield that was also confirmed by isothermal titration calorimetry-lower energy (ΔG) binding of CO2 to FDH. The results suggest that the accessibility of CO2 to the enzyme active site depends on the absence/presence and nature of the ionic liquid, and that the enzyme conformation determines CO2 retention and hence final conversion.
Comparative study of hydrotalcite-derived supported Pd2Ga and PdZn intermetallic nanoparticles as methanol synthesis and methanol steam reforming catalysts
Ota, Antje,Kunkes, Edward L.,Kasatkin, Igor,Groppo, Elena,Ferri, Davide,Poceiro, Beatriz,Navarro Yerga, Rufino M.,Behrens, Malte
, p. 27 - 38 (2012)
An effective and versatile synthetic approach to produce well-dispersed supported intermetallic nanoparticles is presented that allows a comparative study of the catalytic properties of different intermetallic phases while minimizing the influence of differences in preparation history. Supported PdZn, Pd2Ga, and Pd catalysts were synthesized by reductive decomposition of ternary Hydrotalcite-like compounds obtained by co-precipitation from aqueous solutions. The precursors and resulting catalysts were characterized by HRTEM, XRD, XAS, and CO-IR spectroscopy. The Pd2+ cations were found to be at least partially incorporated into the cationic slabs of the precursor. Full incorporation was confirmed for the PdZnAl-Hydrotalcite-like precursor. After reduction of Ga- and Zn-containing precursors, the intermetallic compounds Pd2Ga and PdZn were present in the form of nanoparticles with an average diameter of 6 nm or less. Tests of catalytic performance in methanol steam reforming and methanol synthesis from CO2 have shown that the presence of Zn and Ga improves the selectivity to CO2 and methanol, respectively. The catalysts containing intermetallic compounds were 100 and 200 times, respectively, more active for methanol synthesis than the monometallic Pd catalyst. The beneficial effect of Ga in the active phase was found to be more pronounced in methanol synthesis compared with steam reforming of methanol, which is likely related to insufficient stability of the reduced Ga species in the more oxidizing feed of the latter reaction. Although the intermetallic catalysts were in general less active than a Cu-/ZnO-based material prepared by a similar procedure, the marked changes in Pd reactivity upon formation of intermetallic compounds and to study the tunability of Pd-based catalysts for different reactions.
Self-sufficient and exclusive oxygenation of methane and its source materials with oxygen to methanol via metgas using oxidative bi-reforming
Olah, George A.,Prakash, G. K. Surya,Goeppert, Alain,Czaun, Miklos,Mathew, Thomas
, p. 10030 - 10031 (2013)
A combination of complete methane combustion with oxygen of the air coupled with bi-reforming leads to the production of metgas (H2/CO in 2:1 mole ratio) for exclusive methanol synthesis. The newly developed oxidative bi-reforming allows direct oxygenation of methane to methanol in an overall economic and energetically efficient process, leaving very little, if any, carbon footprint or byproducts.
