Furfural

 ( Conjugated Dienes ) 

• See also: George Fownes named this oil "furfurol" in 1845 (from furfur (bran), and oleum (oil)). In 1848, the French chemist Auguste Cahours determined that furfural was an aldehyde. (English translation: ) Determining the structure of furfural required some time: the furfural molecule contains a cyclic ether (furan), which tends to break open when it's treated with harsh reagents. In 1870, German chemist Adolf von Baeyer speculated about the structure of the chemically similar compounds furan and 2-furoic acid. Additional research by German chemist Heinrich Limpricht supported this idea. From p. 90: "Die Ansicht, dass die Pyroschleimsäure eine der Salicylsäure ähnliche Constitution besitzt, macht das Auftreten des Tetraphenols bei der Destillation der pyroschleimsauren Salze wahrscheinlich." (The belief that 2-furoic acid has a structure similar to salicylic acid makes probable the presence of tetraphenol furan during the distillation of salts of 2-furoic acid.) That is, just as heating salts of salicylic acid produces phenol, so heating salts of 2-furoic acid should produce an analog of phenol containing 4 carbon atoms. From work published in 1877, Baeyer had confirmed his previous belief on the structure of furfural.In 1877, Baeyer published a series of papers on furfural, as he tried to determine its structure.
• By 1886, furfurol was being called "furfural" (short for "furfuraldehyde") and the correct chemical structure for furfural was being proposed. By 1887, the German chemist Willy Marckwald had inferred that some derivatives of furfural contained a furan nucleus. In 1901, the German chemist Carl Harries determined furan's structure through work with Succinaldehyde and 2-methylfuran, thereby also confirming furfural's proposed structure.

Furfural remained relatively obscure until 1922, when the Quaker Oats Company began mass-producing it from oat hulls. Today, furfural is still produced from agricultural byproducts like bagasse and corn cobs. The main countries producing furfural today are the Dominican Republic, South Africa and China.

Furfural participates in the same kinds of reactions as other aldehydes and other aromatic compounds. It exhibits less aromatic character than benzene, as can be seen from the fact that furfural is readily hydrogenation to tetrahydrofurfuryl alcohol. When heated in the presence of acids, furfural irreversibly polymerizes, acting as a thermosetting polymer.

xylose → + 3

These sugars may be obtained from obtained from hemicellulose present in lignocellulosic biomass.

Between 3% and 10% of the mass of crop residue feedstocks can be recovered as furfural, depending on the type of feedstock. Furfural and water evaporate together from the reaction mixture, and separate upon condensation. The global production capacity is about 800,000 tons as of 2012. China is the biggest supplier of furfural, and accounts for the greater part of global capacity. The other two major commercial producers are Illovo Sugar in South Africa and Central Romana in the Dominican Republic.

In the laboratory, furfural can be synthesized from plant material by heating with sulfuric acid or other acids.

In industrial production, some lignocellulosic residue remains after the removal of the furfural. This residue is dried and burned to provide steam for the operation of the furfural plant. Newer and more energy efficient plants have excess residue, which is or can be used for co-generation of electricity,

In petrochemical industry, furfural is utilized as a specialized chemical solvent for diene extraction.

Furfural is an important renewable, non-petroleum based, chemical feedstock which can be converted into solvents, polymers, fuels and other useful chemicals by a range of catalytic Redox.

Hydrogenation of furfural provides furfuryl alcohol (FA), which is used to produce , which are exploited in thermoset polymer matrix composites, cements, adhesives, casting resins and coatings.