Application of the Sulfur Recovery Method by the Kiba Reagent for the Subsequent Isotope Analysis of Natural Sulfates and Sulfuric Acid

A simple and reliable method for sulfate reduction using the Kiba reagent is adapted for the preparation of trace amounts of natural sulfates and sulfuric acid for isotopic (δ34S, δ33S and δ36S) sulfur analysis. It is shown that the method is successfully applicable for the preparation of samples of sulfates and sulfuric acid with a sulfur content of 0.1 mg for isotopic analysis of 34S, 33S, and 36S isotopes. The accuracy of δ34S determination in natural sulfates was ±0.3‰, the accuracy of δ34S, ∆33S, and ∆36S measurement in sulfuric acid was ±0.5, ±0.027, and ±0.38‰, respectively.