FUEL
·
2016
·
IF 3.611
Shunlin Tang,Lina Wang,Xinbin Feng,Zhaohui Feng,Ruiyang Li,Huipeng Fan,Ke Li
Mercury species distribution in the flue gas from three typical coal-fired power plants have been investigated using a C-5000 sampler for Ontario Hydro Method (OHM) to evaluate specified Hg emission inventories in the largest coal-production province of China, Inner Mongolia. The feed coal, bottom ash, fly ash and gypsum have also been sampled in the field. Mercury emissions are in the dominant form of Hg 0 (>85%). The Hg 2+ (<15%) and the Hg p (<2%) emissions are minor fractions of Hg t in the flue gas. The wet limestone flue gas desulfurization device (WLFGD) showed much higher removal efficiency for Hg 2+ (87–95%) than for the other two Hg species. The input Hg/output Hg varied from 92% to 115% for the tested 3 coal-fried utility boilers during sampling time. We obtained comprehensive Hg discharge factors, including direct atmospheric Hg emission factors and indirect discharge factors of Hg associated with bottom ash, fly ash and gypsum, to the environment, designating the fates of Hg in coal. We estimated the Hg discharges from coal-fired power plants in Inner Mongolia in 2008–2014 and expanded to China. The maximum of direct Hg emissions from coal-fired power plants of Inner Mongolia was 24 Mg in 2012. The Chinese coal-fired power plants emitted directly 100 Mg Hg to the atmosphere every year at the nationwide air control actions. The maximum discharges of Hg associated with fly ash and gypsum of Inner Mongolia was 81 Mg and 11 Mg in 2012, respectively. The national Hg discharges with fly ash and gypsum every year are respectively about 300 Mg and 82 Mg, majority of which may be reemitted to the atmosphere by the utilization industry. Therefore, mercury emissions from coal-fired power plants are not the largest single source of Hg to the atmosphere in normal operation of the current efficient denitrification, particles control and desulfurization devices. Instead, the utilization industry of fly ash and gypsum would be emitting more Hg to the atmosphere.
研究领域:
环境科学
·
能源与动力工程
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2014
·
IF 3.406
Mingyang Sun,Zimo Lou,Guanghuan Cheng,Shams Ali Baig,Li Fang,Xiaoxin Zhou,Yixia Shen,Xinhua Xu
Wet flue gas desulfurization (WFGD) system has been increasingly recognized to be effective in Hg removal. But the generated secondary pollution due to Hg re-emission from desulfurization solutions or solid byproducts has received researchers’ attention. In this paper, the distribution of captured Hg 2+ (L) in the simulated WFGD slurry was studied as a function of various environmental factors. Experimental results indicated that the pH value had a strong effect on Hg 2+ reduction but had negligible influence on the Hg 2+ retention by the grained fraction of gypsum. Increasing in pH value resulted in higher Hg 2+ reduction and over 46% of Hg 2+ was found to be reduced into Hg 0 at pH 5.0. Besides, increased slurry temperature also promoted the Hg 2+ reduction and Hg 0 re-emission as well as the Hg 2+ retention efficiency by gypsum. Other factors including S (IV), Cl − and NO 3 − concentration was found to inhibit Hg 2+ transformation into Hg 0 but slightly promoted the Hg 2+ retained in gypsum. Moreover, the addition of sodium sulfide (Na 2 S), 2,4,6-trimercaptotiazine, trisodium salt nonahydrate (TMT), and sodium dithiocarbamate (DTCR) prevented the Hg 2+ reduction and precipitated out as insoluble HgS, Hg 3 (TMT) 2 and Hg(DTCR) 2 on gypsum. The findings presented in this study could provide theoretical basis for Hg removal in coal-fired power plants.
研究领域:
环境科学
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化学工程
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产品关联
DOI
高影响因子
Nature Food
·
2024
·
IF 23.6
Tang Wenli,Bai Xu,Zhou Yang,Sonne Christian,Wu Mengjie,Lam Su Shiung,Hintelmann Holger,Mitchell Carl P. J.,Johs Alexander,Gu Baohua,Nunes Luís,Liu Cun,Feng Naixian,Yang Sihai,Rinklebe Jörg,Lin Yan,Chen Long,Zhang Yanxu,Yang Yanan,Wang Jiaqi,Li Shouying,Wu Qingru,Ok Yong Sik,Xu Diandou,Li Hong,Zhang Xu-Xiang,Ren Hongqiang,Jiang Guibin,Chai Zhifang,Gao Yuxi,Zhao Jiating,Zhong Huan
Dietary exposure to methylmercury (MeHg) causes irreversible damage to human cognition and is mitigated by photolysis and microbial demethylation of MeHg. Rice ( Oryza sativa L.) has been identified as a major dietary source of MeHg. However, it remains unknown what drives the process within plants for MeHg to make its way from soils to rice and the subsequent human dietary exposure to Hg. Here we report a hidden pathway of MeHg demethylation independent of light and microorganisms in rice plants. This natural pathway is driven by reactive oxygen species generated in vivo, rapidly transforming MeHg to inorganic Hg and then eliminating Hg from plants as gaseous Hg°. MeHg concentrations in rice grains would increase by 2.4- to 4.7-fold without this pathway, which equates to intelligence quotient losses of 0.01–0.51 points per newborn in major rice-consuming countries, corresponding to annual economic losses of US$30.7–84.2 billion globally. This discovered pathway effectively removes Hg from human food webs, playing an important role in exposure mitigation and global Hg cycling.
