2.1 Experimental materials
The 13 kinds of AC samples were used in this study. These include 8 kinds of coal-based columnar fresh AC, named F-1~F-8, commonly used in the field of flue gas purification; 1 kind of recycled AC, named C-x, recycled many times in the fluidized bed flue gas purification facility fed by F-1; 3 kinds of recycled AC, named C-10, C-20, C-30, which were F-1 respectively completed 10, 20, 30 denitration-desulfurization-regeneration cycles in the fixed bed flue gas purification simulation device; a kind of reconsolidation AC, which was made from the AC powder produced in the fluidized bed flue gas purification facility and coal tar. All AC samples have a diameter of 9 ± 0.25 mm.