Effects of various fillers on anionic polyacrylamide systems for treating kaolin suspensions

This study examines the effects of different types of salt fillers and salt filler loadings on anionic polyacrylamide (A-PAM). Urea, potassium chloride, sodium chloride, and sodium sulfate were incorporated into the A-PAM solution with 10, 20, and 30 wt.% loadings. The characteristics of the A-PAM solution were measured based on the dissolution rate, viscosity, potential, turbidity reduction and floc size. The introduction of salt fillers increased the dissolution rate and reduced the viscosity based on the electrolyte strength of the salt fillers. Stronger electrolytes showed an increased dissolution rate, decreased viscosity, increased turbidity reduction, and decreased floc size. Stronger electrolytes also showed fluctuating and uneven values in the (zeta) potential due to the uneven placement of ions in the A-PAM solution system. The urea-filled A-PAM showed a potential trend similar to that of the unfilled A-PAM. It can be concluded that the strength of ion dissociation plays an important role in the dissolution rate, viscosity, and flocculation characteristics of a salt-filled A-PAM solution. (C) 2013 Elsevier B.V. All rights reserved.