FUEL
·
2021
·
IF 6.609
Yong Wei,Guijian Liu,Biao Fu,Yuan Liu,Xuan Xue
Fine particulate matter (PM) emitted from coal-fired power plants (CFPPs) has aroused widespread environmental and human health concerns. Cadmium (Cd), as one of the prime toxic air pollutants, which exists in fine PM intensifies its toxicity. In this research, three particle sizes of PM (PM 1 , PM 2.5 , and PM 10 ) at the outlet of electrostatic precipitator (ESP), along with feed coal, bottom ash, and ESP ash, were collected from a 300-MW pulverized CFPP. Results showed that Cd was more enriched in the fly ash than in bottom ash. With the PM diameter decreasing, the relative enrichment index (REI) value of Cd increases from 2.30 to 7.84. The concentration of Cd was found to be intimately related to Ti in the PM. Abundant Ti-rich particles were identified in the PM 1 , having quite different chemical compositions as compared to particles larger than 2.5 μm. The major processes governing the formation of Ti-rich particles included melting of silicate-bound Ti and heterogeneous condensation of gaseous Ti from the decomposition of organic-associated Ti in coal. The transformation behavior of Cd to PM in a coal combustion process was discussed based on its occurrence mode in coal, thermodynamic property, and the possible interactions with ash particle compositions. The retention of Cd (g) by Ti-rich particle were probably dominated by chemisorption at high temperature; at lower temperature, physical adsorption or condensation may be the primary mechanisms for capturing CdCl 2 (g).
研究领域:
环境科学
·
化学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2024
·
IF 10.8
Xiwen Song,Di Wu,Xiu Chen,Zizhen Ma,Qing Li,Jianmin Chen
Acidity is an important property of particulate matter (PM) in the atmosphere, but its association with PM toxicity remains unclear. Here, this study quantitively reports the effect of the acidity level on PM toxicity via pH-control experiments and cellular analysis. Oxidative stress and cytotoxicity potencies of acidified PM samples at pH of 1–2 were up to 2.8–5.2 and 2.1–13.2 times higher than those at pH of 8–11, respectively. The toxic potencies of PM samples from real-world smoke plumes at the pH of 2.3 were 9.1–18.2 times greater than those at the pH of 5.6, demonstrating a trend similar to that of acidified PM samples. Furthermore, the impact of acidity on PM toxicity was manifested by promoting metal dissolution. The dramatic increase by 2–3 orders of magnitude in water-soluble metal content dominated the variation in PM toxicity. The significant correlation between sulfate, the pH value, water-soluble Fe, IC20, and EC1.5 (p < 0.05) suggested that acidic sulfate could enhance toxic potencies by dissolving insoluble metals. The findings uncover the superficial association between sulfate and adverse health outcomes in epidemiological research and highlight the control of wet smoke plume emissions to mitigate the toxicity effects of acidity.
研究领域:
环境科学
·
毒理学
·
公共卫生
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2017
·
IF 5.099
Changkun Xie,Liyan Kan,Jiankang Guo,Sijia Jin,Zhigang Li,Dan Chen,Xin Li,Shengquan Che
Particulate matter (PM) is one of the most serious environmental problems, exacerbating respiratory and vascular illnesses. Plants have the ability to reduce non-point source PM pollution through retention on leaves and branches. Studies of the dynamic processes of PM retention by plants and the mechanisms influencing this process will help to improve the efficiency of urban greening for PM reduction. We examined dynamic processes of PM retention and the major factors influencing PM retention by six trees with different branch structure characteristics in wind tunnel experiments at three different wind speeds . The results showed that the changes of PM numbers retained by plant leaves over time were complex dynamic processes for which maximum values could exceed minimum values by over 10 times. The average value of PM measured in multiple periods and situations can be considered a reliable indicator of the ability of the plant to retain PM. The dynamic processes were similar for PM 10 and PM 2.5 . They could be clustered into three groups simulated by continually-rising, inverse U-shaped, and U-shaped polynomial functions, respectively. The processes were the synthetic effect of characteristics such as species, wind speed, period of exposure and their interactions. Continually-rising functions always explained PM retention in species with extremely complex branch structure. Inverse U-shaped processes explained PM retention in species with relatively simple branch structure and gentle wind. The U-shaped processes mainly explained PM retention at high wind speeds and in species with a relatively simple crown. These results indicate that using plants with complex crowns in urban greening and decreasing wind speed in plant communities increases the chance of continually-rising or inverse U-shaped relationships, which have a positive effect in reducing PM pollution.