Spinel-Structured ZnCr2O4 with Excess Zn Is the Active ZnO/Cr2O3 Catalyst for High-Temperature Methanol Synthesis
Song, Huiqing,Laudenschleger, Daniel,Carey, John J.,Ruland, Holger,Nolan, Michael,Muhler, Martin
, p. 7610 - 7622 (2017)
A series of ZnO/Cr2O3 catalysts with different Zn:Cr ratios was prepared by coprecipitation at a constant pH of 7 and applied in methanol synthesis at 260-300 °C and 60 bar. The X-ray diffraction (XRD) results showed that the calcined catalysts with ratios from 65:35 to 55:45 consist of ZnCr2O4 spinel with a low degree of crystallinity. For catalysts with Zn:Cr ratios smaller than 1, the formation of chromates was observed in agreement with temperature-programmed reduction results. Raman and XRD results did not provide evidence for the presence of segregated ZnO, indicating the existence of Zn-rich nonstoichiometric Zn-Cr spinel in the calcined catalyst. The catalyst with Zn:Cr = 65:35 exhibits the best performance in methanol synthesis. The Zn:Cr ratio of this catalyst corresponds to that of the Zn4Cr2(OH)12CO3 precursor with hydrotalcite-like structure obtained by coprecipitation, which is converted during calcination into a nonstoichiometric Zn-Cr spinel with an optimum amount of oxygen vacancies resulting in high activity in methanol synthesis. Density functional theory calculations are used to examine the formation of oxygen vacancies and to measure the reducibility of the methanol synthesis catalysts. Doping Cr into bulk and the (10-10) surface of ZnO does not enhance the reducibility of ZnO, confirming that Cr:ZnO cannot be the active phase. The (100) surface of the ZnCr2O4 spinel has a favorable oxygen vacancy formation energy of 1.58 eV. Doping this surface with excess Zn charge-balanced by oxygen vacancies to give a 60% Zn content yields a catalyst composed of an amorphous ZnO layer supported on the spinel with high reducibility, confirming this as the active phase for the methanol synthesis catalyst.
A novel low-temperature methanol synthesis method from CO/H2/CO2 based on the synergistic effect between solid catalyst and homogeneous catalyst
Zhao, Tian-Sheng,Zhang, Kun,Chen, Xuri,Ma, Qingxiang,Tsubaki, Noritatsu
, p. 98 - 104 (2010)
The activity of a binary catalyst in alcoholic solvents for methanol synthesis from CO/H2/CO2 at low temperature was investigated in a concurrent synthesis course. Experiment results showed that the combination of homogeneous potassium formate catalyst and solid copper-magnesia catalyst enhanced the conversion of CO2-containing syngas to methanol at temperature of 423-443 K and pressure of 3-5 MPa. Under a contact time of 100 g h/mol, the maximum conversion of total carbon approached the reaction equilibrium and the selectivity of methanol was 99%. A reaction pathway involving esterification and hydrogenolysis of esters was postulated based on the integrative and separate activity tests, along with the structural characterization of the catalysts. Both potassium formate for the esterification as well as Cu/MgO for the hydrogenolysis were found to be crucial to this homogeneous and heterogeneous synergistically catalytic system. CO and H2 were involved in the recycling of potassium formate.
Continuous supercritical low-temperature methanol synthesis with n-butane as a supercritical fluid
Reubroycharoen, Prasert,Bao, Jun,Zhang, Yi,Tsubaki, Noritatsu
, p. 790 - 791 (2008)
A process of supercritical low-temperature methanol synthesis from syngas containing CO2 was carried out at 443 K and 60 bar. The 2-butanol and n-butane was used as catalytic solvent and supercritical medium, respectively. The results showed that the total carbon conversion, especially the CO 2 conversion of the methanol synthesis was increased significantly under the supercritical condition. Copyright
Molybdenum-Bismuth Bimetallic Chalcogenide Nanosheets for Highly Efficient Electrocatalytic Reduction of Carbon Dioxide to Methanol
Sun, Xiaofu,Zhu, Qinggong,Kang, Xinchen,Liu, Huizhen,Qian, Qingli,Zhang, Zhaofu,Han, Buxing
, p. 6771 - 6775 (2016)
Methanol is a very useful platform molecule and liquid fuel. Electrocatalytic reduction of CO2 to methanol is a promising route, which currently suffers from low efficiency and poor selectivity. Herein we report the first work to use a Mo-Bi bimetallic chalcogenide (BMC) as an electrocatalyst for CO2 reduction. By using the Mo-Bi BMC on carbon paper as the electrode and 1-butyl-3-methylimidazolium tetrafluoroborate in MeCN as the electrolyte, the Faradaic efficiency of methanol could reach 71.2 % with a current density of 12.1 mA cm-2, which is much higher than the best result reported to date. The superior performance of the electrode resulted from the excellent synergistic effect of Mo and Bi for producing methanol. The reaction mechanism was proposed and the reason for the synergistic effect of Mo and Bi was discussed on the basis of some control experiments. This work opens a way to produce methanol efficiently by electrochemical reduction of CO2.
