Correlation of Graphite Flotation and Gas Holdup in Saline Solutions

摘要

Two-phase (solution-air) batch gas holdup tests were undertaken in a laboratory bubble column with six inorganic salts (KCl, NaCl, Na_2SO_4, MgCl_2, CaCl_2, MgSO_4). The electrolytes grouped according to the gas holdup: salts containing divalent ions (1-2,2-1 and 2-2 cation-anion pair) increased gas holdup at lower molar concentrations than salts containing monovalent ions (1-1 salts) and a dependence on ionic strength was demonstrated. The gas holdup was shown to correlate with the graphite flotation results of Pugh et al. (1997). In the presence of coalescence inhibiting salts, gas dispersion appears to play a significant role in dictating flotation performance.