Effect of Ce and La on the activity of CuO/ZSM-5 and MnOx/ZSM-5 composites for elemental mercury removal at low temperature

- CuO/ZSM-5 and MnOx/ZSM-5 composites were modified with Ce and La using citric acid method.
- The effects of temperature, CeO2 content, and La2O3 content on mercury removal performance were examined.
- The mechanism of Hg0 adsorption on CuO-based and MnOx-based sorbents at N2 atmosphere was discussed.

CuO-based and MnOx-based sorbents modified with Ce and La using sol-gel method, were employed for elemental mercury removal at 120-240 °C. The Hg0 removal activity of Mn2O3/ZSM-5 can be significantly enhanced by doping 50 at.% Ce or 10 at.% La, the Hg0 removal efficiency increased by 94% and 71%, respectively. The Hg0 removal ability of CuO/ZSM-5 subtly improved by addition of 50 at.% Ce or 10 at.% La, the Hg0 removal efficiency ascended only by 6% and 18%, respectively. The XPS results revealed that Hg0 transformed to HgO, and CuO (or Mn2O3) was reduced to Cu2O (or Mn3O4), which is in agreement with Mars-Maessen mechanism.

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