CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Rihong Xiao,Yili Zhang,Shuzhou Wei,Xing Chuai,Xiangzheng Cui,Zhuo Xiong,Junying Zhang,Yongchun Zhao
Massive Hg emissions from coal-fired units cause serious environmental pollution and result in a substantial waste of Hg resources. In this study, the prepared millimeter-grade Se/SiO 2 adsorbent was applied as a filler to adsorb mercury in a fixed-bed reactor to obtain the high value-added product HgSe, which solved the problem of short contact time and secondary pollution caused by the traditional injection mercury removal adsorbents. Experimental Hg removal showed that the 25 % Se-loaded adsorbent exhibited excellent Hg removal performance at 150 °C, with a saturation adsorption capacity of mercury was as high as 101.04 mg/g, nearly 300 times that of commercial activated carbons. Additionally, the influence of the flue gas composition on the Hg removal performance of Se/SiO 2 was studied. The results showed that O 2 , NO, and HCl increased the efficiency of Hg removal and SO 2 and SO 3 had trivial impact on the Hg removal performance. The Hg temperature-programmed desorption test results showed that the adsorbed Hg appeared predominantly as HgSe on the sample surface. DFT calculations verified that Se loading improved Hg removal performance and defined the adsorption mechanism. Moreover, the prepared Se/SiO 2 adsorbent carrier was soluble SiO 2 , which provided a good condition for the subsequent high-purity collection of HgSe. Finally, the technological process of Hg removal via Se-loaded adsorbents and the recovery of HgSe were proposed, which could offer a new way to achieve the resource utilization of Hg.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
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2024
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IF 1.6
Muhammad Sarfraz,Yang Li,He Yang,Lijun Jin,Haoquan Hu
Mercury (Hg 0 ) emission from coal-fired industrial plants poses severe threats to ecosystem sustainability and human health, urging the development of novel and cost-effective adsorbents to treat industrial flue gas. Herein, the modification of industrial residual red mud (RM) through the impregnation of hydrogen halides (HH) and its adsorption characteristics for removing elemental mercury from combustion flue gas was reported. Experimental investigation of HH-modified RM reveals that the hydrogen iodide (HI)-modified RM with a concentration of 1.5 M had a maximum Hg 0 removal efficiency of 98%, whereas hydrogen bromide (HBr) 1.5 M modified RM had a maximum Hg 0 removal efficiency of 90%. The effect of various parameters, such as reaction temperature and halide concentrations, were also found to be influential for the adsorption efficiency of the modified RM. Moreover, it is important to highlight the chemisorption characteristics of HI-modified RM, which significantly enhances the efficiency of the removal process. The Hg 0 removal efficiency increases with the increase in HI concentration (1.5 M @ 93%) with an optimal reaction temperature of 140°C. Furthermore, the maximum Hg 0 removal attained with a change in NO concentration was 98% at 200 ppm. However, increasing the SO 2 concentration reduces the efficiency of RM for removing Hg 0 in simulated coal combustion flue gas. The pseudo-second-order model ( R 2 = 0.98) accurately describes the adsorption of in kinetic investigations, indicating a chemisorption mechanism. This analysis of the chemisorption mechanism highlights the efficiency of halide-modified industrial solid waste, which has the potential to be used in the design of economical and innovative adsorbents for reducing environmental pollution. The present study employed specific reaction parameters such as reaction temperature, halide loading contents, and different flue gas compositions, which had not been extensively explored.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
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2024
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IF 0
Zheng Yang,Zhang Lin,Wang Xiaocong,Guo Fenghui,Xing Yi,Li Guoliang,Yue Tao
