Removal of Elemental Mercury from Flue Gas Using Cobalt-Containing Biomaterial Carbon Prepared from Contaminated Iris sibirica Biomass

Yuan Wang; Honghu Li; Zhong He; Jianmin Guan; Kaikai Qian; Jiangjun Hu

doi:10.1021/acsomega.9b03605

Removal of Elemental Mercury from Flue Gas Using Cobalt-Containing Biomaterial Carbon Prepared from Contaminated Iris sibirica Biomass

ACS Omega. 2020 Mar 17;5(12):6288-6298. doi: 10.1021/acsomega.9b03605. eCollection 2020 Mar 31.

Authors

Yuan Wang¹, Honghu Li², Zhong He¹, Jianmin Guan¹, Kaikai Qian¹, Jiangjun Hu¹

Affiliations

¹ School of Resource and Environmental Sciences, Wuhan University, Wuhan, Hubei 430079, PR China.
² School of Information and Safety Engineering, Zhongnan University of Economics and Law, Wuhan, Hubei 430073, PR China.

Abstract

Iris sibirica biomass (ISBM) used for cobalt (Co) pollution remediation was prepared by one-step pyrolysis and employed to remove elemental mercury (Hg⁰) from flue gas. Results showed that the ISBM pyrolyzed at 700 °C (ISBM700) exhibited good Hg⁰ removal performance (about 86%) at 150 °C. The existence of NO and O₂ facilitated the removal of Hg⁰, while SO₂ and water vapor inhibited it. Characterization analysis (including N₂ adsorption-desorption, X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectrometry) showed that ISBM700 has a relatively higher specific surface area, a quantity of lattice oxygen derived from well-dispersed amorphous-phase CoO _x , and abundant oxygen functional groups. A Mars-Maessen mechanism is thought to be involved in the Hg⁰ removal process. The adsorbed Hg⁰ could be oxidized to HgO by the surface oxygen species derived from CoO _x , and then, the consumed surface oxygen species can be replenished by O₂. Therefore, the Co-contaminated I. sibirica biomass (CCIB) from phytoremediation could be utilized for Hg⁰ removal after being pyrolyzed instead of any chemical modification.