Migration behavior of aromatic amines on alumina thin layers developed with water-in-oil microemulsion

Water-in-oil (w/o) microemulsions consisting of surfactant [sodium dodecyl sulfate (SDS) or N-Cetyl-N,N,N-trimethyl ammonium bromide], water, heptane or hexane, and a cosurfactant (l-pentanol or butanol) have been used as a m obile phase in combination with alumina, microcrystalline cellulose, silica gel G, silica gel H, and Kieselguhr thin layers to study the retention eff iciency of amines. The separation of amines from their ternary and binary m ixtures is achieved. Thin layers of alumina as the stationary phase and SDS /water/heptane/1-pentanol microemulsion as mobile phase is identified as th e best chromatographic system for amine analysis. The limits of identificat ion and dilution are reported for amines. Effects of heavy metals, anions, and phenols on the separation efficacy of diphenylamine-p-chloroaniline-p-n itroaniline have also been examined. The effect of electrolyte in the micro emulsion on amine mobility is investigated. The o- and p-isomers move faste r compared to the m-isomer of aniline.