[Evaluation for the regeneration efficiency of activated carbon by wet air oxidation]

It is well known that different regenerating techniques of activated carbon(AC) require the suitable evaluating methods for regeneration efficiency. In this paper, several methods for evaluating the regeneration efficiency of AC were compared and discussed by wet air oxidation(WAO) which were respectively based on different experimental protocols such as iodine value, molasses color adsorption, breckthrough profile, adsorption isotherm and standard reload experiment. The iodine value, molasses color adsorption and breckthrough profile yielded indefinitely PR values for WAO process, so they could not be applied to evaluate regeneration efficiency. And adsorption isotherm experiment was more correct because it compared isotherm loadings at the same equilibrium liquid phase concentrations, but this more laborious and time-consuming method was difficult to be widely used. The results also showed that the standard reload experiment was consequently picked out, easy to use and had high sensibility alternative to adsorption isotherm experiment. When controlling the WAO parameters at 250 degrees C, 0.6 MPa and 1 h, the regeneration efficiency arrived to 55%.