Excessive calcium and magnesium levels in the second-stage refined brine
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This post was last edited by sunjl1981 on 2013-1-6 at 23:58. In the ion membrane production process, the parameters of the refined brine are very important; excessive levels of calcium and magnesium in the second-stage refined brine have what effects on the ion membranes? ? What are the consequences of having just one parameter out of limit? ? # + + .
Impurities present in saltwater can disrupt the operation of the electrolyzer. If insoluble impurities enter the electrolysis process, they can clog the diaphragm in the electrolyzer, reduce its permeability, and degrade the performance of the electrolyzer. Impurities such as Ca or Mg readily react with the substances in the electrolyte; for example, Ca reacts with Na2CO3 to form CaCO3, while Mg reacts with NaOH to form Mg(OH)2. These precipitates can block the pores of the alkaline-side membrane, reducing its permeability and preventing the electrolyzer from functioning properly. In electrolyzers using graphite as electrodes, if SO42- is introduced into the electrolyte, it will accelerate the corrosion of the graphite and shorten the lifespan of the electrodes.
Firstly, the effects of calcium and magnesium on the ion membrane are relatively independent: compounds of calcium accumulate in the carboxylate layer of the ion membrane, affecting the membrane’s current efficiency, while compounds of magnesium accumulate on the surface of the sulfonate layer, affecting the membrane’s voltage. Both of them form insoluble compounds with anions such as iodine, silicon, and aluminum, thereby contaminating the membrane