Presented at the 1983 Pittsburgh Conference
THE ANALYSIS OF FLAMMABLE INDUSTRIAL WASTES
USING ION CHROMATOGRAPHY
|David G. Gossman
David Gossman and Craig Cape are now both with Gossman Consulting, Inc.
Industrial wastes consist of complex mixtures of a large variety of compounds that need careful and thorough analysis if they are to be handled safely and disposed properly. In particular the existence of chlorine, bromine, fluorine, and sulphur in these wastes can greatly affect the conditions necessary for safe disposal by incineration or similar methods. Ion chromatography has proven to be a fast reliable method for determining the concentration of these constituents in industrial wastes.
The samples are prepared by using a bomb calorimeter to oxidize the sample and release the ions to be determined. These ions are absorbed into an aqueous wash contained in the bottom of the bomb cylinder. The cylinder is then opened and thoroughly rinsed using enough additional wash to total a prescribed dilution. This aqueous wash is then analyzed using traditional ion chromatography techniques. In these experiments, two ion chromatographs were used. The first wast a Wescan System 10 ion chromatograph. The second was a hybrid system using a Wescan conductivity detector and a Perkin-Elmer Series 2 HPLC pumping system. In both cases, a Vydac anion chromatography column from the Separations Group was used.
Fluorine, chlorine, and bromine are all seen in their free ionic form (Cl-, Fl-, and Br-). Sulphur is found as the sulphate. Other species that may be determined include phosphorous as the phosphate and nitrogen as either the nitrate, nitrite, cyanide, or some combination thereof. Excellent results have been obtained on samples containing between 0.1 percent and 5 percent sulphur, chlorine, or fluorine. Samples containing nitrogen are still being investigated.
By using a computer for data reduction and analysis, the complete analysis, including sample preparation, standardization and data analysis can be completed in less than 30 minutes.