Infrared thermography: A new approach for the characterization and management of activated carbons applied in water treatment

Abstract

A new non-invasive methodology based on infrared thermography (IRT) to evaluate the exhaustion level of granular activated carbon (GAC) at different depths of a target industrial water treatment filter is studied. IRT results are discussed in terms of adsorption capacity and correlated with dedicated analytical methods: N2 gas adsorption, TGA, TD-GC/MS and NMR. Findings revealed that the surface temperature and surface thermal density parameters are contingent with the exhaustion level as well as the surface area and pore volumes of the GAC samples. Surface temperature decreased with 80% and the surface thermal density with 35% comparing exhausted Top-GAC and virgin GAC. Linear correlation was found between IRT parameters and the exhaustion profile of 98%. During GAC exploitation the surface area was reduced to 85% and the total volume of pore to 80%. The IRT method demonstrated to be simple and accurate and suitable for GAC management of water treatment.