Characterization of modified Fischer-Tropsch catalysts promoted with alkaline metals for higher alcohol synthesis
Cosultchi, Ana,Perez-Luna, Miguel,Morales-Serna, Jose Antonio,Salmon, Manuel
, p. 368 - 377 (2012)
Two series of Cu/Co/Cr modified Fischer-Tropsch catalyst promoted with Zn or Mn and an alkaline metal (Me: Li, Na, K, Rb, Cs) were prepared by co-precipitation method and tested for high alcohol synthesis (HAS) at one hour on-stream and at two temperatures, 300 and 350 °C. The results indicate that the best selectivity toward high alcohols depends on temperature and catalysts composition and is obtained as follows: a) at 300 °C over catalysts without Zn and containing K, Na and Rb; b) at 350 °C over catalysts without Zn and containing K; c) at 350 °C over catalysts containing Zn as well as Li and Cs.
ACID-CATALYZED HYDROLYSIS OF 2-METHOXYPROPENAL
Fedoronko, Michal,Petrusova, Maria,Tvaroska, Igor
, p. 85 - 94 (1983)
2-Methoxypropenal in acid media undergoes general acid-catalyzed hydrolysis with formation of 2-oxopropanal.The kinetics of this reaction were studied, the rate constants established, and a reaction mechanism is suggested.Hydrolysis of 2-methoxypropenal is governed by a mechanism of the vinyl ether type, and the presence of the aldehyde group causes a decrease in the reaction rate.The analogy of the acid-catalyzed hydrolysis of 2-methoxypropenal to that of a vinyl ether was shown by the solvent isotope-effect, kD/kH=0.41, and the value of the Broensted exponent, α=0.60.The activation parameters found and quantum-chemical calculations of charge distribution in 2-methoxypropenal and other model compounds were also utilized to explain the mechanism of the acid-catalyzed hydrolysis of the title compound.
Carbon Dioxide Conversion to Methanol over Size-Selected Cu4 Clusters at Low Pressures
Liu, Cong,Yang, Bing,Tyo, Eric,Seifert, Soenke,Debartolo, Janae,Von Issendorff, Bernd,Zapol, Peter,Vajda, Stefan,Curtiss, Larry A.
, p. 8676 - 8679 (2015)
The activation of CO2 and its hydrogenation to methanol are of much interest as a way to utilize captured CO2. Here, we investigate the use of size-selected Cu4 clusters supported on Al2O3 thin films for CO2 reduction in the presence of hydrogen. The catalytic activity was measured under near-atmospheric reaction conditions with a low CO2 partial pressure, and the oxidation state of the clusters was investigated by in situ grazing incidence X-ray absorption spectroscopy. The results indicate that size-selected Cu4 clusters are the most active low-pressure catalyst for catalytic CO2 conversion to CH3OH. Density functional theory calculations reveal that Cu4 clusters have a low activation barrier for conversion of CO2 to CH3OH. This study suggests that small Cu clusters may be excellent and efficient catalysts for the recycling of released CO2.
Selective Photoreduction of Carbon Dioxide to Methanol on Titanium Dioxide Photocatalysts in Propylene Carbonate Solution
Kuwabata, Susumu,Uchida, Hiroyuki,Ogawa, Akihiro,Hirao, Shigeki,Yoneyama, Hiroshi
, p. 829 - 830 (1995)
Methanol is selectively photosynthesised from carbon dioxide using TiO2 photocatalysts in propylene carbonate containing propan-2-ol as a hole scavenger.
