ASTM D5373

Determination of the Total Carbon, Hydrogen, and Nitrogen in Organic Matrices

Applicability: This procedure applies to all samples received and analyzed at Conti Testing Laboratories, Inc. (CTL), Pittsburgh, Pennsylvania for total carbon, hydrogen, and nitrogen in coal, coke, alternative fuels, oils, and other solids/liquids, by combustion furnace.

Purpose: Carbon, hydrogen, and nitrogen are determined concurrently in a single instrumental procedure. The quantitative conversion of the elements into their corresponding gases (CO2, H2O, and NOx) occurs during combustion of the sample, at an elevated temperature in an atmosphere of oxygen. Combustion products, which can interfere with the subsequent gas analysis, are removed. Oxides of nitrogen (NOx) are reduced to N2 before detection. The carbon dioxide, water vapor, and elemental nitrogen in the gas stream, are determined by appropriate instrumental detection procedures.