APPLIED SURFACE SCIENCE
·
2016
·
IF 3.15
Xiangyu Wang,Peng Liu,Jun Ma,Huiling Liu
For the first time, hydrophilized and functionalized polyacrylonitrile (PAN) membrane was synthesized via two-stage process, addition of polyvinyl alcohol and in situ polymerization of acrylic acid (AA), and nano zero-valent iron (NZVI) was incorporated within modified membrane. The as-prepared PAA/PAN-NZVI (PPN) composites possessed superior reactivity for metronidazole (MNZ) with transformation ratio 2.03 and reaction rate 4.77 times higher than that by bare NZVI. Meanwhile, the enhanced stability and recyclability of PPN composites were maintained over repeated cycles. The major advantages of synthetic method lie in the remarkably increased loading and decreased agglomeration of NZVI. Moreover, with hydrophilized and functionalized synthesis processes of membrane, the potential risk of released iron ions was not a concern due to strong chelation of grafted carboxyl groups. Analyses of morphological characteristics (FE-SEM), chemical structure (FTIR), element valence and groups (XPS) of samples confirmed the successful graft of carboxylic acid groups and formation of a uniform iron nanoparticles coating onto PAN matrix. The reaction kinetics of MNZ with PPN composites were well-described by a two-parameter pseudo-first-order decay model with activation energy of 29.5 kJ/mol. The co-solutes except humic acid had a negligible effect on MNZ transformation. Determination of intermediates revealed that nitro reduction, N-denitration and hydroxyethyl cleavage were the main pathways for transformation of MNZ. The findings suggest that the novel composites possess huge potential for antibiotics wastewater treatment.
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
ULTRASONICS SONOCHEMISTRY
·
2018
·
IF 6.012
Yu-qiong Gao,Nai-yun Gao,Wei Wang,Shi-fei Kang,Jian-hong Xu,Hui-ming Xiang,Da-qiang Yin
This study investigated the degradation of propranolol (PRO), a beta (β)-blockers, by nano zero-valent iron (nZVI) activated persulfate (PS) under ultrasonic irradiation. Effects of several critical factors were evaluated, inclusive of PS concentration, nZVI dosage, ultrasound power, initial pH, common anions, and chelating agent on PRO degradation kinetics. Higher PS concentration, nZVI dosage and ultrasound power as well as acidic pH favored the PRO degradation. Conversely, anions and chelating agent took on the inhibitory effect towards PRO degradation to different extents. Furthermore, the variations of morphology and surface composition of nZVI before and after the reaction were characterized by TEM, XRD and XPS. Finally, on the basis of identified degradation intermediates by LC/MS/MS analysis, this work tentatively proposed the degradation pathways. These encouraging results suggest that US/nZVI/PS process is a promising strategy for the treatment of PRO-induced water pollutant.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Cleaner Production
·
2019
·
IF 6.395
Huimin Zhang,Yang Ruan,Aiping Liang,Kaimin Shih,Zenghui Diao,Minhua Su,Li'an Hou,Diyun Chen,Hui Lu,Lingjun Kong
Currently, a lot of uranium containing wastewater was generated in China, which required efficient treatment before being discharged. Immobilization of uranium on ZVI has attracted many concerns from researchers in the world wide. Surface oxidation and agglomeration limited the efficiency of nano zero-valent iron (nZVI) in remediation of uranium pollution. In this work, a green carbothermal reduction process was conducted to prepare environmental friendly biochar-supported ZVI (nZVI/BC). Immobilization behavior of uranium on nZVI/Cs, oxidized nZVI/Cs and Fe 3 O 4 from wastewater were investigated. The iron salt was converted into iron oxides at 700 °C, further being reduced into nZVI in the presence of ferric chloride and ferric nitrate being carbonization of starch at 800 and 900 °C. The uranium adsorption capacities were different from the carbonization temperature and iron sources, which depended on the transformation of iron species. The maximum adsorption capacities of nano-flake Fe Cl /C (1:4–900) and nanoparticles Fe N /C (1:4–900) for U(VI) were 34.82 and 55.14 mg/g. The removal efficiencies of Fe Cl /C (1:4–900) and nanoparticles Fe N /C (1:4–900) were higher than that of 44% for C–Fe 3 O 4 . The SEM-mapping and XPS analysis of nZVI/Cs after U(VI) adsorption indicated that the immobilization of U(VI) was ascribed to simultaneous adsorption and reduction.
