ENVIRONMENTAL TECHNOLOGY
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2025
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IF 2
Chunyun Gu,Jiayi An,Shuyu Liu,Feng Xiong,Wei Zhou,Liting Tian,Yuruo Wan,Qian Wu,Jie Ma
Oxidants used in the ISCO technology usually require activation by activators to degrade contaminants. However, this study investigated degradation of 15 typical halogenated hydrocarbons by five common ISCO oxidants (PS, PMS, H2O2, KMnO4, SPC) without activation in both pure water and real groundwater. Unactivated PS could degrade 14 halogenated hydrocarbons, excluding tetrachloromethane. Unactivated KMnO4 could degrade chlorinated alkenes. Unactivated SPC could degrade 1,1,2,2-tetrachloroethane by a base-promoted second-order elimination reaction. PMS, H2O2, and SPC could be activated by the natural matrix constituents in groundwater, enabling them to degrade some halogenated hydrocarbons. Among the 15 halogenated hydrocarbons studied, only tetrachloromethane cannot be degraded by any oxidant due to its carbon being in its highest oxidation state. The experimental data in the pure water indicate that the overall degradation rate of unactivated PS for chlorinated alkanes increased with increases in the number of chlorine substituents. The degradation rate of unactivated PS for halogenated hydrocarbons decreased with increases in the carbon chain length. Chlorinated alkenes are more easily degraded than chlorinated alkanes while chlorinated alkanes are more readily degraded than brominated alkanes. The degradation rate of unactivated KMnO4 for chlorinated alkenes decreased with increases in the number of chlorine substituents and decreased with increases in the carbon chain length. Overal, results of this study show that unactivated ISCO is a promising and environmentally friendly in-situ remediation technology that may be a good candidate for the remediation of contaminated sites by halogenated hydrocarbons.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2017
·
IF 3.091
Wenfeng Li,Yingjie Li,Yong Chen,Qingnan Liu,Yingzhou Lu,Hong Meng,Chunxi Li
Carbon-based materials are a kind of promising sorbent for the desulfurization of fuel oils, especially for polycyclic aromatic sulfur heterocycles (PASHs), and development of new sorbents is of great significance. In this paper, six alkynyl carbon materials (ACM-1 to ACM-6) were prepared for the first time through mechanochemical reaction of calcium carbide with six full halogenated hydrocarbons, i.e., CCl4, C2Cl6, C2Cl4, C6Cl6, C6Br6, and C14H4Br10, respectively. Their carbon content and specific surface areas (SSAs) were analyzed, and their adsorption performance for thiophenic sulfurs was studied. The ACMs are mesoporous materials with relatively high SSAs and favorable adsorptive performance for PASHs with the order of DBT > BT > 3-MT. Their adsorptivity is virtually consistent with the SSA values and follows the order of ACM-6 > ACM-5 > ACM-4 > ACM-1 > ACM-3 > ACM-2. ACM-6 has the highest SSA (712 m2 g–1) and saturated adsorbance of 21.1 mg-S·g–1 for DBT in octane, as well as 6 mg-S·g–1 for real diesel. As a whole, ACM-6 represents the best ADS sorbent among all mesoporous carbon materials and may be applicable for real oils after some further modification.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2021
·
IF 7.92
Zhi-Feng Jiao,Ya-Ming Tian,Xiao-Ning Guo,Udo Radius,Holger Braunschweig,Todd B. Marder,Xiang-Yun Guo
A highly efficient photocatalytic protocol for borylation of alkyl bromides and chlorides with graphene supported Cu/Pd alloy nanoparticles as a heterogeneous catalyst is reported. This photocatalytic system operates with visible light in air, providing a wide range of primary and secondary alkyl halides with B 2 pin 2 or B 2 neop 2 in high yields at low temperatures, thereby demonstrating its broad utility and functional group tolerance. The high performance is attributed to a synergistic effect of localized surface plasmon resonance (LSPR) of Cu and charge transfer from Cu to Pd due to the alloy surface charge heterogeneity. Transfer of energetic electrons from Pd to electrophilic alkyl halides lead to the formation of the alkyl radicals, which quickly react with a nucleophilic adduct of a diboron compound with base adsorbed on the positively charged Cu sites to form the corresponding borylation product.