研究领域:
环境科学
·
植物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2020
·
IF 7.864
Chi Yang,Chunyan Zhang,Xiaosan Luo,Xiaoyan Liu,Fang Cao,Yan-lin Zhang
So far, studies on the conversion of stereochemistry under photo-Fenton conditions and their atmospheric implication are still rare. Here, we found that the biomass burning marker, the chiral compound levoglucosan (L), undergoes oxidative degradation under photo-Fenton conditions and can be isomerized into mannosan (M) and galactosan (G) simultaneously. Among the formic acid, acetic acid, and oxalic acid in the degradation products of levoglucosan, it was found that the yield of formation of formic acid in the photo-Fenton pathway can be as high as 86%. It is worth noting that both levoglucosan and its isomers are present in the atmosphere and their concentrations are strongly correlated. At the same time, the range of their concentration ratios, L/(G + M), measured in the photo-Fenton experiments in the laboratory was found to agree well with that measured in atmospheric PM2.5 samples. However, the sources of L, G, and M in the atmosphere are complex, and the photo-Fenton reaction may be an essential pathway for the distribution of L, G, and M in the atmosphere.
研究领域:
环境科学
·
大气化学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Danni Wu,Haonan Wu,Yan Lyu,Huiying Zhang,Jiade Wang,Xiang Li,Xiaobing Pang
Atmospheric particulate matter (PM) poses adverse effects on human via producing reactive oxygen species (ROS). Oxidative potential (OP, ability to generate ROS) can be induced by various chemicals in PM, while their interplay remains poorly characterized. Here, we systematically assessed influences of Cu 2+ on OP of Brown carbon (BrC) (e.g., imidazoles) using dithiothreitol (DTT) assay. Results showed DTT consumption rate exhibited an initial rise and later decline (0.25 −0.56 µM/min) along with increase of BrC concentration (0.1 − 2 µM), while no general trend was observed for • OH formation. Although Cu 2+ showed either antagonism or synergism with BrC against DTT consumption, Cu 2+ displayed antagonism with most BrC against • OH generation. Fluorescence quenching experiments provided evidence of complexation between Cu 2+ and water-soluble organic compounds (WSOCs, from ambient PM 2.5 ), which was influenced by Cu 2+ concentration. Further parallel factor analysis of spectra showed that polycarboxylate-type humic acid-like substances (complexation site number ( n ): 0.46, complexation equilibrium constant ( k ): 0.51) and fulvic acid-like compounds ( n : 0.42, k : 0.62) were the main components in WSOCs that complexed with Cu 2+ . Our results suggest the interactions of BrC and copper play a crucial role in PM OP and highlight complexation in evaluation of PM OP.
研究领域:
环境科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Zhenkai He,Xinyu Wang,Yunhe Luo,Yazheng Zhu,Xin Lai,Jingge Shang,Jianqiu Chen,Qianjiahua Liao
Coagulation is a common method used to remove suspended particulate matter (SPM) from the water supply. SPM has preferable adsorption ability for antibiotics in water; therefore, SPM adsorption and coagulation may be a possible way to remove tetracycline (TC) from water. This study carried out coagulation experiments combining SPM collected from a natural lake at a location with three common coagulants—polyaluminum sulfate, polyaluminum chloride, and polyferric sulfate—under different pH values, exploring the adsorption of TC by SPM, coagulation of SPM with TC, and the primary influencing factors of this process. The maximum removal rate of TC can reach 97.87% with an SPM concentration of 1000 mg/L. Multi-factor analysis of variance showed the importance of various TC removal factors, which were ranked as follows: SPM concentration ≫ initial TC concentration > type of coagulant > pH values. The higher the SPM concentration, the better the TC removal (p < 0.001). Fourier infrared spectroscopy results demonstrated the strong adsorption effect of SPM on TC after being combined with a coagulant, and scanning electron microscopy also indicated that SPM becomes effective nuclei in the coagulation process, which is a possible reason for better TC removal. However, the effluent turbidities under 1000 mg/L SPM concentrations were high without coagulant aid. With the addition of coagulant aid anion polyacrylamide, the TC removal remained unchanged, effluent turbidity significantly reduced, and the TC desorption became low. These results indicate that applying SPM from natural lakes in the coagulation process could potentially remove TC in water.
