Simultaneous Determination of PMS, PDS, and H2O2 Concentrations with Multi-Step Iodometry

Peroxodisulfate (PDS), peroxymonosulfate (PMS), and hydrogen peroxide (H2O2) might coexist in a persulfate system. It leads to the mutual interference concentration determination due their similar structures. Simultaneous detection of three peroxides involves limited reporting. Herein, multi-step iodometry was established simultaneously determine concentrations PDS, PMS, H2O2 coexisting solution. Firstly, molybdate–NaHCO3-buffered proposed uplift overall since recovery rate unexpectedly lower mixture than single solution with reported NaHCO3-buffered iodometry. Then, based on using combination catalase revised acetate-buffered (pH 3). The determined 95–105% standard deviation ≤7% two replicates at individual centration 13–500 μmol∙L−1. rates were within pH 3–11 90–110% presence Cl− (0–150 mg∙L−1), F− (0–1.5 SO42− or NO3− (0–20 mg∙L−1). lowered down 91% 87% sample containing 100 mg/L Ca2+ Mg2+, respectively, but lifted up 100% 93% once pretreated by adding 0.11–1.06 g∙L−1 Na2CO3. In background tap water, surface ground all detected 90–110%, which indicates applicability real waters.