Ion Chromatography and the Certification of Standard Reference Materials

Ion chromatography is used extensively at the National Institute of Standards and Technology for the analysis of Standard Reference Materials. At present, the primary emphasis is on the determination of the nonmetals, especially sulfur and chlorine. Procedures have been developed and instrumentation adapted to improve the accuracy and precision of the technique. Sample preparation is a critical component of the analytical procedure. For combustible materials, the preferred method of sample preparation involves the use of a high-pressure oxygen bomb. The types of materials analyzed include fuels, botanicals, biologicals, and rainwater.