Studies On The Catalytic Performance Of Modified Activated Carbon In The Regeneration Of Hexamminecobalt(Ⅱ)

The aqueous ammonia can be taken to de-NO and de-SO2from flue gases simultaneously by adding soluble Cobalt(II) salt into ammonia solution. However the [Co(NH3)6]2+which formed by adding soluble Cobalt(II) salt into aqueous ammonia solution can be oxidized to [Co(NH3)6]3+by the oxygen in the flue gases during the absorb process. While [Co(NH3)6]3+could not bind NO nor can activate oxygen. Activated carbon can be used to regenerate hexammineclbalt(II) as a catalyst, then the process of de-no would be a continuous process.In this paper, KOH, NaOH and K2S2O8have been used to modify activated carbon to enhance the catalytic performance of activated carbon in the regeneration of hexanninecobalt (II). The effort of different preparation variables on the final catalytic performance of activat-ed carbon were discussed,such as mixing ratio, heating temperature and activation time were investigated when KOH and NaOH were been used to modify activated carbon,while the impregnated temperature, impregnated concentration,impregnated duration and activation were considered when activated carbon modified by K2S2O8solution. FT-IR, BET, FSEM, Boehm titration, XPS, Elemental analysis has been taken to anslysis the efforts of the physical structure and surface chemical property of activated carbon on its’catalyst performance.The bacth stirred experiments show that when activated carbon was treated in follow conditions:the ratio of activated carbon mixing with KOH is1to3in mass, activated in700℃for3hours,The catalytic performance of activated carbon has been improved immensely. When actitivated carbon treate as follows:the mass ratio of AC/NaOH is1:3, activated in600℃for6h, the modified activated show the most catalytic performance.When NaOH used as modification agent. Impregnated in0.3mol/L K2S2O8solution for9hours, keep the temperatue of solution in40℃seem to be the most effective modification when K2S2O8was taken as an modification method.The chemical analysis show that KOH,NaOH and K2S2O8modified activated carbon content more acid function groups,while basic function group decreased. Lactonic which benefit to the catalytic performance of activated was enhanced a lot, especially for K2S2O8modified activated cabon, which surface area was decresed after modification. While BET analysis proved that the surface enlarged immensely when activated carbon modified by KOH and NaOH.The modified carbon can improve the catalytic perpormance of coconut activated carbon in the experiment of de-SO2and de-NO simultaneous with [Co(NH3)6]2+ammonia solution.