Methanol

April 4, 2005Metabolism 1Names of Team Members

Why Study this Topic

One of the simplest and one of the most important alcohols

Has multiple uses Don’t mistake it with ethanol alcohols

which are drinkable Can be used for industrial reasons It eases life

Background

Definition Methanol (methyl alcohol) is produced

from the distillation of wood and is a clear, colorless, volatile liquid with a weak odor that is somewhat sweeter than ethanol

Background cont.

The chemical property is CH3OH Forms a methyl group

The carbon bonded with three hydrogen’s creates the methyl group

H |H – C – O – H | H

Background cont.

Uses of Methanol Fuel Windshield wiper fluids and de-icers Antifreeze Cleaners Canned heat Paints, Varnishes, Paint Thinners and

Removers

History

First used by Egyptians by pyrolysis of wood Robert Boyle isolated pure methanol in 1661 Jean-Baptist Dumas and Eugene Peligot

determined its elemental composition in 1834 Introduced the word methylene to organic chemistry,

from the Greek words methu, meaning "wine," and hyle, meaning "wood"

Methyl derived in 1840 from methylene, and then applied to describe methyl alcohol; shortened to methanol in 1892 by the International Conference on Chemical Nomenclature

Chemical Principles

Melting Point -97.8OC

Boiling Point 64.7OC

Chemical Properties cont.

Production Synthesis gas is usually produced from

the methane in natural gas rather than from coal

At moderate pressures (10–20 atm) and high temperatures (around 850°C), methane reacts with steam on a nickel catalyst to produce syngas

CH4 + H2O CO + 3H2

Chemical Properties cont.

Production cont. Carbon monoxide and hydrogen react on

a second catalyst to produce methanol Most widely used catalyst is a mixture of

copper, zinc oxide, and alumina At 50–100 atm and 250°C, it can catalyze

the production of methanol from carbon monoxide and hydrogen

CO + 2H2 CH3OH

Chemical Principles cont.

Combustion Over several days,

atmospheric methanol is oxidized by oxygen and sunlight to carbon dioxide

Methanol burns in air forming carbon dioxide and water

2CH3OH + 3O2

2CO2 + 4H2O

A methanol flame is almost colorless

Health and Safety

Methanol is toxic: It metabolites formic acid and formaldehyde

which causes blindness and death Enters the body by ingestion, inhalation, or

absorption through the skin If ingested, a doctor should be contacted

immediately. Fatal dose: 100–125 mL (4 oz.)

Treatment: Injection of ethanol: it slows down the

breakdown of methanol by the liver

Heath and Safety

Symptoms Poisonous by ingestion or inhalation May cause respiratory failure, kidney

failure, and blindness Skin contact can cause dermatitis headache, dizziness, nausea, lack of

coordination, confusion, drowsiness, followed by unconsciousness and death

Pros and Cons

Pros Does not

contribute to air pollution

Less toxic to plants and animals then conventional gasoline or diesel

Biodegradable

Less flammable and safer to handle then gasoline

Made from renewable resources

Runs cooler then gasoline in vehicles

Pros and Cons cont.

Cons Highly corrosive and has no lubricating

qualities Expensive to produce on a large scale Freezes at a temperature that is

reasonably reached by outside temperature, during winter

References

Baird, Colin; Gloffke, Wendy. Chapter 6. Chemistry in Your Life. W.H. Freeman and Company. New York, 2003

Consumer Energy Council of America. Alternative Fuels and Fuel Additives. http://www.cecarf.org/Programs/Fuels/Fuelfacts/Alternativefuels.html. (29, March 2005)

Dictionary.Laborlaw.com. Methanol. http://encyclopedia.laborlawtalk.com/Methanol. (29, March 2005)

EMBBS: Bringing PhysiciansTogether Worldwide. Methanol. http://www.embbs.com/cr/alc/alc6.html. (29, March 2005)