AUSTRALIAN JOURNAL OF CHEMISTRY
·
2018
·Vol. 71
·期 6
·416-421
·
IF 1.059
Ouyang Dong,Zhihong Zhang,Zhenhai Fu,Xiang Li
A new phase-change material (PCM) CaCl2·6H2O + MgCl2·6H2O + NH4Cl was investigated in this paper. MgCl2·6H2O and NH4Cl were mixed with CaCl2·6H2O to obtain CaCl2·6H2O as a eutectic hydrate salt. The results show that the eutectic composition of the PCM is as follows: 90 wt- % CaCl2·6H2O, 6.25 wt- % MgCl2·6H2O and 3.75 wt- % NH4Cl; the undercooling degree is less than 1.5°C when the nucleating agent is 2 wt- % SrCl2·6H2O or 1.5 wt- % Ba(OH)2·8H2O. The phase-change temperature and latent heat are respectively 25.3°C and 144.3 J g−1 when the composition is 90 wt- % CaCl2·6H2O, 6.25 wt- % MgCl2·6H2O, 3.75 wt- %, NH4Cl, with 2 wt- % SrCl2·6H2O as nucleating agent, and 2 wt- % carboxymethyl cellulose as thickener. In addition, when the composition is changed to 90 wt- % CaCl2·6H2O, 6.25 wt- % MgCl2·6H2O, 3.75 wt- % NH4Cl, 1.5 wt- % Ba(OH)2·8H2O and 2 wt- % carboxymethyl cellulose, the phase change temperature and latent heat are 25.2°C and 139.3 J g−1, respectively.
研究领域:
材料科学
·
热能存储
·
化学工程
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2024
·
IF 10.8
Ying Chen,Lei Tian,Wen Liu,Yi Mei,Qiu-Ju Xing,Yi Mu,Ling-Ling Zheng,Qian Fu,Jian-Ping Zou,Daishe Wu
Dechlorination of chloropyridines can eliminate their detrimental environmental effects. However, traditional dechlorination technology cannot efficiently break the C–Cl bond of chloropyridines, which is restricted by the uncontrollable nonselective species. Hence, we propose the carbonate species-activated hydrogen peroxide (carbonate species/H2O2) process wherein the selective oxidant (peroxymonocarbonate ion, HCO4–) and selective reductant (hydroperoxide anion, HO2–) controllably coexist by manipulation of reaction pH. Taking 2-chloropyridine (Cl–Py) as an example, HCO4– first induces Cl–Py into pyridine N-oxidation intermediates, which then suffer from the nucleophilic dechlorination by HO2–. The obtained dechlorination efficiencies in the carbonate species/H2O2 process (32.5–84.5%) based on the cooperation of HCO4– and HO2– are significantly higher than those in the HO2–-mediated sodium hydroxide/hydrogen peroxide process (0–43.8%). Theoretical calculations confirm that pyridine N-oxidation of Cl–Py can effectively lower the energy barrier of the dechlorination process. Moreover, the carbonate species/H2O2 process exhibits superior anti-interference performance and low electric energy consumption. Furthermore, Cl–Py is completely detoxified via the carbonate species/H2O2 process. More importantly, the carbonate species/H2O2 process is applicable for efficient dehalogenation of halogenated pyridines and pyrazines. This work offers a simple and useful strategy to enhance the dehalogenation efficiency of halogenated organics and sheds new insights into the application of the carbonate species/H2O2 process in practical environmental remediation.
