Comparative Study Methanol Vs Ethanol
Sr. No.
|
Parameters
|
Methanol
|
Ethanol
|
1
|
Systematic name
|
Methanol
|
Ethanol
|
2
|
Class
|
Class 2
|
Class 3
|
3
|
Chemical Formula
|
CH3OH
|
|
4
|
Chemical Structure
|
||
5
|
CAS number
|
67-56-1
|
64-17-5
|
6
|
702
|
||
7
|
864
|
682
|
|
8
|
Y4S76JWI15
|
3K9958V90M
|
|
9
|
EC number
|
200-659-6
|
200-578-6
|
10
|
1230
|
1170
|
|
11
|
D02309
|
D00068
|
|
12
|
Methanol
|
Ethanol
|
|
13
|
CHEBI:17790
|
CHEBI:16236
|
|
14
|
CHEMBL545
|
||
15
|
RTECS number
|
PC1400000
|
KQ6300000
|
16
|
Beilstein Reference
|
1098229
|
1718733
|
17
|
Gmelin Reference
|
449
|
787
|
18
|
3DMet
|
B01170
|
B01253
|
19
|
Molecular formula
|
CH4O
|
C2H6O
|
20
|
Molar mass
|
32.04 g mol−1
|
46.07 g mol−1
|
21
|
Physical Appearance
|
Methanol ‘“is a
colorless liquid that is also extremely volatile. Its odor is distinctive and
it burns as a bright white flame
|
Ethanol ‘“is a
colorless liquid that is extremely volatile. It has a strong, burning odor
and will burn as a bright blue flame.
|
22
|
Density
|
0.7918 g/cm3
|
0.789 g/cm3 (at 20°C)
|
23
|
Melting point
|
-97.6 °C,
176 K, -144 °F
|
−114 °C,
159 K, -173 °F
|
24
|
Boiling point
|
64.7 °C,
338 K, 148 °F
|
78.37 °C, 352 K, 173 °F
|
25
|
log P
|
-0.69
|
-0.18
|
26
|
Vapor pressure
|
13.02 kPa (at 20 °C)
|
5.95 kPa (at 20 °C)
|
27
|
Acidity (pKa)
|
15.5
|
15.9
|
28
|
Refractive index (nD)
|
1.33141
|
1.361
|
29
|
Viscosity
|
5.9×10−4 Pa
s (at 20 °C)
|
0.0012 Pa s (at 20
°C), 0.001074 Pa s (at 25 °C)
|
30
|
Dipole moment
|
1.69 D
|
1.69 D
|
31
|
European Union
classification
|
F
T
|
F
|
32
|
Flash point
|
11–12 °C
|
13–14 °C
|
33
|
Concentration limit in
Extract
|
3000
ppm
|
5000
ppm
|
34
|
Auto ignition
temperature |
385 °C
|
363 °C
|
Sr. No.
|
Parameters
|
Methanol
|
Ethanol
|
35
|
Risk assessment
|
Class 2 solvents to e
limited nongenotoxic animal carcinogens or possible causative agent of other
irreversible toxicity such as neurotoxicity, or teratogenicity
|
Class 3 solvents with
low toxic potential to humans; no health based exposure limit is needed
|
36
|
Hazards Identification
|
POISON! DANGER! VAPOR HARMFUL. MAY BE FATAL OR CAUSE BLINDNESS IF
SWALLOWED. HARMFUL IF INHALED OR ABSORBED THROUGH SKIN. CANNOT BE
MADE NONPOISONOUS. FLAMMABLE LIQUID AND VAPOR. CAUSES IRRITATION TO
SKIN, EYES AND RESPIRATORY TRACT. AFFECTS CENTRAL NERVOUS SYSTEM AND LIVER.
|
WARNING! FLAMMABLE LIQUID AND VAPOR. MAY FORM EXPLOSIVE PEROXIDES IN AIR.
