Diethylbenzene (DEB) refers to any of three

isomer In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers. Iso ...

s with the formula C₆H₄(C₂H₅)₂. Each consists of a benzene ring and two

ethyl Ethyl may refer to: Arts and entertainment * Cold Ethyl, a Swedish rock band *Ethyl Sinclair, a character in the ''Dinosaurs'' television show Science and technology * Ethyl group, an organic chemistry moiety * Ethyl alcohol (or ethanol) * E ...

substituents. The meta and para have the greater commercial significance. All are colorless liquids.

Nomenclature

* ''Ortho'': known as 1,2-diethylbenzene and ''o''-diethylbenzene. * ''Meta'': known as 1,3-diethylbenzene and ''m''-diethylbenzene. * ''Para'': known as 1,4-diethylbenzene and ''p''-diethylbenzene.

Production and applications

Diethylbenzenes arise as side-products of the alkylation of benzene with ethylene, which can described as two steps. The first step is the industrial route to ethylbenzene, which is produced on a large scale as a precursor to styrene. :C₆H₆ + C₂H₄ → C₆H₅C₂H₅ The diethylbenzene is an inadvertent side product. :C₆H₅C₂H₅ + C₂H₄ → C₆H₄(C₂H₅)₂ Using shape-selective zeolite catalysts, the para isomer can be produced in high selectivity. Much diethylbenzene is recycled by transalkylation to give ethylbenzene: : C₆H₄(C₂H₅)₂ + C₆H₆ → 2 C₆H₅C₂H₅

Uses

Diethylbenzene is used in a mixture with methyl and/or ethyl biphenyls as a low temperature heat transfer fluid. Diethylbenzene is dehydrogenated to give divinylbenzene (DVB): : C₆H₄(C₂H₅)₂ → C₆H₄(C₂H₃)₂ + 2 H₂ DVB is used in the production of crosslinked polystyrene.

References

{{reflist Alkylbenzenes