Simultaneous determination of three chloroacetic acids,three herbicides,and 12 anions in water by ion chromatography

An ion chromatography method was developed for the simultaneous detection of three soluble herbicides (glyphosate, bentazone and picloram), three chlorine disinfection byproducts (monochloroacetic acid, dichloroacetic acid and trichloroacetic acid) and 12 anions in water (Cl^–, Br^–, SO₄^2–, CO₃^2–, ClO₃^–, ClO₄^–, BrO₃^–, PO₄^3–, NO₂^–, NO₃^–, CH₃COO^– and COO^–). High linearity (r² > 0.996) was observed for all target analytes for each respective concentration range. The limit of detection and limit of quantitation were between 0.21–0.85 and 0.06–25.46 μg/L, respectively. However, the interference effect of Cl^–, NO₃^–, SO₄^2– and CO₃^2– on some target analytes must be considered during the analysis. Sample pre‐treatment by a hydrogen column (H‐column) required to reduce the negative effect of CO₃^2–. Additionally, sample pre‐treatment by a sliver–hydrogen column (Ag–H‐column) is required when Cl^– > 100 mg/L and SO₄^2– < 50 mg/L, and pre‐treatment by both a barium column (Ba‐column) and an H‐column is required when Cl^– > 100 mg/L and SO₄^2– > 50 mg/L. When Cl^– > 100 mg/L, SO₄^2– > 50 mg/L and CO₃^2– > 20 mg/L, the sample pre‐treatment by either an Ag–H–Ba‐column or an Ag–H‐column and Ba‐column is required to minimize interference.