Study of the Biodegradability of Sodium Salt from the Condensation Product of Naphthalene Sulphonic Acids and Formaldehyde

The biodegradability of dispersants (naphthalenesulfonate formaldehyde condensates), used with disperse dyes, has been evaluated using different techniques such as chemical oxygen demand (COD), UV-spectroscopic analysis and tonometry. A biomass was used from industrial waste water which was acclimated for six months prior to use. The study has shown that biodegradation involves two steps: first, the cleavage of the CH2 bridges; second, the degradation of the aromatic nuclei. We identified a series of bacteria (Pseudomonas cepacia, Pseudomonas vesicularis, Pseudomonas stutzeri, Pseudomonas pichetti, Shevanella putrefacians, Agrobacterium radiobacter and Aeromonas hydrophila) that proved to biodegrade the dispersant very efficiently.