A versatile green analytical method for determining chlorine and sulfur in cereals and legumes.

A versatile, rapid and safe green method for chlorine and sulfur determination using ion chromatography in cereals and legumes was developed. Microwave-induced combustion was evaluated for sample preparation. Ultrapure water and alkaline solutions were assessed for absorption of the analytes. Water was selected because good recoveries (97-109%) were obtained for both analytes. Low consumption of reagents and small quantities of waste are two important advantages of the proposed method. Accuracy was evaluated by analysis of a standard reference material, which agreed with certified values (91-101%). The results for repeatability (RSDs ≤ 4%) and intermediate precision (RSDs ≤ 7%) prove the good precision of the proposed method. Limits of quantification were 16 and 17 mg kg-1 for Cl and S, respectively. Concentrations of Cl and S varied across a wide range (Cl: 35-930 mg kg-1; S: 678-5124 mg kg-1) for 34 samples analyzed, which were, for most of the results, close to the values found in the literature.