Maleic Acid | Properties, Preparation, Uses |

Maleic Acid.

It is prepared commercially past times catalytic oxidation of 2-butene (from petroleum) or benzene.

Properties of Maleic Acid.

Maleic acid crystallises inward large monoclinic prisms, mp 130.5°C, having repulsive astringent taste. It is really soluble inward H2O together with ethyl alcohol, simply moderately soluble inward ether. It gives the reaction of a dicarboxylic acid together with besides of an activated carbon-carbon double bond.

(1) Action of Heat. On heating to 150°C, it dehydrates to cast maleic anhydride.

(2) Catalytic Hydrogenation. When hydrogenated inward the presence of Raney nickel, it forms succinic acid.

(3) Hydration. It adds molecule of H2O across the double bond inward the presence of a mineral acid, yielding maleic acid.

(4) Reaction amongst Alkaline KMnO4. When treated amongst alkaline metal KMnO4 solution, undergoes hydroxylation to cast meso-tartaric acid.

Maleic Acid Uses.

Maleic acid is used.

1. For preparing succinic acid, malic acid, tartaric acid, fumaric acid, together with several other derivatives.
2. As maleic anhydride for polyester resins needed inward fibrous drinking glass material, widely used since 1971 for structure of cars, boats, bathroom, gasoline storage tanks, etc.
3. As mordant
4. As preservative for oils together with fats.