Treatment of Anionic Emulsion Systems Using Chitosan, Polyacrylamide and Aluminum Sulfate

PINOTTI, A; BEVILACQUA, A; ZARITZKY, N

Journal of Scanning Microscopies

FAMS, Inc., D. C. Joy (Ed)

Año: 1999 vol. 21 p. 354 - 358

The presence of emulsified oil in waste water of edible fats industry can interfere with many tertiary or advanced wastewater  treatments such as adsorption, filtration  and various membrane techniques  and can cause severe problems in the step of biological treatment. The objective of the present work was to compare the performance of three destabilizers: chitosan, polyacrylamide and aluminum sulfate to flocculate an O/W emulsion  formulated with different emulsifiers (sodium dodecyl sulfate and sodium tetradecyl sulfate). Experiments were performed on a model system constituted by sunflower oil/water emulsions.  Methods used were: turbidimetry, colloidal titration and microscopic observation. Results showed that the increase of surfactant chain length increases the destabilizer dose necessary to produce destabilization and reaching zero charge. In chitosan and polyacrylamide treatments redispersion was observed for both SDS and STS emulsions. In the case of treatment with aluminum sulfate, turbidity values remained nearly constant, showing that redispersion does not take place in this case.