Activated Carbon Of Low-temperature Catalytic Oxidative Regeneration Methods

Thermal regeneration is the main regeneration method of activated carbon (AC) in the world at present, but it need high temperature, and its weight loss and burned loss are seriously. Catalytic oxidative regeneration is an new method debased on thermal regeneration, This paper has studied catalytic oxidative regeneration of granule activated carbon(GAC) and powder activated carbon (PAC) saturated with phenol.CuO was employed as catalyst, and loaded on AC by equal volume impregnation, the optimal burned conditions were determined by experiments. The samples were examined by the adsorption isotherms, and the most promising catalyst was found to be the sample containing 2% CuO (calculated as weight). Experimental data indicated that the adsorption ability was changed, the temperature of phenol oxidation(Tp), temperature of AC surface oxidation(Tc) and skeleton oxidation(Tg) were all reduced at the same time. The range between Tp and Tc was the regeneration temperature of AC which given by the thermal analysis experiments. The optimal regeneration conditions were searched in the range and regeneration effects of GAC and PAC were studied at last.Study on regeneration shows that GAC was regenerated at 250℃, the first regeneration efficiency was 78%, and 53.2% after six repeated regeneration experiments. PAC was regenerated at 240℃, the first regeneration efficiency was 99.9%, and 99.2% after nine repeated regeneration experiments ,and the average weight loss was 2.0%. So the regeneration efficiency of PAC was superior to GAC.Experiments of SEM, surface area, ICP, XRD were done with the PAC samples. The results showed that catalyst could be housed only in the mesopores and macropores, so some pores were blocked up and the surface area was reduced. The adsorption capacity was increased because of the action of catalyst at the low metal weight, while it was reduced because of the reduction of surface area at the high metal weight.