研究领域:
有机化学
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材料科学
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催化化学
✓ 已验证
DOI
高影响因子
Scientific Reports
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2017
·Vol. 7
·期 1
·1-9
·
IF 4.259
He Shichong,Zhu Lizhong
Sorptive landfill liners can prevent the migration of the leachate pollutants. However, their sorption ability will decrease over time. A method should be developed to maintain the sorption ability of landfill liners. In this study, we combined cetyltrimethylammonium bromide-bentonite (CTMAB-bentonite) and zero-valent iron (ZVI) to develop a self-cleaning liner that can retain its sorption ability for a long period. Batch experiments and calculation simulations were employed to analyse the sorption ability of this liner material and the ecological risk of halogenated hydrocarbons. The results showed that CTMAB-bentonite could sorb halogenated hydrocarbons well, with saturated sorption capacities ( Q
m ) of 10.2, 14.5, 6.69, 18.5, 29.4, and 49.7 mg·g -1 for dichloroethane (DCA), trichloroethane (TCA), dichloroethene (DCE), trichloroethylene (TCE), tetrachloroethylene (PCE), and 1,3- dichloropropene (1,3-DCP), respectively. Using the mixture of 0.5 g iron and 0.5 g CTMAB-bentonite could dramatically increase the removal efficiency of DCE, TCE, and PCE. The reaction with ZVI did not change the structure of CTMAB-bentonite and its sorption ability remained consistent. Calculation results suggested that the self-cleaning landfill liner would dramatically decrease the hazard index (HI) of the eluate. However, the humic acid and salt in leachate would cause a reduction in the removal of halogenated hydrocarbons.
研究领域:
环境科学
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污染控制
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产品关联
DOI
PubMed
高影响因子
ChemCatChem
·
2016
·Vol. 8
·期 8
·1557-1563
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IF 4.724
Qingping Ke,Mingzhou Wu,Chao Wang,Guanzhong Lu
Graphical Zeolite my fire : Ullmann coupling reactions of phenols with nitro-substituted aryl halides are catalyzed by rare-earth-doped mesoporous AlPO-5 zeolites in the absence of ligands. The LaAlPO-5-MAlPO-5-M zeolite is an excellent catalyst for Ullmann coupling reactions of phenols and nitro-substituted aryl halides. Mesoporous LaAlPO-5 has an excellent stability and recyclability in the Ullmann coupling of p -X-nitrobenzene (X=Cl, Br, and I) with 2-naphthol. Heterogeneous catalytic reactions of aromatic organic molecules over zeolite catalysts present many challenges because of the shape selectivity of the micropores of conventional zeolites that limits the diffusion of aromatic molecules. Herein, Ullmann coupling reactions of phenols with nitro-substituted aryl halides were catalyzed by rare-earth-doped mesoporous AlPO-5 zeolites in the absence of ligands. The AlPO-5-MAlPO-5-M zeolites had a pure AFI structure and consisted of spherical particles assembled by nanofibers. The rare-earth elements were highly dispersed in the AlPO-5-MAlPO-5-M samples. The LaAlPO-5-MAlPO-5-M zeolite is an excellent catalyst for Ullmann coupling reactions of phenols and nitro-substituted aryl halides. Mesoporous LaAlPO-5 has an excellent stability and recyclability in the Ullmann coupling of p -X-nitrobenzene (X=Cl, Br, and I) with 2-naphthol. These results are important in the exploration of attractive Ullmann coupling reactions and in the development of mesoporous zeolite catalysts for other organic reactions.
研究领域:
有机化学
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催化化学
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产品关联
DOI
高影响因子
POLYMER
·
2023
·
IF 4.6
Jun Zhang,Rongye Guo,Yubing Li,Hanyu Ma,Junkun Tang,Zuozhen Liu,Farong Huang
Poly(1,2,3-triazolium) (PTAM) is a kind of self-healing adhesive based on dynamic reversible covalent 1,2,3-triazolium, which is formed through the reaction of halogenated hydrocarbon and 1,2,3-triazole and plays an important role in the properties of PTAM. Therefore, it is valuable to understand the effect of halogenated hydrocarbon crosslinkers on the properties of PTAM. A series of PTAM adhesive with different crosslinkers have been prepared. The reactivity between halogenated hydrocarbon and 1,2,3-triazole was different. Crosslinkers with longer chain, iodine substituted and aromatic structure improved the adhesive property of PTAM adhesive joints, which was up to 17 MPa. The first self-healing efficiency of PTAM adhesive joints with aliphatic bromine crosslinkers reached more than 100% and the maximum cycle times of them was more than 9 before failure. The self-healing properties of PTAMs depend on the segment motion and anti-thermal oxygen aging of PTAMs. These results provide some insights for the structural design of self-healing adhesive and dynamic covalent materials.
研究领域:
材料科学
·
化学工程
✓ 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）