ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2023
·
IF 6.8
Chengke Fu,Yichao He,Chengyun Yang,Jieyu He,Luna Sun,Yixin Pan,Liping Deng,Rui Huang,Manli Li,Kaikai Chang
Selenium (Se) as an essential nutrient for human beings at trace concentrations, the allowable concentration for the human is only 40 μg/L. Iron sulfide (FeS) nanoparticles have been applied for excessive of selenium (Se) remediation in surface water and groundwater. In this study, FeS nanoparticles were anchored onto biochar (BC) to reduce agglomeration of FeS and prepared into the composite of FeS-BC by pyrolysis to economically and efficiently remove Se(IV) from simulated wastewater based on the excellent performance of FeS and the low cost of BC. Characterizations presented the uniform anchorage of FeS on the BC surface to prevent agglomeration. The results of batch experiments revealed that the removal of Se(IV) by FeS-BC nanomaterials significantly depended on the pH value, with the maximum removal of ∼174.96 mg/g at pH 3.0. A pseudo-second-order kinetic model well reflected the kinetic removal of Se(IV) in pure Se(IV) solution with different concentration, as well as the coexistence of K + , Ca 2+ , Cl - , and SO 4 2- ions. The presence of K + ions significantly inhibited the removal of Se(IV) with the increase of K + ion concentration compared with the effect of the other three ions. SEM-EDS and XPS analyses indicated that the removal process was achieved through adsorption by surface complexation, and reductive precipitation of Se(IV) into Se 0 with the electron donor of Fe(II) and S(-II) ions. The FeS-BC nanomaterial exhibited an excellent application prospect in the remediation of Se(IV).
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Feipan Liang,Zhiyong Nie,Yuzheng Xia,Yutian Yan,Xiaonong Chen,Bo Liu,Lei Lei,Shuxian Shi
The usage of organophosphate esters as pesticides or nerve agents in chemical warfare caused vital environmental and safety issues. Although metal organic frameworks (MOFs) are often applied to remove the organophosphate esters by adsorption and catalytic degradation, a basic environment with N -ethylmorpholine buffer is essential. In this study, four kinds of zirconium-based MOFs (Zr-MOFs), labeled UiO-66, UiO-67, UiO-67-NH 2 , and UiO-67-2NH 2 , were prepared by the solvothermal method to decontaminate aqueous solutions containing organophosphate esters of paraoxon (POX) and sarin (a nerve agent) without adding any additional basic buffer. Effects of MOF/POX mass ratio and temperature on degradation kinetics and efficiency were investigated in detail. A possible mechanism for the POX decontamination by Zr-MOFs was proposed and verified. Results showed that the POX decontamination catalyzed by Zr-MOFs was a pseudo-first-order reaction. The introduction of amino groups in Zr-MOFs could increase the decontamination rate, which follows the order of “UiO-67-2NH 2 > UiO-67-NH 2 > UiO-67 > UiO-66”. The half-lives of POX and sarin with UiO-67-2NH 2 were 18 min and 5 min respectively, and more than 90% POX and 99% sarin could be decontaminated at room temperature. Compared with previous similar studies on POX degradation in N -ethylmorpholine buffer, UiO-67-2NH 2 performs significantly better in terms of catalytic efficiency and environment. This work would broaden the application scope for the decontamination of aqueous solutions containing organophosphate esters under mild conditions, and offer an effective approach for the treatment of chemical warfare agents in modern society.