Effect of Γ-alumina nanorods on CO hydrogenation to higher alcohols over lithium-promoted CuZn-based catalysts
Choi, SuMin,Kang, YoungJong,Kim, SangWoo
, p. 188 - 196 (2018)
To achieve high catalytic activities and long-term stability to produce higher alcohols via CO hydrogenation, the catalytic activities were tuned by controlling the loading amounts of γ-alumina nanorods and Al3+ ions added to modify Cu-Zn catalysts promoted with Li. The selectivity of higher alcohols and the CO conversion to higher alcohols over a Li-modified Cu0.45Zn0.45Al0.1 catalyst supported on 10% nanorods were 1.8 and 2.7 times higher than those with a Cu-Zn catalyst without nanorods and Al3+ ions, respectively. The introduction of the thermally and chemically stable γ-Al2O3 nanorod support and of Al3+ to the modified catalysts improves the catalytic activities by decreasing the crystalline size of CuO and increasing the total basicity. Along with the nanorods, a refractory CuAl2O4 formed by the thermal reaction of CuO and Al3+ enhances the long-term stability by increasing the resistance to sintering of the catalyst.
CO2 Conversion into Methanol Using Granular Silicon Carbide (α6H-SiC): A Comparative Evaluation of 355 nm Laser and Xenon Mercury Broad Band Radiation Sources
Gondal, Mohammed Ashraf,Ali, Mohammed Ashraf,Dastageer, Mohamed Abdulkader,Chang, Xiaofeng
, p. 108 - 117 (2013)
Granular silicon carbide (α6H-SiC) was investigated as a photo-reduction catalyst for CO2 conversion into methanol using a 355 nm laser from the third harmonic of pulsed Nd:YAG laser and 500 W collimated xenon mercury (XeHg) broad band lamp. The reaction cell was filled with distilled water, α6H-SiC granules and pressurized with CO2 gas at 50 psi. Maximum molar concentration of methanol achieved was 1.25 and 0.375 mmol/l and the photonic efficiencies of CO2 conversion into methanol achieved were 1.95 and 1.16 % using the laser and the XeHg lamp respectively. The selectivity of methanol produced using the laser irradiation was 100 % as compared to about 50 % with the XeHg lamp irradiation. The band gap energy of silicon carbide was estimated to be 3.17 eV and XRD demonstrated that it is a highly crystalline material. This study demonstrated that commercially available granular silicon carbide is a promising photo-reduction catalyst for CO 2 into methanol. Graphical Abstract: Gas Chromatograms of reaction products collected at 30-120 min irradiation in the presence of 355 nm laser having 40 mJ/pulse energy. The inset shows the comparison of retention time of GC peaks with the methanol standard and it is at 2.46 min.[Figure not available: see fulltext.]
Continuous precipitation of Cu/ZnO/Al2O3 catalysts for methanol synthesis in microstructured reactors with alternative precipitating agents
Simson, Georg,Prasetyo, Eko,Reiner, Stefanie,Hinrichsen, Olaf
, p. 1 - 12 (2013)
Ternary Cu/ZnO/Al2O3 catalyst systems were systematically prepared by innovative synthesis routes in microstructured synthesis setups, allowing to study different types of micromixers. The coprecipitation in the slit plate and valve-assisted mixers was operated continuously under exact control of pH, temperature, concentration and ageing time. Due to the enhanced surface to volume ratio in microstructured reactors, a precise temperature control and efficient mixing of the reactants are enabled. The precipitation was performed with sodium, ammonium and potassium carbonate as well as sodium hydroxide. To evaluate the potential of the novel synthesis routes, reference samples in a conventional batch process were prepared. The catalysts were synthesized according to the constant pH method with a molar ratio of 60:30:10 for copper, zinc and aluminum. The synthesis routes applied have a significant influence on the structures of hydroxycarbonate precursors and on the catalytic activity in methanol synthesis. XRD patterns of hydroxycarbonate precursors from the synthesis in micromixers, especially using ammonium carbonate as precipitating agent, display high crystallinity and sharp reflections of malachite and rosasite. Cu/ZnO/Al2O3 catalysts prepared in continuously operated micromixers in general show higher specific copper surface areas than catalysts prepared in conventional batch processes. The highest methanol productivity of all prepared catalyst systems was observed with the catalyst precipitated in the slit plate mixer with ammonium carbonate.
