Treatment of anionic emulsion systems using chitosan, polyacrylamide, and aluminum sulfate

The presence of emulsified oil in waste water of the edible fats industry c an interfere with many tertiary or advanced waste water treatments such as adsorption, filtration, and various membrane techniques, and can cause seve re problems in the step of biological treatment. The objective of the prese nt work was to compare the performance of three destabilizers: chitosan, po lyacrylamide, and aluminum sulfate to flocculate an O/W emulsion formulated with different emulsifiers (sodium dodecyl sulfate and sodium tetradecyl s ulfate). Experiments were performed on a model system constituted by sunflo wer oil/water emulsions. Methods used were turbidimetry, colloidal titratio n, and microscopic observation. Results showed that the increase of surfact ant chain length increases the destabilizer dose necessary to produce desta bilization and reaching zero charge. In chitosan and polyacrylamide treatme nts, redispersion was observed for both sodium dodecyl sulfate and sodium t etradecyl sulfate emulsions. In the case of treatment with aluminum sulfate , turbidity values remained nearly constant, showing that redispersion does not take place in this case.