CARBON REGENERATION - DEPENDENCE ON TIME AND TEMPERATURE

The time and temperature of regeneration were examined in a bench-scale study using granular activated carbon (GAC) that had been loaded in a treatment plant and a laboratory. The rate of regeneration was constant at a given temperature for time periods up to 30 min and increased exponentially with increasing temperature. The reactivity of the base carbon was important in determining the proper time and temperature for regeneration. For coal-based GAC loaded with naturally occurring organic material and methylene blue, GAC capacity was returned to that of virgin carbon at a temperature of 850-degrees-C in 15 min. Shorter times and lower temperatures resulted in a loss of adsorption capacity. Longer times resulted in increased capacity for large molecules but the same or reduced capacity for small adsorbates.