VOLTAGE AND BUBBLE RELEASE BEHAVIOUR IN A LABORATORY CELL AT LOW ANODE-CATHODE DISTANCE

The bubble release and bubble overvoltage were investigated in a laboratory cell setup. In the experimental set-up industrial anode carbon of a cross-section area of 100x100 mm and a electrolyte of industrial standard composition was used. The anode-cathode distance (ACD) was adjusted between 15 and 40 mm and the current density was mainly varied from 0.80 A/cm2 to 1.1 A/cm2. The experiment showed a basically linear dependence between cell voltage and ACD; down to an ACD of 15 mm. The bubble release improved at low ACD, as indicated by the bandwidth of the cell voltage signal. By means of video equipment, the bubble release frequency recorded in parallel and so allowed for additional interpretation of the bubble release behaviour.