HARMFUL IF SWALLOWED, INHALED OR OBSORBED THROUGH SKIN. CAUSES IRRITATION TO
EYES AND RESPIRATORY TRACT. AFFECTS CENTRAL NERVOUS SYSTEM, BLOOD AND BLOOD
FORMING ORGANS, REPRODUCTIVE SYSTEM, LIVER
AND KIDNEYS. POSSIBLE BIRTH DEFECT HAZARD. MAY CAUSE BIRTH DEFECTS
BASED ON ANIMAL DATA. MAY CAUSE IRRITATION TO SKIN.
|
37
|
Inhalation
|
A slight irritant to
the mucous membranes. Toxic effects exerted upon nervous system, particularly
the
optic nerve. Once
absorbed into the body, it is very slowly eliminated. Symptoms of
overexposure may
include headache,
drowsiness, nausea, vomiting, blurred vision, blindness, coma, and death. A
person may
get better but then
worse again up to 30 hours later.
|
Causes irritation to
the respiratory tract. Symptoms may include sore throat, coughing, headache,
nausea
and shortness of
breath. High concentrations have a narcotic effect.
|
38
|
Ingestion
|
Toxic. Symptoms
parallel inhalation. Can intoxicate and cause blindness. Usual fatal dose:
100-125
milliliters.
|
Swallowing may cause
nausea, vomiting, abdominal pain, breathing difficulties, weakness. Liver and
kidney damage may
result from swallowing large quantities of the material.
|
Sr. No.
|
Parameters
|
Methanol
|
Ethanol
|
39
|
Skin Contact
|
Methyl alcohol is a
defatting agent and may cause skin to become dry and cracked. Skin absorption
can occur; symptoms may parallel inhalation exposure.
|
May cause irritation
with redness and pain. May be absorbed through the skin with possible
systemic
effects.
|
40
|
Eye Contact
|
Irritant. Continued
exposure may cause eye lesions.
|
Vapors are irritating
and may produce immediate pain, redness and tearing. Splashes can cause
severe pain, stinging, swelling.
|
41
|
Chronic Exposure
|
Marked impairment of
vision has been reported. Repeated or prolonged exposure may cause skin
irritation.
|
Prolonged exposure may
cause injury to bone marrow, blood cells, kidney, liver and reproductive
system. A suspected human reproductive and birth defectHazard.
|
42
|
Aggravation of Pre-existing Conditions
|
Persons with
pre-existing skin disorders or eye problems or impaired liver or kidney
function may be more susceptible to the effects of the substance.
|
Persons with
pre-existing blood or central nervous system disorders may be more
susceptible to the effects of this substance.
|
43
|
Accidental Release Measures
|
Ventilate area of leak
or spill. Remove all sources of ignition. Wear appropriate personal
protective equipment. Isolate hazard area. Keep unnecessary and unprotected
personnel from
entering. Contain and
recover liquid when possible. Use non-sparking tools and equipment. Collect
liquid in an appropriate container or absorb with an inert material (e. g.,
vermiculite, dry sand, earth), and place in
a chemical waste
container. Do not use combustible materials, such as saw dust. Do not flush
to sewer! If a leak or spill has not ignited, use water spray to disperse the
vapors, to protect personnel attempting to stop
leak, and to flush
spills away from exposures. US Regulations (CERCLA) require reporting spills
and releases to soil, water and air in excess of reportable quantities. The
toll free number for the US Coast Guard National Response Center is (800)
424-8802.
|
Ventilate area of leak
or spill. Remove all sources of ignition. Wear appropriate personal
protective
equipment. Isolate
hazard area. Keep unnecessary and unprotected personnel from
entering. Contain and
recover liquid when possible. Use non-sparking tools and equipment. Collect
liquid
in an appropriate
container or absorb with an inert material (e. g., vermiculite, dry sand,
earth), and place in a chemical waste container. Do not use combustible
materials, such as saw dust. Do not flush to sewer! If a leak or spill has
not ignited, use water spray to disperse the vapors, to protect personnel
attempting to stop leak, and to flush spills away from exposures. US
Regulations (CERCLA) require reporting spills and releases to soil, water and
air in excess of reportable quantities. The toll free number for the US Coast
Guard National Response Center is (800) 424-8802.
|
Sr. No.
|
Parameters
|
Methanol
|
Ethanol
|
44
|
Fire Fighting Measures
|
Use alcohol foam, dry
chemical or carbon dioxide. (Water may be ineffective.)
|
Water spray, dry
chemical, alcohol foam, or carbon dioxide. Water spray may be used to keep
fire exposed
Containers cool. Water
may be used to flush spills away from exposures and to dilute spills to
nonflammable
Mixtures.
|
45
|
Handling and Storage
|
Protect against
physical damage. Store in a cool, dry well-ventilated location, away from any
area where the fire hazard may be acute. Outside or detached storage is
preferred. Separate from incompatibles.