The substantial amount of mercury emissions from coal-fired flue gas causes severe environmental contamination. With the Minamata Convention now officially in force, it is critical to strengthen mercury pollution control. Existing activated carbon injection technologies suffer from poor desulfurization performance and risk secondary-release risks. Therefore, considering the potential industrial application of adsorbents, we selected cost-effective and readily available activated coke (AC) as the carrier in this study. Four metal selenides—copper, iron, manganese, and tin—were loaded onto the AC to overcome the application problems of existing technologies. After 120 min of adsorption, the CuSe/AC exhibited the highest efficiency in removing Hg 0 , surpassing 80% according to the experimental findings. In addition, the optimal adsorption temperature window was 30–120 °C, the maximum adsorption rate was 2.9 × 10 −2 mg·g −1 ·h −1 , and the effectiveness of CuSe/AC in capturing Hg 0 only dropped by 5.2% in the sulfur-containing atmosphere. The physicochemical characterization results indicated that the AC surface had a uniform loading of CuSe with a nanosheet structure resembling polygon and that the Cu-to-Se atomic ratio was close to 1:1. Finally, two possible Hg 0 reaction pathways on CuSe/AC were proposed. Moreover, it was elucidated that the highly selective binding of Hg 0 with ligand-unsaturated Se − was the key factor in achieving high adsorption efficiency and sulfur resistance in the selenium-functionalized AC adsorbent. This finding offers substantial theoretical support for the industrial application of this adsorbent. Graphical Abstract
研究领域:
环境科学
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材料科学
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DOI
PubMed
ACS Applied Nano Materials
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2018
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IF 0
Zequn Yang,Hailong Li,Chen Liao,Jiexia Zhao,Shihao Feng,Pu Li,Xi Liu,Jianping Yang,Kaimin Shih
Rattle-type Fe3O4@CuS synthesized using a two-step method was applied for elemental mercury (Hg0) adsorption in coal combustion flue gas for the first time. The Fe3O4 with strong magnetization was an ideal candidate as a core to make the sorbent recyclable, while the stabilized ultrathin CuS shell assured that the Fe3O4@CuS had a higher Brunauer–Emmett–Teller (BET) surface area with more exposed active sites and stronger magnetization. The optimal operating temperature of 75 °C allowed for the injection of the sorbent between the wet desulfurization (WFGD) and wet electrostatic precipitator (WESP), which removed the detrimental influence of nitrogen oxides. Simulated flue gas (SFG) in this section showed a slight inhibitive effect on Hg0 adsorption over the Fe3O4@CuS, mainly due to the presence of water vapor (H2O). The inhibition of H2O was proven to be the result of an active site prevention effect instead of the widely recognized competitive adsorption effect. The adsorption capacity and rate of the Fe3O4@CuS for Hg0 capture reached 80.73 mg g–1 and 13.22 μg (g min)−1, which were the highest values among the magnetic sorbents currently reported for Hg0 removal from coal combustion flue gas. These properties allowed the sorbent to maintain a 100% Hg0 capture efficiency for more than 20 h with only a 50 mg dosage when no regeneration step was applied. Meanwhile, the contacting time between the sorbent and Hg0 was generally less than 5 s in a typical sorbent injection process. Polysulfides dominated the capturing process and primarily contributed to the extremely high adsorption capacity/rate. A multistep reaction mechanism was proposed to explain the Hg0 adsorption over Fe3O4@CuS. At the first stage, polysulfide participated in Hg0 adsorption as the most active component and was consumed rapidly. After that, S–S dimers, sulfides, and even copper-terminated sites functioned as the adsorption centers. The as-formed mercury–copper (Hg–Cu) amalgam was transformed into mercury sulfide (HgS), a process that was dependent on the extent of the saturation of sulfide sites. With these advantages, Fe3O4@CuS is a promising, cost-effective, highly recyclable, and efficient alternative to the traditional activated carbon for capturing Hg0 in coal combustion flue gases.
