SIMULTANEOUS MICRODETERMINATION OF CHLORINE, BROMINE AND PHOSPHORUS IN ORGANIC-COMPOUNDS BY ION CHROMATOGRAPHY

A procedure far the simultaneous microdetermination of chlorine, bromi ne and phosphorus in organic compounds is described. It consists of io n chromatographic analysis, after suitable dilution, of the solution r esulting from the collection in water containing hydrogen peroxide of the combustion products obtained by decomposition of the sample in a S choniger hash. Before analysis, this solution undergoes a post-combust ion procedure involving further hydrolysis of the combustion products which allows a nearly quantitative recovery of phosphorus to be achiev ed even in the presence of other heteroatoms such as chlorine and brom ine. This post-combustion step avoids negative errors in the microdete rmination of phosphorus by ion chromatography owing to the minor but n ot insignificant amounts of both pyrophosphate and a cyclic metaphosph ate which are formed together with the predominant orthophosphate in t he conventional Schoniger combustion of organophosphorus compounds. Th e accuracy and precision of the overall procedure were evaluated.