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
Catalysts
·
2020
·Vol. 10
·期 4
·377
·
IF 3.52
Wei Yu,Wenfeng Han,Yongnan Liu,Jiaqin Lu,Hong Yang,Bing Liu,Haodong Tang,Aimin Chen,Ying Li
BaClxFyas well as BaF2and BaClF catalysts were prepared by solid-state reaction at room temperature with Ba(OH)2as the precursor and NH4F/NH4Cl as the F and Cl sources. The catalysts were applied for the dehydrochlorination of 1-chloro-1,1-difluoroethane to vinylidene fluoride at 350 °C. The industrial manufacture of vinylidene fluoride (VDF) is carried out at 600–700 °C, whereas the BaClxFycatalysts provided a promising pathway to produce VDF at much lower temperatures. Unfortunately, the selectivity of VDF over BaF2decreased from 94% to 84% along with the deactivation of the BaF2catalyst monotonically. In the presence of small amounts of Cl in BaF2, stabilized selectivity was achieved. Over BaCl0.05F0.95, BaCl0.1F0.9and BaCl0.25F0.75, no decrease in VDF selectivity was observed. Clearly, the presence of small amounts Cl during solid-state preparation inhibited the growth of BaF2crystalline significantly. Far smaller particles were achieved. The particle size, or more precisely, the crystal size of the barium catalyst played a major role in the catalytic performance. In addition to the crystal growth, the presence of small amounts of Cl during catalyst preparation changed the chemical state of Ba, and therefore the adsorption and activation of the C–Cl bond for HCFC-142b were altered.Keywords:barium chlorofluoride;catalytic pyrolysis;barium fluoride;dehydrochlorination;1-chloro-1,1-difluoroethane;vinylidene fluoride
研究领域:
化学工程
·
材料科学
·
催化
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2018
·
IF 4.61
Bo Liu,Hao Zhang,Qi Lu,Guanghe Li,Fang Zhang
To address the challenges of low hydrodechlorination efficiency by non-noble metals, a Cu Ni bimetallic cathode with nanostructured copper array film was fabricated for effective electrochemical dechlorination of trichloroethylene (TCE) in aqueous solution. The Cu Ni bimetallic cathodes were prepared by a simple one-step electrodeposition of copper onto the Ni foam substrate, with various electrodeposition time of 5/10/15/20 min. The optimum electrodeposition time was 10 min when copper was coated as a uniform nanosheet array on the nickel foam substrate surface. This cathode exhibited the highest TCE removal, which was twice higher compared to that of the nickel foam cathode. At the same passed charge of 1080C, TCE removal increased from 33.9 ± 3.3% to 99.7 ± 0.1% with the increasing operation current from 5 to 20 mA cm −2 , while the normalized energy consumption decreased from 15.1 ± 1.0 to 2.6 ± 0.01 kWh log −1 m −3 . The decreased normalized energy consumption at a higher current density was due to the much higher removal efficiency at a higher current. These results suggest that Cu Ni cathodes prepared by simple electrodeposition method represent a promising and cost-effective approach for enhanced electrochemical dechlorination.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
GREEN CHEMISTRY
·
2025
·
IF 9.2
Junfei Zhang,Yun Zou,Shengyang Tao
Polyvinylidene chloride (PVDC) is widely employed in packaging and construction materials due to its high chemical stability and excellent barrier performance. However, its persistent nature results in significant environmental accumulation, posing ecological risks. Conventional treatment methods often generate highly toxic byproducts, leading to the waste of chlorine resources. To address these challenges, this study introduces a novel electrochemical approach for the resource recovery of PVDC. Using PVDC as a chlorine source and di(2-ethylhexyl)phthalate (DEHP) as an electron mediator, we achieved the coupling of electrochemical dechlorination of PVDC with the synthesis of β-chloroalcohols. The halogenated alcohol derivatives were obtained in yields up to 76%, with good substrate versatility encompassing styrene derivatives bearing various functional groups as well as certain cyclic olefins. Moreover, the methodology was successfully applied to commercially available PVDC products, affording the target compounds in approximately 50% yield. This work offers a novel strategy for the sustainable recycling and valorization of plastic waste.
✓ 已验证
DOI
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2022
·Vol. 331
·期 12
·5641-5648
·
IF 1.754
Smolenski Valeri,Novoselova Alena,Yan Yongde,Xue Yun,Ma Fuqiu
The equilibrium potentials of Me(III)/Me (Me = Dy, U) couples and the double Me–Ga, Me–Cd alloys vs. Cl − /Cl 2 reference electrode were measured at the temperature range 673–973 K in molten LiCl–KCl–CsCl eutectic by open-circuit potentiometry. The apparent standard potential and the base thermodynamic properties of alloys were determined. Separation factor for Dy/U couple was calculated on gallium and cadmium electrodes. In addition, it was found that the application of gallium electrodes has a significant advantage over cadmium electrodes in the process of electrochemical separation of uranium and dysprosium.
