Effect of cetyl trimethyl ammonium bromide on shrinkage cracks in filter cakes during pressure filtration of iron ore concentrates

Abstract

During the dewatering process of iron ore concentrates, the formation of shrinkage cracks severely interferes with the filtration process and causes high cake moisture. Until now, effective countermeasures and mechanism study about shrinkage cracks are still insufficient. In the previous researches, capillary forces have been considered to be the driving potential for the shrinkage cracks, which were related with liquid surface tension and particle contact angle. Thus, surface tension and contact angle were both changed in this paper by using a cationic surfactant, cetyl trimethyl ammonium bromide (CTAB). Moreover, the zeta potential, adsorbance and infrared spectra were respectively measured before and after CTAB coating to analyze the change of interfacial properties and the influence on the extent of shrinkage cracks. The results indicate that the tendency of filter cakes to form shrinkage cracks can be weakened with the decrease of capillary forces.