Furfural is a viscous, colorless, oily liquid with the odor of almonds. Upon exposure to air it turns dark brown or black. Furfural is miscible with almost organic solvents excluding alkanes; boundedly soluble in water. It forms azeotrope with water.
Furfural is produced from hemicellulose (pentosan) containing raw material. When heated with dilute mineral acids, hemicellulose undergoes hydrolysis to yield sugars, principally xylose. Under the same conditions of heat and acid, xylose and other five carbon sugars undergo dehydration, losing three water molecules to become furfural.
as a parent compound to make furane, sylvan, furfuryl alcohol, tetrahydrofurane (THF);
to manufacture solid resins by themselves or in together with phenol, acetone, or urea (e.g. fiberglass);
as a fungicide and weed killer;
to prepare pharmaceuticals (e.g. furacillin);
to make pesticides;
as an extracting solvent for refining lubricating oils and butadiene extraction from other hydrocarbons;