研究领域:
环境科学
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材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 45
·23853-23860
·
IF 3.708
Pranav K. Tripathi,Mingxian Liu,Lihua Gan
Synthesis of carbon materials with enhanced surface areas, and regular and tuned pore diameters is always a great challenge. In this report, ordered mesoporous carbons (OMCs) were synthesized by the one-step assembly of tri-constituents, and the OMCs were applied as an adsorbent for the removal of the highly hazardous water pollutant di(2-ethylhexyl)phthalate (DEHP). Phloroglucinol–formaldehyde based carbon precursor was in situ prepared during the assembly of the tri-constituents, and the surface area and mesopore diameter of the OMCs were tuned by variation of the molar ratio of formaldehyde to phloroglucinol. Small angle X-ray diffraction patterns revealed that the obtained carbons are highly ordered, which is in agreement with the measuring results of transmission electron microscopy at low and high resolution. Scanning electron microscopy images demonstrate that OMC-F2.0 has a hierarchical morphology. Nitrogen adsorption–desorption measurements revealed that the surface area of the OMCs (956–1801 m2 g−1) was dependent on the molar ratio of the carbon precursor constituents (formaldehyde to phloroglucinol). By varying the molar ratio of formaldehyde to phloroglucinol from 1.0 to 4.0, the mesopore diameter of the OMCs was shifted to the higher side, from 2.1 to 3.1 nm. DEHP was efficiently removed from a model water pollutant by the OMCs. OMC-F2.0 achieved the highest adsorption capacity of 364 mg g−1 for the removal of DEHP. The adsorption equilibrium data were treated with the two mathematical models of Langmuir and Freundlich, and the results revealed that decontamination was more favorable with the Langmuir model. This concludes that the removal of DEHP by OMCs depends on the surface area, and the DEHP molecules occupied the porous space of the OMCs in a monolayer manner.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
Lei Yue,Linjie Zhao,Jingwei Hou,Junyan Wang,Jiamao Li,Chengjian Xiao
Large amounts of tritiated water (HTO) will be produced during the operation of nuclear power plants and fusion devices, which is harmful to the environment and human due to its radioactivity and toxicity. So, the tritium concentration of tritiated water must be reduced to a very low value before discharge. Hydrogen-water isotope exchange reaction (H 2 + HTO→H 2 O + HT) based on palladium membrane reactor has been proposed to process tritiated water. However, a comprehensive study about the influence of operation parameters on the membrane reactor performance is insufficient, which is not conducive to the design of reactor in practical application. Moreover, the commonly used Pt/Al 2 O 3 or Ni/SiO 2 catalysts are not active for tritiated water dissociation, so the catalytic activity of these catalysts is not high. In order to process tritiated water more effectively, a two-stage membrane reactor has been designed and established in this work, and Pt/TiO 2 catalyst with rich oxygen vacancies is used to catalyze the hydrogen-water isotope exchange reaction for the first time. The membrane reactor performance shows an approximate linear relationship with a new combined parameter S 0.5 P 1.5 R / F 2 ( S is membrane area , F is water flow rate , P is vapor partial pressure, R is swamping ratio), which can be used predict the membrane performance . The isotope exchange reaction activity of Pt/TiO 2 is better than that of Pt/Al 2 O 3 due to its good ability for water dissociation and the hydrogen spillover effect. At last, a tritiated water processing experiment by using two-stage membrane reactor with Pt/TiO 2 catalyst with rich oxygen vacancies has been carried out. The tritium decontamination factor reaches 40588, which is the highest experimental value so far. The results indicate that the two-stage Pd membrane reactor based on hydrogen-water isotope exchange reaction is an efficient technology for tritiated water processing.
研究领域:
环境科学
·
核能工程
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2025
·
IF 21.1
Yang Liu,Xiaowen Zhang,Fashuai Yang,Cuili Xing,Peng Fan,Yuankui Sun,Xiaohong Guan
Zero-valent aluminum (ZVAl) shows promise for environmental remediation, yet its decontamination performance under circumneutral conditions remains debated. To unravel this paradox, we employed Se(IV) and nitrate (NO 3 − ) as model pollutants to probe how contaminant-specific modulation of Al 2 O 3 transformation dictates ZVAl performance across pH 0 2.0–11.0. Results revealed that Se(IV) sequestration exhibited U-shaped kinetics with minimum efficiency at pH 0 4.0–7.0 (5.8–14.2 %), whereas NO 3 − reduction displayed an inverted U-shaped trend with maximum efficiency (> 95 %) obtained in the same pH range. Mechanistic studies demonstrated that these contrasting trends originate from pollutant-mediated Al 2 O 3 evolution. Specifically, Lewis-basicity-dependent competition for Al 2 O 3 surface sites dictates whether hydration or dissolution dominates activation. Se(IV), acting as a strong Lewis base, inhibited Al 2 O 3 hydration by competing with OH − for Al 2 O 3 surface sites and/or forming passivating Al-O-SeO 3 2− complexes , thereby self-limiting its own removal. Conversely, NO 3 − with weak Lewis basicity negligibly affected Al 2 O 3 hydration to form porous Al(OH) 3 , which can enhance electron transfer by reducing interfacial charge transfer resistance. This work resolves the long-standing pH limitation paradox in ZVAl systems by elucidating the role of Al 2 O 3 evolution, thereby offering a mechanistic framework for the design of adaptive metal-based remediation technologies.
研究领域:
环境修复
·
材料化学
·
表面化学
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污染物去除
·
机理研究
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）