研究领域:
环境科学
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材料科学
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产品关联
DOI
Journal of Environmental Sciences
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2024
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IF 5.9
Lin Zhang,Yang Zheng,Guoliang Li,Jiajia Gao,Yali Tong,Tao Yue
With the rapid development of adsorbents for removal of elemental mercury (Hg 0 ) from coal combustion flue gas, the preparation of adsorbents with superior performance, lower cost and environmental friendliness remains an important challenge. An incipient wetness impregnation method followed by in-situ selenization was used to load copper selenide (CuSe) onto the surface of optimal magnetic biochar (OMBC). The results showed that CuSe significantly enhanced the Hg 0 removal performance of the OMBC, and CuSe loading ratio of 10 % (10CuSe/OMBC) had the best Hg 0 removal performance. 10CuSe/OMBC maintained its Hg 0 removal efficiency above 95 % for 150 min at 30∼150 °C, and it had a good resistance to SO 2 . The equilibrium adsorption capacity of 10CuSe/OMBC could reach up to 8.73 mg/g, which was close to the theoretical value 12.99 mg/g, and the adsorption rate was up to 20.33 µg/(g·min) Meanwhile, 10CuSe/OMBC had strong magnetism that is not permanently magnetized, which could be separated from desulfurization gypsum and recycled many times. Characterization results demonstrated that Se 2 2- , Cu 2+ and O β played essential roles in the oxidation of Hg 0 , and Se 2 2- and Se 2- can immobilize Hg 2+ to HgSe. 10CuSe/OMBC has important guiding significance for practical application because of its low cost, high performance and low mercury leaching characteristic to form HgSe.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Shengyan Liu,Wensheng Lin,Ao Wang,Wei Chen,Liangying Yu,Chong Tian
The mass discharge of mercury from coal-fired power plant has caused great harm, abating mercury emissions is of preoccupation for protecting public environmental safety and human health. Metal oxides are often used for Hg 0 removal in the flue gas. In this paper, a hollow tubular MnO x (MnCot) was successfully prepared by rapid flame annealing using cotton fiber as a sacrificial template. The MnCot were then well characterized and tested for its capability for Hg 0 removal in flue gas. The results indicate that the flame assisted synthesis method for rapidly prototyping metal oxides with typical structures is achievable. The hollow tubular structure of the cotton fiber is well reprinted with good crystallization of Mn 3 O 4 . The inner diameter of the hollow tubular MnCot is about 10 μm, and the thickness of the tube is about 1 μm. The Hg 0 removal efficiency on MnCot can be maintained as high as 90 % under simulated flue gas atmosphere below 240°C. O 2 and NO have a positive effect on the Hg 0 removal, which can act as the fresh active sits thus enhancing its capability for Hg 0 removal. However, the presence of SO 2 will result in the surface sulfation on MnCot, thus deteriorating its capability for Hg 0 removal. Further, the competitive adsorption between SO 2 and Hg 0 on the material will also weaken its capability for Hg 0 removal. The hollow tubular MnO x rapidly prepared by one-step flame annealing has a good industrial application potential for Hg 0 removal in coal-fired flue gas.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2022
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IF 4.326
Shujun Sun,Jun Zhang,Changdong Sheng,Hui Zhong
A novel Na2SiO3/Fenton system was employed for NO removal from coal-fired flue gas in a bubble reactor. The NO removal efficiency of this system could reach 94.36% when the flue gas residence time was 3 s. The hydrolysis reaction of Na2SiO3 produced OH-, which made the solution alkaline, and the formation of iron-based colloids in the alkaline environment effectively catalyzed the generation of free radicals from H2O2, O2•– radicals, which was the main reason for the increase of NO removal efficiency. The reaction of H2O2 catalyzed by iron-based colloids increased the solution pH, which could not only further improve the NO removal efficiency but also enhance the useless decomposition of H2O2. Na2SiO3 could buffer the solution pH, which weakened the ineffective decomposition of H2O2 and prolonged the effective denitrification time. The X-ray diffraction and ion chromatography analysis showed that NO was finally converted to NO3– and NO2–.
