- The chemical compound furfural is an industrial chemical derived from a variety of agricultural byproducts, including corncobs, oat and wheat bran, and sawdust.
- The name furfural comes from the Latin word furfur, meaning bran, referring to its usual source.
- Furfural is an aromatic aldehyde, with the ring structure shown at right. Its chemical formula is C5 H4 O2. In its pure state, it is a colorless oily liquid with the odor of almonds, but upon exposure to air it quickly becomes yellow.
- Furfural is produced from agricultural waste biomass that contain pentosans, which are aldose sugars, composed of small rings formed from short five-member chains, that constitute a class of complex carbohydrates, present in cellulose of many woody plants such as corn cobs, sugar cane bagasse, rice and oat hulls etc
- Furfural is produced in a digester under high-pressure steam, from where it is recovered by steam distillation, followed by water-furfural separation and purification.
- In the first step pentosans are hydrolyzed by strong mineral acids to monomeric C5-sugars. Subsequent cyclodehydration of the pentoses yields Furfural.
- Furfural is used as a solvent in petrochemical refining to extract dienes (which are used to make synthetic rubber) from other hydrocarbons.
- Furfural, as well as its derivative furfuryl alcohol, can be used either by themselves or in together with phenol, acetone, or urea to make solid resins. Such resins are used in making fiberglass, some aircraft components, and automotive brakes.
- Furfural is also used as a chemical intermediate in the production of the solvents furan and tetrahydrofuran. Hydroxymethylfurfural has been identified in a wide variety of heat processed foods.
- China is the world's largest producer of both furfural and furfuryl alcohol. Chinese production of both materials has been increasing significantly. Furfural and furfuryl alcohol production in China is expected to increase at an average annual rate of about 5% over the next five years.
- The largest market for furfural had been for the production of furfuryl alcohol, but since Japanese furfural alcohol producers ceased manufacturing, the largest market is now lube oil refining.
- The largest producers of furfural are China and the Central Romana Corporation in the Dominican Republic. World operating capacity is estimated to be approaching 225 thousand metric tons per year.