Containers should be
bonded and grounded for transfers to avoid static sparks. Storage and use
areas should be No Smoking areas. Use non-sparking type tools and equipment,
including explosion proof ventilation.
Containers of this
material may be hazardous when empty since they retain product residues
(vapors, liquid); observe all warnings and precautions listed for the product.
Do Not attempt to clean empty containers since residue is difficult to
remove. Do not pressurize, cut, weld, braze, solder, drill, grind or
expose such containers
to heat, sparks, flame, static electricity or other sources of ignition: they
may explode and cause injury or death.
|
Protect against
physical damage. Store in a cool, dry well-ventilated location, away from any
area where
the fire hazard may be
acute. Outside or detached storage is preferred. Separate from incompatibles.
Containers should be bonded
and grounded for transfers to avoid static sparks. Storage and use areas
should be No Smoking areas. Use non-sparking type tools and equipment,
including explosion proof ventilation.
Containers of this
material may be hazardous when empty since they retain product residues
(vapors,
liquid); observe all
warnings and precautions listed for the product. Sudden release of hot
organic chemical vapors or mists from process equipment operating at elevated
temperatures and pressure, or sudden ingress of air into vacuum equipment,
may result in ignitions without the presence of ignition sources. Published
"autoignition" or "ignition" temperature values cannot be
treated as safe operating temperatures in chemical
processes without
analysis of the actual process conditions.
|
46
|
Stability
|
Stable under ordinary
conditions of use and storage.
|
Stable under ordinary
conditions of use and storage. Do not distill to dryness. Avoid excessive
temperatures or prolonged reflux, such as in batch distillations. Formation
of explosive peroxides
|
Sr. No.
|
Parameters
|
Methanol
|
Ethanol
|
has been reported from
auto-oxidation.
Reported to dissolve aluminum from scratched or heated aluminum surfaces.
|
|||
47
|
Hazardous Decomposition Products
|
May form carbon
dioxide, carbon monoxide, and formaldehyde when heated to decomposition.
|
Carbon dioxide and
carbon monoxide may form when heated to decomposition
|
48
|
Hazardous Polymerization
|
Will not occur
|
Will not occur
|
49
|
Incompatibilities
|
Strong oxidizing
agents such as nitrates, perchlorates or sulfuric acid. Will attack some
forms of plastics, rubber, and coatings. May react with metallic aluminum and
generate hydrogen gas.
|
Strong oxidizers,
strong acids, strong bases, copper, aluminum.
|
50
|
Conditions to Avoid
|
Heat, flames, ignition
sources and incompatibles
|
Heat, flame, ignition
sources, air, incompatibles
|
51
|
Toxicological Data
|
Methyl
Alcohol (Methanol) Oral rat LD50: 5628 mg/kg; inhalation rat LC50: 64000
ppm/4H; skin rabbit LD50: 15800 mg/kg; Irritation data-standard Draize test:
skin, rabbit: 20mg/24 hr. Moderate; eye, rabbit: 100 mg/24 hr. Moderate.
Investigated as a mutagen, reproductive effector.
|
Oral
rat LD50: 2125 mg/kg; inhalation rat LC50: 2000 ppm/7H; irritation eye
rabbit, standard Draize: 50 mg moderate; skin rabbit, standard Draize: 500 mg
open mild; investigated as a tumorigen, mutagen, reproductive effector.
|
52
|
Extraction
|
Usually Methanol is
more powerful for extraction
|
Ethanol loses some
quantity of extraction efficiency for polar components. it is more food
friendly solvent
|
53
|
Reactions with Water
|
Methanol ‘“is soluble
in water, which means that it will break down in the presence of water.
|
Ethanol ‘“is miscible
in water, which means that the two substances easily combine to make a
homogenous solution.
|
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