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
FUEL
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2020
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IF 5.578
Dongjing Liu,Lingtao Yang,Bin Li,Jiang Wu
Graphitic carbon nitride (g-C 3 N 4 ) has attracted increasing interest owing to its unique electronic property, facile synthesis, chemical and thermal stability. In this work, a graphene-like g-C 3 N 4 is synthesized by direct thermal polymerization of environmentally benign guanidine thiocyanate. The graphene-like g-C 3 N 4 is further modified with NH 4 Br via incipient-wetness impregnation approach and applied to remove Hg 0 from coal-fired flue gas. The results indicate that the optimal polymerization temperature is 700 °C. The Hg 0 removal performance of g-C 3 N 4 is enhanced by NH 4 Br modification. The optimal NH 4 Br content and reaction temperature range are 3 wt% and 120–180 °C, respectively. NO exerts a promotional effect on mercury removal, while SO 2 displays a dual impact on Hg 0 adsorption. Low concentration of SO 2 is beneficial for mercury removal, whereas high concentration of SO 2 restrains Hg 0 removal to some extent. The edge carbons of g-C 3 N 4 may function as the principal reactive sites for Hg 0 removal. The Hg 0 might be captured on the armchair edge carbons of the g-C 3 N 4 by forming covalent carbon-mercury bonds via Lewis acid-base conjugation. Loading NH 4 Br onto g-C 3 N 4 may produce carbenium bromine ion pairs at the zigzag edge carbons that represent as oxidation sites, which convert Hg 0 into HgBr 2 . Besides, the adsorbed Hg 0 may also be oxidized into HgO by the chemisorbed oxygen.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
ENVIRONMENTAL TECHNOLOGY
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2020
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IF 2.213
Shengcai Wang,Zequn Yang,Jiexia Zhao,Hailong Li,Jianping Yang,Jianfei Song,Xueyi Guo
Developing efficient sorbents with rapid kinetics is the main challenge encountered for Hg0 capture from coal combustion flue gas in a sorbent injection scenario. Binary mineral sulfide-based materials combining copper sulfide (CuS) and zinc sulfide (ZnS) to exert their capabilities for Hg0 capture at the low- and high-temperature was for the first time reported for Hg0 removal to realize a wide temperature range sorbents. When the molar ratio between CuS and ZnS was 10%, the as-synthesized 10Cu-Zn nanocomposite exhibited excellent Hg0 uptake rate at 150°C that could degrade 40 μg/m3 of Hg0 to undetectable level at the end of a 60-s experiment with the dosage of only 1 mg. This Hg0 uptake rate is folds higher compared to that when bare CuS or ZnS was adopted alone at this specific temperature. The typical flue gas atmospheres had negligible effect on Hg0 removal over 10Cu-Zn in a short contact time, which further suggests that the binary sorbents were proper to be injected before the electrostatic precipitator system. Moreover, it is found that, by adjusting the ratio between CuS and ZnS, it is potential to develop binary sorbent suiting any temperature conditions that may achieve an exceedingly high Hg0 capture performance. Thus, this work not only justified the candidature of 10Cu-Zn as a promising alternative to traditional activated carbon for Hg0 capture from coal combustion flue gas but also guided the future development of multi-component mineral sulfide-based sorbents for Hg0 pollution remediation from various industrial flue gases.
研究领域:
环境科学
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大气污染控制
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材料科学
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化学工程
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能源工程
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2023
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IF 13.6
Yuzhu Zhang,Yao Pei,Qian S. Liu,Yurou Gao,Ke Min,Zigu Chen,Zhao Shu,Qian Liu,Qunfang Zhou,Guibin Jiang
Atmospheric particulate matter (PM) perturbs hematological homeostasis by targeting the plasma kallikrein-kinin system (KKS), causing a cascade of zymogen activation events. However, the causative components involved in PM-induced hematological effects are largely unknown. Herein, the standard reference materials (SRMs) of atmospheric PM, including emissions from the diesel (2975), urban (1648a), and bituminous coal (2693), were screened for their effects on plasma KKS activation, and the effective constituent contributing to PM-induced KKS activation was further explored by fraction isolation and chemical analysis. The effects of three SRMs on KKS activation followed the order of 2975 > 1648a > 2693, wherein the fractions of 2975 isolated by acetone and water, together with the insoluble particulate residues, exerted significant perturbations in the hematological homeostasis. The soot contents in the SRMs and corresponding isolated fractions matched well with their hematological effects, and the KKS activation could be dependent on the soot surface oxidation degree. This study, for the first time, uncovered the soot content in atmospheric PM with different origins contributed to the distinct effects on plasma KKS activation. The finding would be of utmost importance for the health risk assessment on inhaled airborne fine PM , given its inevitable contact with human circulatory system.
