1. n. [Drilling Fluids]
A type of compound containing hydrogen and carbon atoms arranged in a symmetrical 6-carbon ring structure with single (C-C) and double (C=C) bonds alternating around the ring. Rings are single, multiple or fused and can have other chemical groups attached in place of hydrogen. Benzene, C6H6 is the simplest single-ring aromatic, napthalene, C10H8, the simplest fused-ring aromatic and toluene is the simplest aromatic, having an alkyl side chain, C6H5-CH3. Xylene, a common oilfield chemical, has two methyl side chains, C6H4-(CH3)2. Aniline is the simplest aromatic amine, C6H5-NH2 and is used in the aniline point test. Aromatic hydrocarbons in oils used to prepare oil-base mud can damage elastomers and increase the toxicity of the fluid. The aniline point test is used for screening oils to infer aromatic content.