研究领域:
材料科学
·
核能工程
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2023
·
IF 11.4
Xiaokun Liu,Lian Zhang,Rui Shen,Qihong Lu,Qinglu Zeng,Xiaojun Zhang,Zhili He,Simona Rossetti,Shanquan Wang
Chloroethenes (CEs) as common organic pollutants in soil could be attenuated via abiotic and biotic dechlorination. Nonetheless, information on the key catalyzing matter and their reciprocal interactions remains scarce. In this study, FeS was identified as a major catalyzing matter in soil for the abiotic dechlorination of CEs, and acetylene could be employed as an indicator of the FeS-mediated abiotic CE-dechlorination. Organohalide-respiring bacteria (OHRB)-mediated dechlorination enhanced abiotic CEs-to-acetylene potential by providing dichloroethenes (DCEs) and trichloroethene (TCE) since chlorination extent determined CEs-to-acetylene potential with an order of trans-DCE > cis-DCE > TCE > tetrachloroethene/PCE. In contrast, FeS was shown to inhibit OHRB-mediated dechlorination, inhibition of which could be alleviated by the addition of soil humic substances. Moreover, sulfate-reducing bacteria and fermenting microorganisms affected FeS-mediated abiotic dechlorination by re-generation of FeS and providing short chain fatty acids, respectively. A new scenario was proposed to elucidate major abiotic and biotic processes and their reciprocal interactions in determining the fate of CEs in soil. Our results may guide the sustainable management of CE-contaminated sites by providing insights into interactions of the abiotic and biotic dechlorination in soil.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2014
·
IF 4.058
Bo Yang,Jiaxing Zhang,Yunfei Zhang,Shubo Deng,Gang Yu,Jinhua Wu,Hong Zhang,Jianhong Liu
The low-cost Al–Ni alloy particles could achieve high dechlorination activity for 2-chlorophenol (2-CP) with the addition of tetrasodium EDTA (EDTA-4Na) in this study. The species of chelating agent, pH values, and the dosages of chelating agent were investigated for their effects on dechlorination efficiency of 2-CP in solution. EDTA-4Na presented the highest promoting effect for Al–Ni alloy in dechlorination process compared with other chelating agents, which is closely correlated with the conditional stability constant ( K f ′ ) of chelates formed. The optimized result showed that 0.389 mM of 2-CP was completely dechlorinated into phenol using 10 g L −1 of Al–Ni alloy and 10 mM of EDTA-4Na at initial pH 11.0 within 45-min reaction. Recycling tests of the alloy particles showed that Al–Ni alloy coupling with EDTA in aqueous solution exhibited high dechlorination activity and stability before being exhausted. The maintenance of Al–Ni alloy activity for dechlorination was mainly attributed to the promoting effect of EDTA-4Na on Al corrosion, the inherent structure of alloy with Ni crystal homogeneously dispersing into Al substrate, and the change of its surface morphology with more active sites formed by EDTA corrosion.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Communications Earth & Environment
·
2022
·Vol. 3
·期 1
·1-10
·
IF 7.29
Li Dongdong,Zhao Yu-Yan Sara,Meslin Pierre-Yves,Vals Margaux,Forget François,Wu Zhongchen
The high perchlorate (ClO 4 − ) to chloride (Cl − ) ratios observed at the Phoenix landing site, northern polar region of Mars, have been puzzling since detection. However, a lack of understanding of perchlorate-chloride-water systems under cryogenic conditions makes it difficult to assess ClO 4 − /Cl − ratios during deliquescence-related processes. Here we quantitatively evaluate ClO 4 − /Cl − fractionation in deliquescence-induced brines of magnesium- and calcium-perchlorate-chloride salt mixtures under subzero conditions, by measuring solubility data and constructing temperature-dependent thermodynamic models. We find that under specific relative humidity (RH) and temperature ( T ) conditions, deliquescence of perchlorate-chloride mixtures may form brines with fractionated ClO 4 − /Cl − signatures. Appropriate RH -T , water-limited conditions, and aeolian processes are required to produce and preserve the elevated ClO 4 − /Cl − signatures in soils. Under the present climate, the north polar region can support ClO 4 − /Cl − fractionation and potentially enrich perchlorate for longer periods on global Mars. This highlights the uniqueness of Mars’ arctic environment and its implications for modern habitability.
