1. Combustion of Methanol:
Methanol burns with a pale-blue, non-luminous flame to form carbon dioxide and steam.
3OH + 3O2 ===> 2CO2 + 4H2O
2. Oxidation of Methanol:
Methanol is oxidized with acidified Potassium Dichromate (K2Cr2O7) or with acidified Sodium Dichromate (Na2Cr2O7) or with acidified Potassium Permanganate (KMnO4) to form formaldehyde.
CH3OH ===> HCHO + H2
If the oxidizing agent is in excess, the formaldehyde is further oxidized to formic acid and then to carbon dioxide and water.
HCHO ===> HCOOH ===> CO2 + H2O
3. Catalytic Oxidation of Methanol:
The catalytic oxidation of methanol using platinum wire is of interest as it is used in model aircraft engines to replace the sparking plug arrangement of the conventional petrol engine. The heat of reaction is sufficient to spark the engine.
4. Dehydrogenation of Methanol:
Methanol can also be oxidized to formaldehyde by passing its vapor over copper heated to 300 °C. Two atoms of hydrogen are eliminated from each molecule to form hydrogen gas and hence this process is termed dehydrogenation.
CH3OH ===> HCHO + H2
5. Dehydration of Methanol:
Methanol does not undergo dehydration reactions. Instead, in reaction with sulphuric acid the ester, dimethyl sulphate is formed.
2CH3OH ===> (CH3)2SO4 + H2O
6. Esterification of Methanol:
Methanol reacts with organic acids to form esters.
CH3OH + HCOOH ===> HCOOCH3 + H2O
7. Substitution of Methanol with Sodium:
Methanol reacts with sodium at room temperature to liberate hydrogen. This reaction is similar to the reaction of sodium with ethanol.
2CH3OH + 2Na ===> 2CH3ONa + H2
8. Substitution of Methanol with Phosphorus Pentachloride
Methanol reacts with phosphorus pentachloride at room temperature to form hydrogen chloride, methyl chloride, (i.e. chloroethane) and phosphoryl chloride.
CH3OH + PCl5 ===> HCl + CH3Cl + POCl3
9. Substitution of Methanol with Hydrogen Chloride:
Methanol reacts with hydrogen chloride to form methyl chloride (i.e. chloromethane) and water. A dehydrating agent (e.g. zinc chloride) is used
CH3OH + HCl ===> CH3Cl + H2O