研究领域:
环境科学
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植物生物学
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毒理学
·
公共卫生
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DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2022
·
IF 4.326
Songyuan Sun,Haomiao Xu,Yurui Fan,Zhisong Liu,Qinyuan Hong,Wenjun Huang,Zan Qu,Naiqiang Yan
The polyvinylchloride industry is an important mercury emission source derived from the decomposition of commercial activated carbon-supported mercuric chloride (HgCl2/AC, with 12–15 wt % HgCl2) in acetylene hydrochlorination. Our results indicated that the loss of mercury was ascribed to the Hg–Cl bond breaking from the HgCl2 molecule at elevated temperatures that resulted in slip Hg0 in the exhausted gas. Herein, we employed a novel strategy that uses chalcogen bonding (ChB, e.g., S-, Se-, and Te-) interactions to anchor HgCl2 molecules, to improve the thermal stability and catalytic performances. The mercury desorption temperature reached approximately 300 °C, which is much higher than the optimum hydrochlorination reaction temperature. Notably, low-mercury catalysts (5 wt % HgCl2) guaranteed high catalytic performances, and Se–HgCl2/AC exhibited 83% acetylene conversion efficiency and near-perfect 100% selectivity. Moreover, the online mercury monitoring results showed that Se–ChB significantly inhibited the escape of mercury during the reaction. Density functional theory results confirmed that the reaction followed an Eley–Rideal (E–R) mechanism, which showed that the strong adsorption of HCl endowed the catalyst with superior durability and facilitated the reaction by reducing the energy barrier from 0.94 to 0.54 eV. Thus, the new strategy for highly stable low-mercury catalyst preparation can solve the problem of mercury contamination and enhance the productivity of PVC production.
研究领域:
化学工程
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环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Yan Du,Jie Yang,Ye Liu,Jiacheng Zhou,Limei Cao,Ji Yang
Mercury is one of the important industrial resources, however, because the Minamata Convention restricts the exploitation of mercury resources, it is necessary to efficiently recycle mercury. In order to realize the resource utilization of mercury, the electrochemical method is used to remove the oxidized mercury in the liquid phase and collect the mercury resources. In this study, a titanium plate was used as a cathode to study the reduction of oxidized mercury. Through electrochemical characterization, it can be determined that the oxidized mercury is finally reduced to Hg 0 . The reduction efficiency of Hg 2+ can reach 90% after 24 h of electrolysis under certain conditions. The effects of reaction time, current density, stirring rate, electrode spacing and initial Hg 2+ concentration on the reduction efficiency were also studied. The optimal conditions can be obtained through research: current density 10 mA/cm 2 , no stirring, electrode spacing 20 mm, and electrolyte concentration 10 mg/L HgSO 4 -10% H 2 SO 4 50 mL. The kinetic analysis shows that this reaction accords with the first-order reaction kinetics.
