2H2S2O8 + 4NaOH → Na2S2O8 + NaHSO5 + NaHSO4 + 3H2O
Peroxydisulfuric acid react with sodium hydroxide to produce sodium peroxodisulfate, sodium peroxosulfate, sodium bisulfate and water. Peroxydisulfuric acid - concentrated solution. This reaction takes place at a temperature near 0°C .