An experimental evaluation of the metal cleaning performance of four alkali
ne aqueous cleaner formulations and surfactant recovery by membrane filtrat
ion from mixtures with model oil contaminants was carried out. It was found
that an adequate cleaning effect might be combined with good recycling pro
perties. A rapid screening procedure for metal cleaning was combined with a
simple colorimetric method and COD analysis for oil removal and surfactant
recovery assays, respectively. Physico-chemical characterization of deterg
ents over a wide range of temperatures and concentrations showed important
differences in phase separation and aggregational behaviour and correlation
s with oil separation and surfactant recovery results were inferred.