Stable amorphous georgeite as a precursor to a high-activity catalyst
Kondrat, Simon A.,Smith, Paul J.,Wells, Peter P.,Chater, Philip A.,Carter, James H.,Morgan, David J.,Fiordaliso, Elisabetta M.,Wagner, Jakob B.,Davies, Thomas E.,Lu, Li,Bartley, Jonathan K.,Taylor, Stuart H.,Spencer, Michael S.,Kiely, Christopher J.,Kelly, Gordon J.,Park, Colin W.,Rosseinsky, Matthew J.,Hutchings, Graham J.
, p. 83 - 87 (2016)
Copper and zinc form an important group of hydroxycarbonate minerals that include zincian malachite, aurichalcite, rosasite and the exceptionally rare and unstable - and hence little known and largely ignored - georgeite. The first three of these minerals are widely used as catalyst precursors for the industrially important methanol-synthesis and low-temperature water-gas shift (LTS) reactions, with the choice of precursor phase strongly influencing the activity of the final catalyst. The preferred phase is usually zincian malachite. This is prepared by a co-precipitation method that involves the transient formation of georgeite; with few exceptions it uses sodium carbonate as the carbonate source, but this also introduces sodium ions - a potential catalyst poison. Here we show that supercritical antisolvent (SAS) precipitation using carbon dioxide (refs 13, 14), a process that exploits the high diffusion rates and solvation power of supercritical carbon dioxide to rapidly expand and supersaturate solutions, can be used to prepare copper/zinc hydroxycarbonate precursors with low sodium content. These include stable georgeite, which we find to be a precursor to highly active methanol-synthesis and superior LTS catalysts. Our findings highlight the value of advanced synthesis methods in accessing unusual mineral phases, and show that there is room for exploring improvements to established industrial catalysts.
The partial oxidation of methane to methanol with nitrite and nitrate melts
Lee, Bor-Jih,Kitsukawa, Shigeo,Nakagawa, Hidemoto,Asakura, Shukuji,Fukuda, Kenzo
, p. 679 - 682 (1998)
The effect of reduced oxygen species on the partial oxidation of methane to methanol was examined with nitrite melts. The experimental results support the suggestion that the formation of methanol or C2 compounds depends on different reduced oxygen species, as observed in our previous work using nitrate melts. It has been suggested that the partial oxidation of methane proceeds to CH3OH or C2 compounds via parallel pathways. This suggestion was verified by increasing the oxygen concentration to carry out the partial oxidation of methane in 25 mol% NaNO3 - 75 mol% KNO3 melts. A methanol selectivity of 8.2% and a methanol yield of 0.43% were observed with CH4/O2 = 15/1 at 575 °C, whereas with CH4/O2 = 7/1 methanol selectivity and yield increased to 23.7% and 1.1%, respectively. The results further confirm the contribution of the superoxide ion O2- on methanol formation.
