来源：ACS Publications
Alkaline earth metal deposition is a key deactivation issue for Hg0 removal adsorbents in coal-fired flue gas, yet its influence on Co-based adsorbents remains insufficiently understood. In this work, Ca- and Mg-poisoned Ce–Bi–Co adsorbents were prepared by impregnation, solid-state diffusion, and dry mixing to simulate different deposition modes. The effects of metal species, poisoning route, loading level, and SO2 coexistence on Hg0 removal were examined in a fixed-bed reactor. Characterization results showed a uniform distribution of Co, Ce, and Bi and a mesoporous texture, providing a reliable basis for poisoning evaluation. Hg0 removal tests indicated that alkaline earth metal poisoning generally increased the Hg0 breakthrough rate and reduced mercury uptake, with Ca exerting stronger inhibition than Mg. Impregnation caused the most severe deactivation among the three poisoning routes, while dry mixing showed the weakest effect, highlighting the critical role of the contact mode between alkaline earth species and the adsorbent surface. Increasing Ca or Mg loading usually intensified deactivation, whereas low Mg loading caused only mild inhibition or slight promotion under the tested conditions. This behavior is interpreted cautiously as an observed performance trend, possibly related to limited surface disturbance at low Mg loading rather than a directly verified chloride-related pathway. SO2 exhibited a concentration-dependent dual effect. Moderate SO2 partially improved Hg0 removal over the poisoned adsorbents, which may be associated with interactions between SO2-derived species and Ca/Mg-containing deposits. In contrast, excessive SO2 weakened this positive effect, possibly due to sulfur-species accumulation and competition for active surface sites. This work provides comparative evidence for how poisoning route, loading level, and SO2 coexistence influence Ce–Bi–Co deactivation and offers guidance for evaluating poisoning-resistant Hg0 control adsorbents.