Experimental Study on the Mercury Removal of a H₂S-Modified Fe₂O₃ Adsorbent

Abstract

Owing to the massive mercury emission from coalfired power plants and other nonpower industries worldwide, it is imperative to develop non-carbon-based adsorbents for mercury removal. In this work, an efficient sulfur-loaded Fe 2 O 3 adsorbent for mercury removal was developed by H 2 S modification. The optimum modification parameters were determined at the vulcanization temperature of 200 °C and the vulcanization time of 2 h. The effect of reaction temperature and initial mercury concentration on mercury removal was investigated. Through the fixed-bed experiment, it was found that the adsorbent exhibits good mercury removal performance. The mechanism of mercury adsorption was deeply studied based on the characterization analyses of Brunauer−Emmett−Teller (BET), scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetry (TG), and X-ray photoelectron spectroscopy (XPS). The results show that the abundant and well-dispersed active sulfur sites on the surface of samples could enhance the chemical bonding to Hg 0 . The interaction between gaseous H 2 S and Fe 2 O 3 could lead to the formation of active S ad and FeS x (FeS, FeS 2 ) during the modification process. Those active sulfur species can further boost the adsorption and oxidation of Hg 0 to HgS during the mercury adsorption process.

Graphitic Carbon Nitride for Gaseous Mercury Emission Control: A Review

“…Metal sulfides can be attained by reprocessing of mining wastes or sulfide-bearing ores, contributing to their relatively lower costs . In addition, metal sulfides can be attained by sulfidation of metal oxides using exhaust H 2 S at low or middle temperatures, which can also lower the costs of metal sulfide adsorbents. − More importantly, the good thermal stability of most metal sulfides can not only favor the utilization of fly ash but can also restrain mercury methylation . During the mercury capture process, Hg 0 vapor is transferred into stable mercuric sulfide (HgS) with extremely low solubility, warranting the lowest possibility of mercury leaching .…”

Chemical and Process Engineering

“…In this case, the activated surface sulfur reacts with gas phase Hg(0) to create stable HgS. Consequently, there are some proposed Equations from ( 69) to (71) (An et al, 2023;Wu et al, 2021;Xing et al, 2022;Xue et al, 2015): the MnO 2 sorbent. The effectiveness of Hg(0) capture was increased from 82.3% to 90.5%, when the temperature was increased from 80 • C to 160 • C, in the 400 ppm H 2 S gas solution in N 2 .…”

Favorably adjusting the pore characteristics of copper sulfide by template regulation for vapor-phase elemental mercury immobilization

“…Mercury (Hg), a pollutant widely known for its transportability and hypertoxicity, causes persistent contaminations in the ecosystem and has fatal effects on humans aer being emitted into the immediate environment. [1][2][3][4][5] According to the updated Global Mercury Assessment released by the United Nations Environment Programme (UNEP) in 2018, the anthropogenic Hg emission worldwide reached approximately 2500 tons annually, increasing by more than 20% within ve years. 6,7 Among various forms of Hg released from anthropogenic activities (e.g., burning coal, incinerating wastes, smelting ores, and so on), oxidized mercury (Hg 2+ ) and particulate-bound mercury (Hg p ) can be effectively removed during the ue gas treatment process by air pollutant control devices (APCDs).…”

“…[11][12][13] Thus, to adequately fulll the obligations imposed by the Minamata Convention on Mercury and effectively mitigate anthropogenic Hg pollution, it is necessary to propose a pertinent solution to efficiently capture Hg 0 from industrial ue gases. 1,9 Metal suldes (MSs), with surfaces covered by abundant sulfur ligands, and an ability to convert Hg 0 into ultra-stable mercury sulde (HgS), were recently developed and are regarded as potential alternatives to traditional sorbents (e.g., activated carbons) for the Hg 0 removal from industrial ue gases. [14][15][16][17][18] Within the MSs community, copper sulde (CuS) was found to be the most effective Hg 0 remediator as its surface undergoes reconstruction at an ambient temperature, which enriches the CuS surface with coordinatively unsaturated suldes.…”

“…11–13 Thus, to adequately fulfill the obligations imposed by the Minamata Convention on Mercury and effectively mitigate anthropogenic Hg pollution, it is necessary to propose a pertinent solution to efficiently capture Hg 0 from industrial flue gases. 1,9…”