Synthesis of sulphonated naphthalene-formaldehyde condensates and their trace-analytical determination in wastewater and river water

Naphthalene sulphonates and their derivatives such as condensates with formaldehyde, are widely used for a variety of industrial applications, e.g. as plasticisers for concrete and as tanning agents. Owing to the complex structure they are incompletely broken down during conventional sewage treatment and their high solubility results in their presence in the aquatic environment. The synthesis of several such compounds in the laboratory, and the use of the resulting condensates as reference materials in the chromatographic determination of trace contaminants in various water samples, are described. Characteristic peaks observed during the HPLC screening of wastewater and river water samples were compared with those produced by synthetic model compounds. Three paths were identified as possible routes of entry of these materials into the aquatic environment. The target compounds were present at levels in the range 0.14 to 110 ug per litre. There are 35 references.