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
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Wei Wang,Yilong Hua,Shaolin Li,Weile Yan,Wei-xian Zhang
A common concern in the approval of nanotechnology for water treatment is whether there are advantages of these nanomaterials over conventional water treatment reagents. In this work, nanoscale zero-valent iron (nZVI) is compared with lime (Ca(OH) 2 ), the most widely used heavy metal precipitant, for Pb(II) and Zn(II) removal, in laboratory and field experiments. Water chemistry, treatment efficiencies and reaction products of the two reagents are compared and the study shows that the moderate solution pH of nZVI and its seed effect play vital roles in producing high-quality effluents. The results are then verified in a field continuous-flow experiment using tons of lime and kilos of nZVI. The results show that sub-ppm levels (∼0.1 mg/L) of Pb(II) and Zn(II) could not be achieved via lime precipitation alone, due to the solubility limits of metal hydroxides and their re-dissolution caused by the strong alkalinity of lime. In comparison, stable and lower levels of Pb(II) and Zn(II) were easily attained using nZVI, due to its multifunctional properties and good tolerance for influent fluctuation enabled by its inherent pH-stabilizing nature. SEM characterizations, particle size analyses and quiescent settling experiments show the ability of nZVI to generate large and consolidated solids that are amenable to gravitational separation. The study shows several key advantages of nZVI over lime technology in Pb(II) and Zn(II) removal. As lime is widely used for heavy metal removal, this work provides an effective advanced treatment process to supplement lime-based treatment methods.
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
CHEMOSPHERE
·
2022
·
IF 8.943
Lianghe Lv,Lina Sun,Chunli Yuan,Yue Han,Zhaohui Huang
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous persistent organic pollutants in soil, which have carcinogenic, teratogenic and mutagenic hazards. The effects of rhamnolipid (RL), nano zero-valent iron (nZVI), and anthraquinone-2,6-disulfonic acid (AQDS) on the degradation of PAHs in soil were studied. It was found that the treatment of 5 mg·kg −1 RL + 1% nZVI +0.2 mmol·kg −1 AQDS had the highest degradation rate. The degradation rate of total PAHs and HMW-PAHs was 72.81% and 79.47% respectively after 90 days. High-throughput sequencing showed that in RL + nZVI + AQDS enhanced soil, Clostridium , Geobacter , Anaeromyxobacter and Sphingomonas were the dominant species for anaerobic degradation of PAHs. Rhodococcus , Nocardioides , and Microvirga are the dominant species for aerobic degradation of PAHs. The activities of methyltransferase, dehydrogenase and catechol 1,2-dioxygenase in the anaerobic-aerobic degradation process of PAHs were consistent with the degradation process of PAHs, indicating the role of these enzymes in the degradation of PAHs. RL, nZVI, and AQDS combined enhanced microbial anaerobic-aerobic degradation has great application potential in remediation of PAHs-contaminated soil.
研究领域:
环境科学
·
土壤学
·
生物修复
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Yongkui Li,Suqin Li,Binbin Hu,Xin Zhao,Penghui Guo
Metallurgical wastewater with high arsenic (As) concentration presents important challenges to human health and the environment because of its high toxicity and carcinogenicity. Iron (Fe)-based adsorbents can effectively detoxify low As-containing wastewater but are less helpful for high concentration of As and for solid–liquid separation. Herein, an advanced strategy is proposed to dispose high As wastewater using nano-zerovalent iron (nZVI) and ferric oxyhydroxide (FeOOH) combined with superconducting high gradient magnetic separation (HGMS) technology. The superconducting HGMS technology promoted the removal of As by nZVI and FeOOH via a magnetic flocculation reaction, while simultaneously separating reaction products adsorbed As from wastewater. Interestingly, nZVI could be corroded to release Fe(II) ions which then generated Fenton reaction under aerobic conditions, facilitating the oxidization of As(III)/Fe(II) to As(V)/Fe(III) ions. The Fe(II) and Fe(III) hydrolyzed in the form of hydroxy hydroxide and further generated the magnetic flocculates and coprecipitate. The results showed that 99.06% of As was successfully removed from wastewater with an initial As concentration of 5358 mg/L, at a dosage of 20 g/L, a magnetic field strength of 5 T, and a flow velocity of 500 mL/min. Compared with FeOOH, nZVI showed more favorable adaptability for lead smelting wastewater. Removal of As from wastewater by using nZVI combined with superconducting HGMS technology has a great potential to achieve industrial application for metallurgical heavy metal wastewater.
