OPTIMAL TEMPERATURES FOR CATALYTIC REGENERATION OF ACTIVATED CARBON

Activated carbons impregnated with a mixture of copper(II), iron(III) and chromium(III) oxide catalysts were prepared in order to facilitate catalytic regeneration of AC saturated with phenols. The temperature ranges of phenol oxidation (T-p), carbon oxidation (T-c) and carbon bu rn-off were determined from DTA/TGA investigations in oxidizing and in ert atmospheres. The impregnated catalyst facilitated phenol oxidation but also lowered the T-c of the AC. Catalytic regeneration can be con ducted between T-p (220-240 degrees C) and T-c (320-370 degrees C). Ca talytic regeneration of spent impregnated carbon, at 270 degrees C in flowing air, restored almost all of its initial adsorption capacity an d specific surface area while in the absence of a catalyst the regener ation achieved was only 25-30%. The results obtained from the polyther mic investigations (DTA/TGA) correlate well with those from the regene ration experiments and, therefore, may be used for determination of te mperature conditions for catalytic regeneration of saturated carbons. (C) 1997 Elsevier Science Ltd.