Synergistic effect of surfactant combinations as dewatering aids for alumina trihydrate

摘要

The invention is directed towards methods and compositions for treating slurry to better dewater alumina trihydrate precipitated from the Bayer process. The method comprises using a product comprising the combination of at least two surfactants together with an optional coupling agent to treat the alkaline slurry with certain amount of alumina trihydrate present. Synergistic effects between binary combinations of nonionic and anionic surfactants result in more efficient dewatering aids for alumina trihydrate slurry when combinations of such surfactants are applied. A coupling agent may be used in formulations to reduce viscosity of such surfactant combinations, allowing the practical application of such products.