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Show He, Og), sulfur and nitrogen pollutants (HoS, SO2, CuS, CS2, hCN, NH3, and NO,), and elemental analysis of coal and char (C, H, N, S, 0 {by difference) , and ash). Permanent Gases. A Hewlett Packard Model 5830 gas chromatograph, with a mixture of 10% hydrogen in helium as a carrier gas and equipped with a Poropak column in a series-parallel arrangement with a molecular sieve column, was used to measure the gases CH4 and CQ2, 0-, Ar, H2 N2, CH^, and CO. Temperature programming and adjustment of the series-parallel switching mode was required to detect hydrogen and completely separate oxygen and argon. Helium was measured, when needed, on a Tracer Model MT 150 gas chromatograph. Commercial standard gases were used to determine the accuracy of the permanent gas methods. Close agreement was obtained between the external standard values and the experimental percentages of each component gas. Comparison between the standard gas results and the measured results indicated the accuracy obtained from the current method of gas analysis by gas chromatography. The accuracy (standard deviation) was less than + 1.65 percent for all gases except nitgrogen, which was + 3.3 percent. Gaseous Sulfur Species. Sulfur pollutant gases were measured on an HP-5735A gas chromatograph equipped with a flame photometric detector. The sulfur gases were separated on a 2.7 m x 32 mm teflon Chromosil 310 column using a temperature program which ensured complete separation of all sulfur gas components regardless of their relative amounts in the gas. Nitrogen was used as the carrier gas. Repeatability and accuracy were tested against known commercial standards of each specific sulfur gas. These results are reported in detail by Highsmith (12) and Burkinshaw (13). The accuracy (standard deviation) was estimated to be between +1.5 and 2 percent. Gaseous Nitrogen Pollutants. Only small amounts of NH3 and HCN were expected in the gas phase, the major portion being dissolved in the probe quench-water. For the gas, the less accurate Drager tube method was sufficient. The use of Drager tubes and the accuracy of analysis of this technique is described by Price (4). Samples were collected in plastic sample bags and eluted with a syringe into a Drager tube which was 6-6 |