研究领域:
环境科学
·
水处理工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Yutang Kang,Jiahao Chen,Shasha Feng,Huixian Zhou,Fangqi Zhou,Ze-Xian Low,Zhaoxiang Zhong,Weihong Xing
Particulate matters (PMs) emissions from energy consumption contribute the vast majority of PM pollution, which are typically associated with high temperatures (>300 °C) and are difficult to remove directly at high temperatures. Electrospinning nanofiber membranes have irreplaceable advantages of high removal efficiency and low pressure drop for PMs filtration, however, the efficient filtration of PMs at high temperature is challenging for polymer-based nanofiber membranes because of the poor heat resistance and inflammability. Herein, we design a thermally-oxidized polyacrylonitrile/polyvinylpyrrolidone/SnO 2 (OPAN/PVP/SnO 2 ) nanofiber membrane by performing the thermally induced cyclization and oxidation reaction of PAN/PVP/SnCl 2 nanofiber membrane at 350 °C in air. During the thermal oxidization process, Sn 2+ acted as a catalyst and activation, preventing the melting and fusion of PAN nanofibers. The addition of PVP greatly increased the mechanical properties of OPAN/SnO 2 nanofiber membrane. The prepared OPAN/PVP/SnO 2 nanofiber membrane possesses superior PMs filtration performance at room temperature, with the PM 0.3 and PM 2.5 filtration efficiency of 99.53% and 99.98%, respectively. The OPAN/PVP/SnO 2 nanofiber membrane exhibits high temperature tolerance up to 350 °C and wide pH tolerance of 1–14, it remains a high PMs removal efficiency of 98.51% at 350 °C and 98.67% at 300 °C. Moreover, the OPAN/PVP/SnO 2 nanofiber membrane shows excellent fire retarding and self-extinguishing property not shown in pristine PAN nanofiber membrane. This work provides a novel approach for clean use of energy via a cost-effective, heat-resistant, and flame-retardant nanofiber membrane.
研究领域:
环境科学
·
材料科学
·
纳米技术
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2017
·
IF 4.601
Yiquan Guo,Junying Zhang,Yongchun Zhao,Shaolong Wang,Cheng Jiang,Chuguang Zheng
Fly ash fine particles emitted from coal-fired power plants are the primary atmospheric pollutant in China. The pressure, temperature, and velocity distribution of the flow field in a chamber was simulated to evaluate chemical agglomeration. The effect on the removal efficiency of composition, concentration, pH, K + content, and zeta potential of the chemical agglomeration solutions as well as surfactant and flue gas temperature were evaluated. The results suggested that suitable solutions could significantly improve the removal efficiency of fine particles. Among these, kappa-carrageenan performed best and achieved a removal efficiency of 47.1%. Synergism was detected as two different chemical agglomeration solutions were mixed together: a mixture of kappa-carrageenan and konjac glucomannan attained a removal efficiency of 59.3%, higher than their individual values. The efficiency improved initially and then decreased as the solution K + concentration increased. Also surfactants affected agglomeration: cationic and non-ionic surfactants enlarged the removal efficiency by 9.0% and 3.7%, respectively, whereas anionic surfactants lessened average removal efficiency by 5.6%. Zeta potential influenced the removal efficiency as well: it peaked as the zeta potential was around 0 mV.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2021
·
IF 9.297
Yong Wei,Guijian Liu,Biao Fu,Ruwei Wang,Yuan Liu,Xuan Xue,Mei Sun
Inhalable fine particulate matter (PM), which is rich in Pb and other pollutants from coal-fired power plants, can cause air pollution and severe health problems. To facilitate the development of efficient techniques for controlling fine particulate Pb emissions, in this study, various types of size-resolved fine PM (<10.0 μm) were collected from the outlets of fabric filter units (FFs) at an industrial circulating fluidized bed (CFB) power plant to assess the distribution and partitioning behavior of Pb. The results showed that the mass particle size distribution (PSD) of the collected fine PM followed unimodal distribution, peaking at 5.8–4.7 μm, which might be caused by the fragmentation of limestone additives and new-formed CaSO 4 . However, the mass PSD of Pb for size-fractionated PM displayed different distribution pattern. Two peaks were observed in the size ranges of 5.8–4.7 μm and 1.1–0.7 μm. The mechanism of Pb enrichment in the supermicron particles was mainly controlled by the surface adsorption reaction, which could be explained by 1/d p dependence and be improved using excess active CaO produced by the injected limestone. For submicron particles, gas-film transfer or heterogenous condensation (mass transfer) might represent the deposition mechanism . Besides Pb enrichment, it was found that the submicron particles (<0.7 μm) mainly consisted of Si-rich and Si–Al phases. The emission of those fine SiO 2 -bearing particles should be limited as they can be inhaled and can damage the respiratory system.