Carbon dioxide hydrogenation to methanol over Cu/ZrO2/CNTs: Effect of carbon surface chemistry
Wang, Guannan,Chen, Limin,Sun, Yuhai,Wu, Junliang,Fu, Mingli,Ye, Daiqi
, p. 45320 - 45330 (2015)
Methanol synthesis from CO2 hydrogenation in a fixed-bed plug flow reactor was investigated over Cu-ZrO2 catalysts supported on CNTs bearing various functional groups. The highest methanol activity (turnover frequency 1.61 × 10-2 s-1, space time yield 84.0 mg gcat-1 h-1) was obtained over the Cu/ZrO2/CNTs catalyst (CZ/CNT-3) with CNTs functionalized by nitrogen-containing groups and Cu loading only about 10.3 wt% under the reaction conditions of 260 °C, 3.0 MPa, V(H2):V(CO2):V(N2) = 69:23:8 and GHSV of 3600 h-1. The catalysts were fully characterized by N2 physisorption, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), H2-temperature-programmed reduction (H2-TPR) and temperature-programmed desorption of H2 (H2-TPD) techniques. The excellent performance of CZ/CNT-3 is attributed to the presence of nitrogen-containing groups on the CNTs surface, which increase the dispersion of copper oxides, promote their reduction, decreases the crystal size of Cu, and enhances H2 and CO2 adsorption capability, thus leading to good catalytic performance towards methanol synthesis. This journal is
Hydrogenation of Esters by Manganese Catalysts
Li, Fu,Li, Xiao-Gen,Xiao, Li-Jun,Xie, Jian-Hua,Xu, Yue,Zhou, Qi-Lin
, (2022/01/13)
The hydrogenation of esters catalyzed by a manganese complex of phosphine-aminopyridine ligand was developed. Using this protocol, a variety of (hetero)aromatic and aliphatic carboxylates including biomass-derived esters and lactones were hydrogenated to primary alcohols with 63–98% yields. The manganese catalyst was found to be active for the hydrogenation of methyl benzoate, providing benzyl alcohol with turnover numbers (TON) as high as 45,000. Investigation of catalyst intermediates indicated that the amido manganese complex was the active catalyst species for the reaction. (Figure presented.).
Synthesis of phenol from degraded lignin using synergistic effect of iron-oxide based catalysts: Oxidative cracking ability and acid-base properties
Fumoto, Eri,Ishimaru, Hiroya,Masuda, Takao,Nakasaka, Yuta,Sato, Shinya,Yoshikawa, Takuya
, (2022/02/05)
The effects of ZrO2 and TiO2 incorporated into Fe2O3 matrix on oxidative cracking of degraded lignin and on the acid-base properties were investigated. After lignin degradation, cracking into lower-molecular-weight products was greatest using ZrO2-FeOX. Reactivity of the lattice oxygen was evaluated using H2-TPR, which revealed that the reactivity was improved. Thus, ZrO2-FeOX promoted oxidative decomposition of lignin to oligomers. In the cracking of 2-methoxyphenol, TiO2-FeOX and ZrO2-FeOX resulted in a 5- to 6-fold greater yield of phenol than the yield over Fe2O3. According to Mulliken population analysis, the charge density difference between Fe-O increased by ca. 12% in TiO2-FeOX and ZrO2-FeOX as compared with Fe2O3. This result suggests that addition of TiO2 and ZrO2 improved the acid-base properties of the catalyst, which promoted demethoxylation of 2-methoxyphenol. Thus, ZrO2-FeOX enhanced oxidative decomposition using its lattice oxygen that converted degraded lignin into lower molecule oligomers, followed by demethoxylation to produce phenol.
High catalytic methane oxidation activity of monocationic μ-nitrido-bridged iron phthalocyanine dimer with sixteen methyl groups
Kura, Jyunichi,Tanaka, Kentaro,Toyoda, Yuka,Yamada, Yasuyuki
supporting information, p. 6718 - 6724 (2021/05/26)
Herein, we report the highly potent catalytic methane oxidation activity of a monocationic μ-nitrido-bridged iron phthalocyanine dimer with 16 peripheral methyl groups. It was confirmed that this complex oxidized methane stably into MeOH, HCHO, and HCOOH in a catalytic manner in an acidic aqueous solution containing excess H2O2 at 60 °C. The total turnover number of the reaction reached 135 after 12 h, which is almost seven times higher than that of a monocatinoic μ-nitrido-bridged iron phthalocyanine dimer with no peripheral substituents. This suggests that the increased number of peripheral electron-donating substituents could have facilitated the generation of a reactive high-valent iron-oxo species as well as hydrogen abstraction from methane by the reactive iron-oxo species.