Effect Of Surfactants On Flotation Of Diaspore By Sodium Oleate

The poor recovery of fine particles and decreasing of collection ability at low temperature exist in the flotation of bauxite when fatty acids used as collectors. This phenomenon is similar to the flotation of other oxide ores. To solve this problem, mixed reagents used. In this work, sodium oleate used as the main collector and combined with other eight kinds of surfactants such as anionic surfactants, nonionic surfactants and long chain fatty alcohol respectively. With a systematic study on the effect and mechanism of surfactants on flotation of diaspore by sodium oleate, and following results were obtained:When sodium oleate was used as the collector, the flotability of the-5μm diaspore was under the average value significantly. And the collecting ability was sensitive to the temperature, which is weak when the pulp temperature is below 20℃, especially the the recovery of the-5μm decrease mostly.There was barely no collecting ability of selected 8 kinds of surfactants on diaspore, but obvious influence appeared when the proportion between other surfactants and sodium oleate is 1:9. The collecting ability changed as follows:(1)it was strengthened remarkably with the addition of sulfonate (SDS) at low temperature(10℃); (2)it was strengthened more with the addition of myristic acid at normal temperature; (3)it was improved with the addition of Tween80 at normal temperature, but had little change at low temperature; (4)it was strengthened with the addition of octanol. All of the positive effects improve the recovery of fine diaspore. However, there is no remarkable changes of aggregation observed by particle size analysis. The negative effects would appear with the addition of palmitic acid, TX-100 or Tween60. Particularly with the adding of palmitic acid, the collecting ability of sodium oleate decreased seriously under low temperature.The results of electric conductivity measurement, IR spectroscopy and calculation of surface active parameter of mixed surfactants show that, the interaction between surfactants and sodium oleate leads to the changes of properties of mixed surfactants aqueous or appearance of co-adsorption on the diaspore, therefore, the collecting ability of sodium oleate on diaspore changed.