研究领域:
环境科学
·
材料科学
·
水处理技术
✓ 已验证
产品关联
DOI
高影响因子
Environmental Science-Water Research & Technology
·
2022
·Vol. 8
·期 11
·2567-2579
·
IF 5.819
Fang Cheng,Jun Hou,Jun Wu,Yi Xu,Lingzhan Miao,Jun Xia,Zongli Huo
pentachlorophenol (PCP) is a kind of chlorinated aromatic contaminant that brings challenges from an environmental perspective. However, the performance of sulfidated nanoscale zero-valent iron (S-nZVI) in PCP removal remains unknown. In this study, S-nZVI was applied in the treatment of PCP-polluted water under different water chemistry conditions. The results showed that PCP was removed under the combined action of adsorption, dechlorination, and ˙OH-mediated oxidation, among which dechlorination played a leading role while oxidation lagged behind. The amount of adsorbed PCP correlated well with the PCP dechlorination rate constant (kred), except for S/Fe 0 and 0.1 and acidic initial pH (pHinitial) conditions. At neutral and alkaline pHinitial, kred increased with an increase in pHinitial due to the formation of a hydroxide layer that facilitates adsorption. At acidic pHinitial, kred increased with a decrease in pHinitial because hydrogen ions diffusing in the solution participated in the reaction. The effects of solution chemistry, such as anions, organic matter, and oxygen conditions, on PCP adsorption and transformation were also studied. Eight degradation byproducts were observed; the dechlorination products suggested that PCP dechlorination by S-nZVI occurred via a sequential pathway. PCP and its dechlorination products would then undergo ˙OH-mediated oxidation, resulting in products that are beneficial for microbes. Changes to S-nZVI after reacting and the role of sulfur were also discussed. This study confirmed that S-nZVI can be effective in the remediation of PCP-polluted groundwater. Further research is needed to optimize this remediation via coupling microbial technology and controlling the oxygen conditions.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2021
·
IF 19.503
Peng Huang,Peng Zhang,Cuiping Wang,Jingchun Tang,Hongwen Sun
Persulfate-based (PS-based) advanced oxidation process is a promising technology for degradation of organic pollutants . PS activation needs efficient and economical catalysts and heterogeneous Fe-carbon composites are competitive. Herein, novel N-doped biochar-loaded nanoscale zero-valent iron (nZVI) composites (Fe@N-BC) were synthesized and evaluated for PS activation. Detailed characterization data indicated that graphitic and pyridine N structures were introduced by N-doping, which enhanced the anchoring, dispersion and loading of amorphous nZVI on biochar. Remarkably, the optimized Fe@N-BC material, Fe@N 2 -BC 900 , presented excellent catalytic performance for PS activation for lindane removal. The N-doped defects in biochar acted as reactive bridges and accelerated the electron transfer between nZVI and PS, showing strong synergistic effects toward nZVI. O 2 • − and 1 O 2 were the dominant active species in catalytic systems. Additionally, Fe@N 2 -BC 900 catalyst showed effectiveness over a wide pH range for lindane removal. This work provides a new approach to the rational design and application of Fe@N-BC for persulfate activation in pollution control, which is certified by deep exploration of reaction mechanism.
研究领域:
环境科学
·
化学工程
·
材料科学
·
污染控制
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 58
·36826-36835
·
IF 3.361
Yunlong Shi,Changjiang Yu,Mengying Liu,Qiang Lin,Man Lei,Darun Wang,Mengwei Yang,Yuting Yang,Jian Ma,Zhengya Jia
In this study, a spherical Fe/C composite (AIBC) was successfully prepared via carbonization of Fe3+-crosslinked sodium alginate. The removal capacity and mechanism of AIBC were evaluated for the adsorption of Pb(II) from aqueous solution and compared with that of commercial nanoscale zero-valent iron (nZVI). The effects of the initial concentration, pH of Pb(II) solution, the contact time, coexisting anions, and aging under air were investigated. The results showed that the pH had a strong impact on the adsorption of Pb(II) by AIBC. The adsorption data for AIBC followed the Langmuir model, while the maximum adsorption capacity at pH 5 was 1881.73 mg g−1. The AIBC had a higher adsorption capability than nZVI, especially under the condition of relatively high Pb(II) concentrations. The oxidation–reduction reaction between Fe and Pb(II) was the main mechanism for the adsorption of Pb(II) onto nZVI. AIBC converted the largest amount of Pb(II) into PbO·XH2O/Pb(OH)2 mainly by generating Fe2+.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Water Cycle
·
2025
·
IF 8.7
Xiaobin Zhou,Chenyu Zhou,Min Huang,Yingxue Wang,Mengxin Zhao,Yanan Zhang,Yinming Fan,Yinian Zhu,Zongqiang Zhu
Nano zero-valent iron (nZVI) has garnered significant attention as an excellent environmental remediation material for Cr(Ⅵ) adsorption. However, its practical utilization is significantly impeded by inherent limitations, notably its propensity for aggregation and susceptibility to oxidation. This study proposed an innovative approach that using zeolite imidazole framework-8 (ZIF-8) as a cladding material for encapsulating nZVI particles. This encapsulation served to safeguard nZVI from oxidation and agglomeration. Furthermore, the ZIF-8 coating possessed suitable pore channels, allowing the migration of Cr(VI) ions towards the nZVI’s surface, thereby enabling efficient reduction. The ZIF-8-coated nZVI composite (ZIF-8@nZVI) achieved a remarkable Cr(VI) removal efficiency of 98.43% under the optimized conditions. After 10 days of exposure in the aqueous solution, the efficiency remained above 84%. The uptake of Cr(VI) by ZIF-8@nZVI proceeded via a chemisorption pathway, inherently spontaneous and endothermic in character. The mechanism analysis indicated that ZIF-8 and nZVI exhibited synergistic enhancement effect on Cr(VI) removal. The protonated nitrogen groups within ZIF-8 facilitated the swift diffusion of negatively charged Cr(VI) ions to the surface of ZIF-8@nZVI. Once adsorbed, Cr(VI) was directly reduced to Cr(III) by Fe 0 , which in turn underwent oxidation to Fe(II)/Fe(III). Notably, Fe(II) indirectly reduced Cr(VI) to Cr(III), while itself being oxidized to Fe(III). Consequently, the resulting Cr(III) ions co-precipitated with Fe(III), forming hydroxide complexes that were eliminated from the aqueous environment. Overall, this research demonstrated the practicability of employing ZIF-8 as a coating material to develop highly efficient nZVI-based adsorbents and highlighted the potential of ZIF-8@nZVI in addressing Cr(VI) contamination challenges.
