[Determination of trace anions in G2-grade phosphoric acid using two-dimensional ion-exclusion-ion-exchange chromatography with valve-switching technology].

This study established a method for determining trace anions in G2-grade phosphoric acid under ultra-clean conditions that used two-dimensional ion-exclusion-ion-exchange chromatography coupled with valve-switching technology. The optimal flow rate of ultrapure water through the ion-exclusion column in the first dimension was determined to be 0.5 mL/min through comparative experiments.