Carbon on Catalysts by Induction Furnace Combustion and Infrared Detection

This method is for determining total carbon on catalysts and in other inorganic materials using a high temperature induction furnace analyzer. The method is generally applied over a range of 0.01 to 20 mass-% carbon; however, up to 100 mass-% carbon can be determined with appropriate calibration. On used catalyst, the carbon may be present as coke and/or hydrocarbons. If only the carbon present as coke is desired, hydrocarbons are removed by extraction prior to analysis, as described in UOP Method 602. Analysis of catalysts containing light hydrocarbons can be problematic due to thermal loss of the hydrocarbons before controlled combustion occurs. For such materials, other methods, such as carbon, hydrogen and nitrogen by ASTM D 5291, should be utilized. The presence of halogens in the sample has been shown to cause corrosion damage to the instrument, therefore a trap consisting of antimony metal and potassium iodide must be utilized.

Analyzers that utilize combustion tube, rather than induction furnace technology may be used if it can be proven they yield precision data at least as good as that listed herein.