DEVELOPMENT OF KOH ACTIVATED HIGH-SURFACE-AREA CARBON AND ITS APPLICATION TO DRINKING-WATER PURIFICATION

High-surface-area (over 3000 m(2) g(-1)) active carbon (MAXSORB) was d eveloped from a mixture of petroleum coke and an excess amount of pota ssium hydroxide. A considerable number (0.9-1.6 meq g(-1)) of surface functional groups were found compared to that of typical steam activat ed carbons (0.1-0.2 meq g(-1)). Breakthrough of sodium hypochlorite or chloroform was studied using model drinking water at 25 degrees C, co ntaining about 2 ppm of NaClO or 50 ppb of CHCl3. Regardless of the am ount of surface functional groups, the performance of NaClO decomposit ion for MAXSORB was proportional to the BET surface area and reached a value of two to three times more than the typical steam activated car bon. There was an optimum BET surface area for CHCl3 removal, which wa s improved greatly by removing surface functional groups jy heat treat ment at 700 degrees C. (C) 1997 Elsevier Science Ltd.