研究领域:
环境科学
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医学
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毒理学
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产品关联
DOI
PubMed
高影响因子
FUEL
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2023
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IF 7.4
Xin Huang,Zijun Ran,Zhi He,Jingyu Ran
Mercury has a significant impact on environment and is mainly derived from coal-fired power plant. Herein, we report a potential route for efficient removal of Hg 0 via oxidation reactions using Ce-doped LaCoO 3 supported on CeO 2 catalyst. Catalyst characterization results proved that Ce can successfully substitute a desired part of Co into the LaCoO 3 crystal lattice via a sol–gel method. The Hg 0 removal experiments suggest that Hg 0 removal efficiency decreased in the order of La 0.875 Ce 0.125 CoO 3 /CeO 2 > La 0.875 Ce 0.125 CoO 3 > LaCoO 3 . The presence of O 2 provided more active oxygen and resulted in approaching 100% Hg 0 removal efficiency. Introducing H 2 O and sole SO 2 would significantly reduce the Hg 0 removal efficiency as a result of competitive adsorption on the actives sites of the catalyst. On the other hand, SO 2 could reacted with Hg 0 in the presence of O 2 and thereby recover the high Hg 0 removal efficiency and the La 0.875 Ce 0.125 CoO 3 /CeO 2 catalyst presented a good performance towards sulfur resistance. Furthermore, the catalyst still exhibited a high Hg 0 removal efficiency performance after five times consecutive recycles.
研究领域:
环境科学
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催化
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材料科学
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能源工程
✓ 已验证
DOI
高影响因子
FUEL
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2025
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IF 7.5
Xiao Zhang,Xueying Zhang,Cai Liang,Feng Shen,Boxiong Shen
Water poisoning remains a significant challenge for Mn-based catalysts in the purification of low-temperature industrial flue gas. In this study, a water-resistant catalyst, Cu-doped MnO x dispersed on a flower-like hollow sphere carrier (Cu 0.1 Mn 1 -Al 2 O 3 (NF)), was developed. The introduction of 5 % water vapor into simulated flue gas reduced the o-xylene oxidation efficiency of the unmodified MnO x /γ-Al 2 O 3 catalyst by 20 %, whereas Cu 0.1 Mn 1 -Al 2 O 3 (NF) exhibited only a 5 % reduction, and it shows a water resistance surpasses those of most of the reported MnO x catalysts. Upon water vapor withdrawal, Cu 0.1 Mn 1 -Al 2 O 3 (NF) showed a 2 % irreversible efficiency loss, compared to 9 % for MnO x /γ-Al 2 O 3 . Mechanistic studies highlight the role of the flower-like morphology in reducing hydrogen-bonded H 2 O and the primary contribution of Cu + doping in suppressing –OH generation on metal sites, likely due to weakened H 2 O dissociation at Mn-Ov-Cu oxygen vacancies. Additionally, Cu 0.1 Mn 1 -Al 2 O 3 (NF) has improved water desorption capability evidenced by 8 °C lower endothermic temperature for H 2 O volatilization than that of MnO x /γ-Al 2 O 3 . Furthermore, a H 2 O-involved Mars-van Krevelen (MvK) mechanism was proposed to explain the ∼ 2 % irreversible efficiency reduction for Cu 0.1 Mn 1 -Al 2 O 3 (NF) in wet gas − attributed to H 2 O dissociation at oxygen vacancies hindered lattice oxygen replenishment. Based on this mechanism, an air-purging regeneration protocol was developed to enhance the catalyst’s operational stability under wet flue gas conditions.
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DOI
高影响因子
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