研究领域:
环境修复
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Kai Liu,Fangbai Li,Xiaolei Zhao,Guoying Wang,Liping Fang
Carbonaceous supports (e.g. biochar) have been widely applied to enhance the performance of nanoscale zero-valent iron (nZVI) for removing heavy metals (e.g. arsenic; As) due to their large surface areas (SSA) to alleviate nZVI particles aggregation, while their electrochemical properties are largely overlooked. Herein, the role of these two characteristics in enhancing As(III) removal has been systematically investigated through designing two parallel experiments to identify the effects of the two characteristics of biochar. Our results suggest that biochar with varying surface areas (33.38–470.36 m 2 /g) supported nZVI exhibits a substantially higher the As(III) oxidation rate (29.7–34.3%) and removal [295.5–371.5 mg/(g·nZVI)] efficiency compared to that by nZVI [27.1%; 192.7 mg/(g·nZVI)]. Despite the importance of SSA, the biochar with extremely low SSA of 33.38 m 2 /g appears to have comparable capacity of enhancing nZVI’s performance with a nZVI loading up to 50%. On the contrary, electrochemical analysis suggests that the oxidation and removal of As(III) are highly related to the electron accepting capacity of biochar, indicating a strong electrochemical effect of biochar in As(III) removal varying with pyrolysis temperature. Surface quinone moieties are found responsible for enhancing electron transfer between biochar [up to 0.25 mmol e·(g biochar) −1 ] and nZVI, promoting nZVI corrosion and the generation of reactive oxygen species (ROS; mainly · O 2 - ) for enhancing the As(III) oxidation and removal. These findings highlight the important role of electrochemical properties of carbonaceous supports rather than SSA in developing nZVI-based materials for further improving heavy metals removal.
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
SCIENCE OF THE TOTAL ENVIRONMENT
·
2018
·
IF 4.61
Usman Farooq,Muhammad Danish,Shuguang Lyu,Mark L. Brusseau,Mengbin Gu,Waqas Qamar Zaman,Zhaofu Qiu,Qian Sui
The surface properties of nanocomposites are influenced by the existence of inorganic species that may affect its performance for specific catalytic applications. The impact of different ionic species on particular catalytic activity had not been investigated to date. In this study, the surface charge (zeta potential) of graphene-oxide-supported nano zero valent iron (G-nZVI) was tested in definitive cationic (Na + , K + , Ca 2+ and Mg 2+ ) and anionic (Br − , Cl − , NO 3 − , SO 4 2− , and HCO 3 − ) environments. The efficiency of G-nZVI catalyst was inspected by measuring the generation of reactive oxygen species (ROS) for the degradation of 1,1,1-trichloroethane (TCA) in sodium percarbonate (SPC) system. Tests conducted using probe compounds confirmed the generation of OH and O 2 − radicals in the system. In addition, the experiments performed using scavenging agents certified that O 2 − were primary radicals responsible for TCA removal, along with prominent contribution from OH radicals. The study confirmed that G-nZVI catalytic capability for TCA degradation is notably affected by various cationic species. The presence of Ni 2+ and Cu 2+ significantly enhanced (94%), whereas Na + and K + had minor effects on TCA removal. Overall, the results indicated that groundwater ionic composition may have low impact on the effectiveness of G-nZVI-catalyzed peroxide TCA treatment.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）