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Technical Report 
Flame Photometric Detector. The Application of a Specific Detector for Phosphorus and for Sulfur Compounds Sensitive to Subnanogram Quantities 
Brody, SS; Chaney, JE 
pages 42 
A flame photometric detector was developed for gas chromatographic analysis of organophosphorus compounds in the parts per billion range and organosulfur compounds in the parts per million (ppm) range. Samples of at least 1 microliter were injected into a hydrogen rich flame, and the light from the flame emission was passed through interference filters having a maximum transmittance of 526 millimicrons for phosphorus determination or 394 millimicrons for sulfur analysis. The flame was shielded in a manner that blocked emissions of similar wavelength for compounds not containing phosphorus or sulfur. Response peak heights were measured at a photomultiplier voltage of 750 volts. The sensitivity of the detector was tested by measuring response peaks at 526 millimicrons for 0.0063 to 63.0ppm parathion and 0.0062 to 62.0ppm malathion, and at 394 millimicrons for 0.63 to 126.0ppm parathion and 0.62 to 123.0ppm malathion. The specificity of phosphorus detection was assessed by analyzing a mixture of 0.25ppm triethyl-phosphate (78400) and 250 to 325ppm dibutyl-phthalate (84742), benzophenone, (119619), p-nitroacetophenone (100196), 1,2,4-trichlorobenzene (120821), and hexachlorobutadiene (87683). The detector's features were compared to those of the original German device. The instrument readily detected phosphorus compounds at 0.0062ppm and sulfur compounds at 0.62ppm. Response peak heights were linear over 4 decades of phosphorus concentrations, and nearly linear over 2.2 decades of sulfur concentration. At 526 millimicrons, 0.25ppm triethyl-phosphate gave almost a full scale peak, while 250 to 325ppm of nonphosphate compounds were undetectable. The detector improved on the original German design by being more sensitive, compact, and adaptable, using a metal burner assembly in place of quartz, halving operational air flow to 200 milliliters per minute, and not requiring water cooling, an afterburner, a drain for liquid condensation, or optical realignment between phosphorus and sulfur determinations. 
DCN-118782; Flame ionization methods; Analytical instruments; Thermal reactions; Trace analysis; Testing equipment; Detectors; Phosphorus compounds; Sulfur compounds; Gas chromatography