柱状V2O5/AC中V2O5的分布特征对烟气脱硫活性的影响

V_2O_5 Distribution in Cylindrical V_2O_5/AC Pellets and Its Effect on SO_2 Removal from Flue Gas

采用过量浸渍(XS)、等体积浸渍(PV)和半等体积浸渍(HPV)方法,分别制得3种柱状V2O5/AC催化剂,并对其脱硫能力进行评价.结果表明:尽管这3种方法制取的催化剂总w(V2O5)相同(均为0.5%),但V2O5在柱状颗粒中的分布差异却很大;其中半等体积浸渍法制备的催化剂外层w(V2O5)最高,等体积浸渍法的w(V2O5)居中,过量浸渍法的w(V2O5)最低.脱硫前期,催化剂外层的w(V2O5)对脱硫活性的影响很大,外层w(V2O5)高的催化剂脱硫活性较高;脱硫后期,催化剂外层w(V2O5)对脱硫活性的影响变小,而内层w(V2O5)的影响变大,内层w(V2O5)高的催化剂脱硫活性较高.

V2O5/AC pellets with the same V2O5 loading were prepared by an excess solution impregnation （XS）, pore volume impregnation （PV） and half of the pore volume impregnation （ HPV）, respectively. Although the total V2O5 content of three types of pellets is equal （e. g. all being 0,5% ）, the V2O5 distribution in the cylindrical pellets are quite different. V2O5 content of out surface prepared by HPV is highest in three V2O5/AC pellets prepared by different impregnations, and that prepared by XS is lowest and that by PV is medium. S distributions of the three V2O5/AC pellets subjected to SO2 removal for different time. The results show that the one with a high V2O5 content in its outer surface shows a high initial SO2 removal activity, while the one with a high V2O5 content in its center shows a high SO2 removal activity in the later stage.