研究领域:
地球科学
·
化学
✓ 已验证
DOI
高影响因子
Environmental Chemistry
·
2012
·Vol. 9
·期 6
·558-563
·
IF 2.57
Lei Wu,Xuefeng Hu,Lei Wu,Xuefeng Hu
Environmental context Aromatic amines are widely used chemicals, which show enhanced toxicity and longer environmental persistence when halogenated. We investigated the chlorination of aniline in seawater and in natural aqueous solutions containing Fe3+ and Cl–, under simulated sunlight irradiation. The results increase our understanding of the transformation pathway of typical nitrogen-containing aromatic contaminants in the environment. Photochlorination of aniline was observed in aqueous solutions containing dissolved FeIII and chloride ions under simulated solar light irradiation. Effects of O2, Cl–, Fe3+ and pH on the formation of chloroanilines (CAs) were investigated. para-chloroaniline (4CA) was identified as the main chlorinated product. The formation of 4CA is enhanced with increased concentrations of Cl– or Fe3+, and decreased pH, whereas oxygen plays a negligible role in the process. The results indicate that, Cl• is formed mainly by the photodissociation of FeCl2+–FeCl2+ complexes, and reacts with Cl– to produce Cl2•–. Aniline is then oxidised by Cl2•– into an anilino radical cation, which further reacts with Cl2•– to generate CAs. The photochlorination of aniline in natural seawater was also observed. Other phototransformation products of aniline were detected and a transformation pathway was proposed. This work provides evidence for the photochemical chlorination path of aniline-based aromatic amines in aqueous solutions.
研究领域:
环境科学
·
化学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Yuan Chen,Yuancai Chen,Jianbo Jia,Bing Yan
The present study focuses on the successful preparation of microbial palladium nanoparticles (Pd-NPs). The even distribution of Pd in the periplasmic space of B. megaterium Y-4 cells is characterized using a transmission electronic microscopy (TEM) and scanning electron microscope (SEM). X-Ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) revealed the domination of Pd (0) in Pd-NPs. The microbial Pd-NPs were selected to detoxify triclosan (TCS). Liquid chromatography-mass spectrometry (LC-MS) was used to analyze the intermediate products of dechlorination and oxidization. Free radicals quenching and 5,5-dimethyl-1-pyrroline N-oxide (DMPO) capturing experiments confirmed the crucial contribution of atomic H• and O 2 ·– to TCS degradation. Besides, TCS degradation by microbial Pd-NPs could alleviate the cytotoxicity of TCS polluted water. Meanwhile, great circulating utilization of microbial Pd-NPs was obtained in degrading TCS. Corresponding findings in the present study could provide new insight into the role of microbial Pd-NPs in detoxifying pollutants.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2024
·
IF 5.6
Yuxin Tu,Heming Li,Yuandi Xue,Wen Xie,Canrong Chen,Yanhui Zhong,Zian Lin,Zongwei Cai
Triclosan (TCS), triclocarban (TCC), and chlorophenols (CPs) are broad-spectrum antibacterials widely used in dermatological and oral hygiene products, which could induce severe liver and intestine injuries. Hence, it is essential to establish a rapid and sensitive method to monitor TCS, TCC, and CPs in various organisms. In this work, fluorine-functionalized covalent organic framework (COF–F) was prepared by using 4,4′,4''-(1,3,5-triazine-2,4,6-triyl)tri-aniline and 2,3,5,6-tetrafluoroterephthalaldehyde as two building units and employed as a solid phase microextraction (SPME) probe for the extraction of TCS, TCC and CPs. The COF–F possessed excellent hydrophobicity, a large specific surface area (1354.3 m 2 g −1 ) and high uniform porosity (3.2 nm), which facilitated high selectivity and adsorption properties towards TCS, TCC, and CPs. Therefore, the as-prepared COF–F-SPME in combination with electrospray ionization mass spectrometry has been developed to provide fast and ultrasensitive detection of TCS, TCC, and CPs in biological samples. The established method demonstrated satisfactory linear ranges (0.01–100.00 μg L −1 ) and low limits of detection (0.003–0.040 μg L −1 ) for TCS, TCC and CPs. The developed method could be successfully applied to detect TCS, TCC and CPs in the liver and kidney tissues of mice, demonstrating the potential for the detection of chlorinated aromatic pollutants in the biological samples.
研究领域:
分析化学
·
环境科学
·
生物医学
✓ 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）