REDUCTIVE DEHALOGENATION OF CHLOROANILINES IN ANAEROBIC ESTUARINE SEDIMENT

The reductive dehalogenation of chloroanilines (CAs) was investigated in anaerobic sediment/water systems. The sulfate content of the inters titial and overlaying waters was approximately 20 mmoles 1(-1) and the sediment was apparently sulfidogenic. The CAs exhibited first-order d isappearance kinetics with the rate constants ranging from 0.012-0.005 day(-1) or half-lives between 40 and 672 days. Pentachloroaniline TPe CA), 2,3,4,5-tetrachloroaniline (2,3,4,5-TeCA) and 3,4,5-trichloroanil ine (3,4,5-TCA) were transformed by the sequential removal of halogen from the para and ortho positions. The disappearance of the parent com pound and accumulation of metabolites were simulated using a first-ord er branched kinetic model.