Characterizing the ignition process of activated carbon Original Research Article

Properties of activated carbons at elevated temperature, specifically the spontaneous ignition temperature (SIT) and the point of initial oxidation (PIO), are of great significance in a number of unit operations. Although the SIT and PIO should be evaluated for each individual use, a standard method is required to compare products, insure quality, and optimize processes. Different methods for determining the SIT and PIO are compared using base (BPL, Coconut Shell, and MaxSorb) and impregnated carbons (ASC, ASZM, and ASZM-T). The SIT was determined by the ASTM and thermal analysis (TG and DSC) methods. The PIO was determined by effluent CO2 concentration analysis, thermal analysis (TG and DSC) and temperature profiling. These comparisons show that not all of these methods have general utility, some are not easily correlated, and that there is evidence of the validity of two reaction regimes of interest. The simplest method that provides the most consistent conservative estimate of reaction commencement is measuring the PIO with the temperature profiling technique.