MATERIALS CHEMISTRY AND PHYSICS
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2020
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IF 3.408
Longfei Qin,Zuoyi Xiao,Shangru Zhai,Shifu Wang,Hui Lv,Wensha Niu,Zhenyu Zhao,Qingda An
N-doped porous carbons have recently drawn increasing attention for energy storage devices due to large surface area, various N configurations, and environment friendliness. In this work, we have reported a defect-rich N-doped porous carbon (DNPC) derived from alginate via the combined processes of crosslinking sodium alginate (SA) by CaCO 3 hard template, a high-temperature carbonization , as well as HNO 3 etching for high-performance supercapacitors (SCs). The specific surface area and pore volume of the optimized DNPC sample are 1117 m 2 g −1 and 1.01 cm 3 g −1 , respectively. The effects of preparation parameters on structural features and electrochemical properties , including the mass ratios of CaCO 3 to SA, heating temperatures, and dosages of HNO 3 , are extensively investigated. Thanks to the advantages of developed porous structure, controllable N configurations, and large specific surface area, the DNPC1 sample displays superior specific capacitance (296 F g −1 ) and outstanding capacitance retention of 91% after 10000 cycles at 5 A g −1 . Additionally, a symmetrical SC with DNPC1 delivers energy densities of 12.9 and 18.9 W h kg −1 in KOH and Na 2 SO 4 electrolytes, respectively. This study presents a facile way to fabricate the N-doped porous carbons with controllable N configurations for energy storage devices.
研究领域:
材料科学
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能源存储
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DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2023
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IF 2.6
Shuyang Shi,Baozhong Ma,Shuang Shao,Yongqiang Chen,Chengyan Wang
An original technology named HNO3 pressure leaching has been proposed by our team to leach Al from coal gangue and fly ash. Although the preliminary separation of Al and Fe had been achieved during leaching, a small amount of Fe impurity was still unavoidably dissolved into the leach liquor. To obtain pure Al2O3 during subsequent pyrolysis, it is imperative to synchronously remove Fe3+ during the crystallization of Al(NO3)3·9H2O. Herein, the phase equilibria of the Al(NO3)3–Fe(NO3)3–H2O(−HNO3) system at 25–40 °C and 0–8.12 mol kg–1 of HNO3 molality were investigated. The results indicated that the ternary system was a simple cosaturated type consisting of an immutable point, two univariate curves, and two crystallization regions. Notably, the solubility and crystallization region of Al(NO3)3·9H2O were barely impacted by acidity, while the opposite was true for Fe(NO3)3·9H2O. This finding was instructive for the crystallization of Fe(NO3)3·9H2O from the liquor with high Fe and low Al. Moreover, a high crystallization yield could be obtained at low temperatures. Finally, an appropriate crystallization procedure was provided. This study is expected to provide basic data and theoretical support for the crystallization and separation of mixed nitrates containing Al and Fe.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
HYDROMETALLURGY
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2013
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IF 2.169
Junlian Wang,Shengming Xu,Linyan Li,Jing Li
Efficient new extractant design relies on systematic structure–property studies. However, systematic structure–property research on extractants of organic phosphinic acids is far from sufficient. To make up for this deficiency, twelve organic phosphinic acid extractants (including nine dialkylphosphinic acids, two dicycloalkylphosphinic acids and one diarylphosphinic acid) were synthesized with free-radical-addition-reaction method and Grignard-reaction method. Reaction rules, advantages and disadvantages of these two methods were discussed respectively. The extraction ability and separation performance of the synthesized organic phosphinic acids for Tm, Yb and Lu from HNO 3 solutions were evaluated and compared. For dialkylphosphinic acids the nearer the branched chain moved to P atom, the more reduction generated on the extraction ability. Dialkylphosphinic acids without branched chain in α-C or β-C (e.g. HYY-3, HYY-5, HYY-7 and HYY-9) exhibited strong extraction ability as P507. On the contrary, dialkylphosphinic acids with branched chain in α-C (e.g. HYY-4, HYY-8) and dicyclohexylphosphinic acids exhibited poor extraction ability as Cyanex 272. New compound Di-(2,3-dimethylbutyl)-phosphinic acid (HYY-2) exhibited good extraction ability and separation performance and its separation factors of Lu/Yb, Yb/Tm and Lu/Tm were 1.42, 3.10 and 4.40 respectively, apparently superior to Cyanex 272 (β Lu/Yb = 1.31, β Yb/Tm = 3.25, β Lu/Tm = 4.26).