研究领域:
环境科学
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电化学工程
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产品关联
DOI
高影响因子
ENERGY & FUELS
·
2024
·
IF 5.2
Yuan-Ming Cao,Xue-Lei Duan,Miao Bian,Hou-Yu Wang,Yi-Wen Shen,Chong Gao,Chun-Gang Yuan
The immobilization of Hg0 and detoxication of Hg-containing composites are enormous challenges for Hg pollution control, which provide a high requirement for the design and synthesis of materials. Herein, a new composite with halloysite, selenium, and transition metals as raw materials (FeCo-LDH/HNTs@Se) for a Hg0 trap was designed by precipitation with ion exchange and an in situ selenization method. Intrinsic features such as high affinity, microwave permittivity (109–1012), large surface area, abundant pores, and many active components favored Hg0 removal and immobilization. The removal performance, flue gas tolerance, and synergistic effect of active components were improved greatly when microwave was added. The study indicated that (1) the Hg0 removal efficiency of the composite could reach 99.4%; (2) the composite had excellent tolerance to different industries’ flue gases. The electron exchange of Co(II)/Co(III) and Fe(II)/Fe(III) and the existence of Se and SeO2 were important for Hg0 immobilization. HgSe was the main adsorption product based on both X-ray photoelectron spectroscopy (XPS) and an online lab-built thermal decomposition system (TPD-AFS) analysis, which made the used-materials possess low mercury leaching content (0.09 mg·L–1) lower than the US EPA regulatory value (0.2 mg·L–1). This work provides a sound way for mercury control, which is significant for environmental protection.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2016
·Vol. 92
·期 4
·819-826
·
IF 2.738
Xiao Liang,Ying Ge,Zhenglong Wu,Weidong Qin
BACKGROUND Hg(II) and MeHg(I) are toxic pollutants causing wide concerns. Polyamidoamine-grafted magnetic silica nanoparticles (Fe 3 O 4 -SiO 2 -PAMAMs) were synthesized as beads, on which herring sperm DNA fragments were immobilized as reacting moieties for removal of Hg(II) and MeHg(I) from water matrices. The factors influencing the removal, such as DNA fragments, generation of the polyamidoamine spacers and pH, were studied. Further, the adsorption mechanisms were explored by means of adsorption kinetics and isotherms. RESULTS Assembling DNA fragments on the polyamidoamine-grafted beads promoted sharply the removal of both Hg(II) and MeHg(I). Adsorptions of Hg(II) and MeHg(I) followed pseudo-second-order kinetics; but their adsorption isotherms obeyed Langmuir and Freundlich models, respectively. Under the optimum conditions, the adsorption equilibrium time was approximately 5 min for Hg(II) and 5 s for MeHg(I) with maximum percentage removals of ∼95% and ∼90%, respectively. The adsorbent could be regenerated easily without significant decrease in removal efficiencies. CONCLUSION The Fe 3 O 4 -SiO 2 -PAMAM beads could bind DNA steadily, and the DNA fragments interacted strongly with mercury species. The strategy enabled the water-soluble DNAs to work as efficient removing reagents for rapid and cost-effective removal of Hg(II) and MeHg(I). © 2016 Society of Chemical Industry
研究领域:
环境科学
·
生物化学
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产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2023
·
IF 13.6
Fuyu Xie,Qingke Yuan,Yukang Qie,Ying Meng,Fubo Luan
Methylmercury (MeHg) uptake by demethylating bacteria and inorganic divalent mercury [Hg(II)] uptake by methylating bacteria have been extensively investigated because uptake is the initial step of the intracellular Hg transformation. However, MeHg and Hg(II) uptake by non-methylating/non-demethylating bacteria is overlooked, which may play an important role in the biogeochemical cycling of mercury concerning their ubiquitous presence in the environment. Here we report that Shewanella oneidensis MR-1, a model strain of non-methylating/non-demethylating bacteria, can take up and immobilize MeHg and Hg(II) rapidly without intracellular transformation. In addition, when taken up into MR-1 cells, the intracellular MeHg and Hg(II) were proved to be hardly exported over time. In contrast, adsorbed mercury on cell surface was observed to be easily desorbed or remobilized. Moreover, inactivated MR-1 cells (starved and CCCP-treated) were still capable of taking up nonnegligible amounts of MeHg and Hg(II) over an extended period in the absence and presence of cysteine, suggesting that active metabolism may be not required for both MeHg and Hg(II) uptake. Our results provide an improved understanding of divalent mercury uptake by non-methylating/non-demethylating bacteria and highlight the possible broader involvement of these bacteria in mercury cycling in natural environments.
