Simultaneous Anodic and Cathodic Production of Sodium Percarbonate in Aqueous Solution

Sodium percarbonate (SPC) can be produced electrochemically from aqueous Na 2 CO 3 solution in both its 2Na 2 CO 3 ·3H 2 O 2 and Na 2 C 2 O 6 forms simultaneously. This was achieved in a two-compartment cell separated by a cation-exchange membrane. Na 2 C 2 O 6 was produced on the anodic side by water oxidation on a boron-doped diamond electrode, with anodic current efficiencies of 20-40%. On the cathodic side, SPC was synthesized from carbonate through generation of H 2 O 2 by oxygen reduction on high-surface-area carbon felt. Cathodic current efficiency was 60% and nearly constant. The effect of Na 2 SiO 3 as a percarbonate stabilizer was studied during electrolysis and during storage, with 4 g/L giving the best performance.