Subscriber access provided by University of Sussex Library
Article
Regenerable sorbent with high capacity for elemental mercury removal and recycling from the simulated flue gas at low temperature Zan Qu, Jiangkun Xie, Haomiao Xu, Wanmiao Chen, and Naiqiang Yan Energy Fuels, Just Accepted Manuscript • DOI: 10.1021/acs.energyfuels.5b00868 • Publication Date (Web): 24 Aug 2015 Downloaded from http://pubs.acs.org on September 9, 2015
Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.
Energy & Fuels is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.
Page 1 of 31
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Energy & Fuels
Regenerable sorbent with high capacity for elemental mercury removal and recycling from the simulated flue gas at low temperature Zan Qu, Jiangkun Xie, Haomiao Xu, Wanmiao Chen, and Naiqiang Yan∗ School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China ABSTRACT: In order to remove and recycle elemental mercury from flue gas, a serial of Ce-Mn binary metal oxides were prepared and tested as the regenerable sorbents for mercury capture. Ce0.5Mn0.5Oy showed the best performance at 100 oC (about 5.6 mg⋅g-1 adsorption capacity) and Ce-Mn binary metal oxides could adsorb more elemental mercury than MnOy can do. Furthermore, it was found that the captured mercury can be released from the sorbent in form of elemental mercury by heating up to 350 oC. Meanwhile, the sorbent can be regenerated and repeatedly used. Powder X-ray diffractometer (PXRD), transmission electron microscopy (TEM), H2-temperature programed reduction (H2-TPR), NH3-temperature programmed desorption (NH3-TPD), X-ray photoelectron spectroscopy (XPS) and N2-adsorption methods were employed to characterize the sorbents. A model based on Hg-TPD data was built to calculate mercury desorption activation energy from the sorbent. Additionally, the impacts of temperature and flue gas components on the adsorption capacity were investigated, respectively. NO had negligible impact on mercury adsorption, while the presence of SO2 slightly inhibited the sorbents’ capability for mercury capture. The results indicated that Ce-Mn binary metal oxides are a promising sorbent for the mercury removal and recycling from flue gas.
∗
Corresponding author, E-mail address:
[email protected] ACS Paragon Plus Environment
Energy & Fuels
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
1. INTRODUCTION Mercury is one of the most hazardous pollutants due to its neurological toxicity, bioaccumulation and persistence.1 With the agreement of Minamata Convention on Mercury in 2013, the emission of mercury from coal-fired power plants has become a serious concern in China.2,3 Recently, the revised emission standard of air pollutants for thermal power plants of China has come into force, in which the limited value of mercury emission has been capped. Mercury emission control will be the trend for the coal-fired power plants. To date, the main technologies for mercury emission control fall into two groups: powder activated carbon (PAC) injection; co-benefit of selective catalytic reduction (SCR) and wet flue gas desulfurization (W-FGD) system (Hg0 was catalytically oxidized into Hg2+ on SCR catalyst and then scavenged by W-FGD).4-8 However, the co-benefit of SCR and W-FGD will drive the mercury from gas phase to liquid or solid phase which may cause the secondary pollution.9,10 PAC displays high efficiency for mercury removal, but the regenerating AC sorbents for further Hg capture is not an effective process which limits its wide application.11 Meanwhile, the commercial value of the fly ash is sacrificed by PAC injection method.12 Therefore, the development of novel non-carbon sorbent with high mercury adsorption capacity and facile regeneration ability has attracted more and more attention.13-15 Especially, developing high performance sorbents for mercury capture downstream the electrostatic precipitator (ESP) or fabric filter (FF) at low temperture (