研究领域:
微生物学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Water Process Engineering
·
2023
·
IF 7
Mimi Sun,Mengzhu Cao,Jingjuan Wang,Yanni Bi,Chong-Bo Ma
Mercury pollutants, particularly ionic mercury (Hg 2+ ), have been identified by the World Health Organization as among the top ten chemicals posing a significant threat to public health. Adsorption of Hg 2+ onto solid phases has emerged as an effective method for water remediation . However, most existing adsorbents suffer from drawbacks such as complex preparation procedures, secondary pollution, and time-consuming regeneration processes. To address these limitations, we have developed an aerogel adsorbent based on poly(vinyl alcohol) and the auxiliary crosslinker phytic acid. This aerogel can be easily synthesized via a self-assembly process under hydrothermal conditions, offering advantages including excellent mechanical strength, adjustable pore size, and surface area. The aerogel exhibits remarkable adsorption capacity for both Hg 2+ and organic mercury compounds (MeHg + ), and can be regenerated within an incredibly short time (~40 s). Moreover, it demonstrates high removal efficiency of Hg 2+ even in the presence of competing ions such as Mn 2+ , Cd 2+ , Cr 2+ , Cu 2+ , and Pb 2+ . The low-cost raw materials, straightforward synthesis, and facile manipulation during the remediation/regeneration process make this aerogel adsorbent highly promising for practical applications in real-world scenarios.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Analytical Methods
·
2024
·
IF 2.7
Shengji Wu,Guiyuan Hu,Yutao Shen,Rui Tang,Fan Yang,Lei Che,Wei Yang
Determination of mercury species over solid waste from natural gas processing plants is a prerequisite for solid waste decontamination and mercury recycling. The temperature-programmed decomposition and desorption method (TPDD) is a promising technique to determine the mercury species over solid waste. Mercury species over solid wastes with complex components and similar desorption temperature, however, cannot always be determined using only the TPDD method. In the present study, the EPA 3200 method was applied to optimize the TPDD process for speciation of the mercury compound over solid wastes collected from a natural gas processing plant, including four spent adsorbents and three sludges. The mercury species with similar desorption temperatures over solid wastes were completely separated by EPA 3200 method optimized TPDD process. The mercury species over spent adsorbents and sludges could be determined based on the fingerprints of the mercury compounds. The mercury compounds over spent adsorbent were specified to be Hg0 and/or M-Hg amalgam, HgS(Black) and HgO(Red), of which HgS(Black) was the primary mercury compound. However, the mercury species over sludge were analyzed to be Hg0 and/or M-Hg amalgam, HgCl2(minor), HgS(Black), HgO(Yellow) and HgS(Red). The mercury recovery rates of solid wastes ranged from 73% to 120%. With the above results, it was considered that the EPA 3200 method optimized TPDD process was a promising method to specify and semi-quantify the mercury compounds in solid waste.
研究领域:
环境科学
·
分析化学
·
废物管理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2025
·
IF 11.3
Jin Zhang,Pei Lei,Huan Zhong,Nan Zou,Martin Tsz-Ki Tsui,Carl P.J. Mitchell,Chengjun Li,Weiping Cai,Han Meng,Huan He,Fei Dang
The methylation of mercury-containing nanoparticles (Hg-NPs) into neurotoxic methylmercury (MeHg) poses threats to wildlife and humans. However, how autochthonous dissolved organic matter (DOM) affects the occurrence and MeHg production of Hg-NPs remains poorly understood. In this study, the distribution of Hg-NPs and their interactions with autochthonous DOM in the Nanfei River, an urban river in eastern China, were systematically explored. Field investigations revealed that mass concentrations of Hg-NPs increased along the flow path, rising from 0.10 ± 0.06 to 0.91 ± 0.21 ng·L -1 , and were positively correlated with MeHg levels ( p < 0.001), indicating that Hg-NPs (predominantly < 60 nm in diameter) are bioavailable substrates for Hg methylation in the river. The spatial distribution of Hg-NPs was primarily driven by the increasing level and changing composition of DOM along the river, particularly by fractions with a higher degree of humification and higher molecular weight. Laboratory experiments showed that algae-derived DOM, which has a higher content of aromatic protein, was more effective in promoting Hg-NP formation and maintaining their net MeHg production than other DOM sources. These findings highlight the critical role of autochthonous DOM, particularly algae-derived DOM, in regulating the occurrence and methylation of Hg-NPs, providing new insights into MeHg risk prediction under algal blooms.
研究领域:
环境科学
·
生态学
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2024
·
IF 10.8
Zhiying Zhang,Zhanhua Zhang,Chenyang Zhang,Qing Chang,Qingxuan Fang,Chengmei Liao,Jiubin Chen,Pedro J. J. Alvarez,Wei Chen,Tong Zhang
Mercury nanoparticles are abundant in natural environments. Yet, understanding their contribution to global biogeochemical cycling of mercury remains elusive. Here, we show that microbial transformation of nanoparticulate divalent mercury can be an important source of elemental and methylmercury.Geobacter sulfurreducensPCA, a model bacterium predominant in anoxic environments (e.g., paddy soils), simultaneously reduces and methylates nanoparticulate Hg(II). Moreover, the relative prevalence of these two competing processes and the dominant transformation pathways differ markedly between nanoparticulate Hg(II) and its dissolved and bulk-sized counterparts. Notably, even when intracellular reduction of Hg(II) nanoparticles is constrained by cross-membrane transport (a rate-limiting step that also regulates methylation), the overall Hg(0) formation remains substantial due to extracellular electron transfer. With multiple lines of evidence based on microscopic and electrochemical analyses, gene knockout experiments, and theoretical calculations, we show that nanoparticulate Hg(II) is preferentially associated with c-type cytochromes on cell membranes and has a higher propensity for accepting electrons from the heme groups than adsorbed ionic Hg(II), which explains the surprisingly larger extent of reduction of nanoparticles than dissolved Hg(II) at relatively high mercury loadings. These findings have important implications for the assessment of global mercury budgets as well as the bioavailability of nanominerals and mineral nanoparticles.
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）