AN ANALYZER FOR DYNAMIC MICRODETERMINATION OF CARBON HYDROGEN NITROGEN SULFUR AND OXYGEN

An apparatus is described for the microdetermination of carbon, hydrogen, nitrogen, sulfur, and oxygen. The technique is based on the uncatalyzed, dynamic, flash-combustion of the sample in an oxygen/helium atmosphere at 1060-1080 °C in a quartz tube. Retention and separation of the combustion gases, NO2, CO2, SO2, and H2O, are accomplished by using chromatographic columns in liquid nitrogen. Measurement is by thermal conductivity. The precision and accuracy of the carbon, hydrogen, and nitrogen analyses are comparable with those obtained with commercial analyzers and classical methods. The preliminary results for sulfur are encouraging. A C, H, N, and S analysis requires 16 minutes. With carbon in the combustion tube at 1120°C, oxygen can be determined in 9 minutes as carbon monoxide, with no change in trapping, separation, or measurement. The precision and accuracy are equal to those obtained with slower pyrolysis methods. © 1969, American Chemical Society. All rights reserved.