Measurement and analysis of H2 and O2 bubbles diameter produced by electroflotation processes in a modified Partridge-Smith cell

Abstract

Diameter and distribution of the bubbles generated by water electrolysis are of vital importance in the electroflotation process of fine particles. It is well known that these parameters influence the efficiency of the flotation process because they affect the collision, adhesion, and transport mechanisms. Moreover, the smaller the bubble diameter, the better the recovery of fines due to the larger surface area of the bubble. Thus, the aim of this work was to evaluate the influence of some of these parameters on the diameter and distribution of hydrogen and oxygen bubbles, produced by electroflotation. A modified Partridge–Smith binary cell with platinum electrodes was used. The system pH, current density, electrolyte concentration, and electrode mesh spacing were evaluated. The results showed that the increase in the pH of the system produced two opposite behaviours in the diameters of hydrogen and oxygen bubbles. The diameter of the hydrogen bubbles decreased, whilst that of the oxygen bubbles increased. The increase in current density and electrolyte concentration caused a decrease in the diameter of the hydrogen and oxygen bubbles. Finally, the increase in the wire diameter and electrode mesh spacing caused an increase in the diameter of hydrogen and oxygen bubbles.