研究领域:
环境科学
·
公共卫生
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Wenna Wu,Lin Ma,Xiaoli Chen,Li Liu,Shuli Dong,Huiling Zou,Jingcheng Hao
Hypothesis With the rapid development of economy and global industrialization, the problem of air pollution has become a worldwide topic. The efficient filtration of airborne particulate matters (PMs) is critical for human health and environmental sustainability. Experiments Herein, self-supporting bio-based polyelectrolyte aerogels were prepared and acted as the advanced filters for efficient removal of PMs. The natural choline cation (Ch + ) or the organic cation, 1-butyl-3-methylimidazolium (Bmim + ), are introduced into alginate (Alg - ) to form the polyelectrolytes of ChAlg or BmimAlg due to the electrostatic interaction . By the directional freeze-drying in liquid N 2 , hierarchically porous aerogels with mechanical robustness, flexibility and thermo-stability were prepared. This specific structure may permit the polluted air to pass adequately through the aerogel channels, which are conducive to intercept various PMs with different diameters. Findings As an example, the removal efficiency of ChAlg aerogels for PM 10 , PM 2.5 and PM 0.3 are respectively up to (99.24 ± 0.03)%, (99.22 ± 0.02)%, and (93.41 ± 0.22)% within 15 h durability test. One outstanding character lies in ensuring high removal efficiency, while achieving a good balance with the low pressure drop (10 Pa), which is driven by synergistic effect of passive trapping and electrostatic capture. Moreover, the polyelectrolyte aerogels exhibit excellent antimicrobial activity and regenerated capacity. These properties endow the aerogels of polyelectrolyte ChAlg or BmimAlg with remarkable potential as new advanced filters for masks and other personal protective equipment.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2024
·
IF 5.7
Qing Tan,Yuan Yang,Linshan Yang,Dandan Wang,Xiaoling Hou,Kerage Dorothy Mokeira,Jialun Wu,Guibin Lv,Shuxia Xu,Chengbin Zheng
Background The evaluation of particle-bound mercury (PBM) exposure is a crucial aspect of assessing the global cycle of mercury (Hg) and its adverse effects on human health and ecosystems. Nevertheless, the precise and reliable measurement of PBM remains a formidable task because of the costly and cumbersome equipment required, as well as the inadequate sensitivities exhibited by current analytical techniques. In this study, we provided a unique and straightforward approach utilising filter fiber-assisted matrix solid-phase dispersion (FF-MSPD) in conjunction with single-drop solution electrode discharge-induced cold vapor generation atomic fluorescence spectrometry (SD-SEGD-CVG-AFS) for the precise quantification of PBM. The PBM contained in a small filter was efficiently extracted with 200 μL of eluent (0.2 % L-cysteine and 4 % HCOOH) by FF-MSPD and subsequently converted to Hg 0 using SD-SEGD-CVG, before being subjected to examination using AFS. Results The resulted limit of detection (LOD, 3 σ ) was 0.17 pg m −3 , obtained with a sample volume of 12 m 3 , which was much higher than that of the techniques published in the literatures. The aforementioned technique was effectively utilised for the detection of mercury in 19 samples of PM 2.5 and PM 10 which were collected over a span of several months. Signiffcance Contrast to conventional methods, the proposed method offers a range of distinct advantages, including simplified operation, absence of memory effects , enhanced sensitivity, substantial reduction in reagent usage, and decreased secondary pollution. These advantages are particularly valuable for advancing research on the fate, transport, and exposure routes of environmental mercury.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Sciences
·
2022
·
IF 6.796
Rui Liu,Huan-Huan Yang,Hao Zhou,Xianliang Yi,Yang Liu
Particulate matter (PM) is the main contributor to air pollution, and filtration has been reported to be promising for PM capturing. Considering the complexity of polluted air (volatile organic compounds (VOCs) and ozone are likely concomitant with PM particles) and in view of the versatility of MnO 2 for the degradation of VOCs and ozone, the feasibility of MnO 2 materials as PM filtering media was investigated in this study, and the effect of crystal structure on PM filtration was clarified. Compared with the layered δ-MnO 2 , the MnO 2 with tunnel structure (including 1 × 2-, 2 × 2- and 3 × 3-MnO 2 ) exhibited greatly enhanced PM removal efficiencies, and particularly, the 3 × 3-MnO 2 possessed not only significant activity for adsorbing PM particles but also high utilization efficiency of the active surface. Physicochemical properties of the adsorbents were studied by XRD, ATR, isothermal N 2 adsorption, SEM and (HR)TEM. The correlation between pore characteristics and particle elimination activity demonstrates that the most developed mesoporous structure of the 3 × 3-MnO 2 sample played an important role in strengthening the PM adsorption capability. Further comparison of the surface properties of the fresh and spent samples reveals that with respective to the occasion of δ-MnO 2 , the structure of 3 × 3-MnO 2 was robust enough to resist collapse after PM capturing and the great accommodation of the inorganic and organic PM substances in the voluminous pores induced strong affinity between PM particles and 3 × 3-MnO 2 . Thereby, a higher particle filtration ability was retained.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）