研究领域:
化学
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材料科学
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产品关联
DOI
高影响因子
WATER RESEARCH
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2024
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IF 11.4
Yurong Wu,Guangliang Liu,Xiaoquan Liu,Yuxiang Mao,Yingying Guo,Yanwei Liu,Liuchao Zhu,Yongguang Yin,Yong Cai,Guibin Jiang
Ethylmercury (EtHg), similar to methylmercury (MeHg), is highly neurotoxic and bioaccumulative. Although recent studies suggested its occurrence in natural soils and sediments, the common propylation derivatization for EtHg analysis might generate EtHg artifacts, potentially leading to its overestimation in environmental samples. Furthermore, the extensive environmental prevalence of EtHg remains unverified, keeping its importance largely uncertain. This study investigated the formation of EtHg artifacts during propylation derivatization, evaluating artifacts formation and recoveries under different extraction methods with real samples, and confirmed the widespread occurrence of EtHg in Chinese wetlands. EtHg artifacts were obviously present during the propylation derivatization and strongly dependent on the levels of Hg 2+ (0.1–10 ng) in the derivatization solution (R² = 0.99), accounting for 1.38–2.14% of Hg 2+ . CuSO 4 -HNO 3 CH 2 Cl 2 extraction (effectively removing Hg 2+ ) combined with propylation derivatization offers excellent recovery (81–86%) and low artifacts (< LOD: 1.98 × 10 −4 ng/g) for EtHg measurement in soils/sediments, with results aligning with those from online solid phase extraction-high performance liquid chromatography-inductively coupled plasma mass spectrometry (R 2 = 0.99). Additionally, we observed the occurrence of EtHg in soil and sediment samples across 14 Chinese wetlands, with concentrations varying from 6.08 to 171 pg/g, similar to MeHg concentrations at some sites. EtHg positively correlates with MeHg, total Hg, and total organic carbon across all samples, indicating a possible biological formation. These findings help better understand and predict the prevalence of EtHg in wetlands and its key role in environmental Hg cycle.
研究领域:
环境科学
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分析化学
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生态毒理学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2026
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IF 10.6
Chenguang Zhang,Xiaofei Xu,Chuancheng Dongye,Chenglong Yuan,Mengran He,Xiuli Shen,Xincheng Chen,Zhihe Li,Shaoqing Wang
An Fe and HNO 3 co-modified adsorbent was developed for efficient BPA removal from water. • Fe/Ads-1N achieved a high adsorption capacity of 44.94 mg/g for BPA. • Pyrolysis regeneration enabled recovery of phenol and methane-rich gas from BPA-loaded adsorbents. • DFT revealed BPA interactions with Fe 3 O 4 active sites and oxygen-containing groups. • A comprehensive adsorption mechanism was proposed based on combined experimental and theoretical results. Bisphenol A (BPA), a typical endocrine-disrupting pollutant, poses a threat to human health. In this study, an Fe and HNO 3 co-modified adsorbent was synthesized through the co-pyrolysis of lignin and spent bleaching clay for BPA removal. The effects of initial pollutant concentration, pH, coexisting substances, and regeneration cycles on adsorption performance were systematically investigated. The results showed that 1 M HNO 3 treatment enhanced Fe dispersion, and introduced abundant oxygen-containing functional groups. The Fe/Ads-1N exhibited a maximum theoretical adsorption capacity of 44.94 mg/g for BPA. DFT calculations revealed the formation of stable coordination complexation interactions between the electron-rich phenolic hydroxyl oxygen of BPA and the electron-deficient Fe active sites, as well as the role of oxygen-containing functional groups as excellent hydrogen bond donors/acceptors. After three regeneration cycles, Fe/Ads-1N retained an adsorption capacity of 25.1 mg/g. Furthermore, 49.7 mg/g of phenol and methane-rich gas were recovered during the regeneration process, demonstrating the potential for converting pollutants into resource recovery. Pyrolysis regeneration of spent adsorbents offered higher stability and lower per-run operating costs compared to solvent regeneration. This study provides a viable strategy for the high-value utilization of pyrolysis residues and the efficient removal and recovery of BPA from aqueous systems. Download: Download high-res image (223KB) Download: Download full-size image
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DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
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2019
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IF 2.29
Zhan-Ping Qiao,Meng-Yao Su,Yuan-Lin Dang,Qi-Chao Yang
The phase diagrams of the Mg(NO 3 ) 2 –Ln(NO 3 ) 3 (Ln = Nd, Sm, Eu, Tb)–HNO 3 –H 2 O systems in the (∼20%) HNO 3 regions at T = 298.15 K were determined by using an isothermal solution saturation method. The Schreinemaker’s wet residues method was used to determine the compositions of solid-phases. Both Mg(NO 3 ) 2 –Nd(NO 3 ) 3 –HNO 3 –H 2 O and Mg(NO 3 ) 2 –Sm(NO 3 ) 3 –HNO 3 –H 2 O systems are complicated with three equilibrium solid phases Mg(NO 3 ) 2 ·6H 2 O, Mg 3 Ln 2 (NO 3 ) 12 ·24H 2 O and Ln(NO 3 ) 3 ·6H 2 O (Ln = Nd, Sm). But the systems Mg(NO 3 ) 2 –Eu(NO 3 ) 3 –HNO 3 –H 2 O and Mg(NO 3 ) 2 –Tb(NO 3 ) 3 Tb–HNO 3 –H 2 O are simple eutonic type. The two new solid-phase compounds Mg 3 Nd 2 (NO 3 ) 12 ·24H 2 O and Mg 3 Sm 2 (NO 3 ) 12 ·24H 2 O are congruently soluble in an average medium of ∼20 mass % HNO 3 , and they were identified and characterized by the methods of powder X-ray diffraction, X–ray diffraction single crystal structure analysis, and thermogravimetric/differential thermogravimetric. The XRD diffraction patterns for the two new solid-phase compounds are identical due to their isomorphic structure. They belong to hexagonal systems, with space group R 3 . For Mg 3 Nd 2 (NO 3 ) 12 ·24H 2 O, a = b = (1.0993 ± 0.0005) nm, c = (1.7211 ± 0.0007) nm, V = (1.8012 ± 0.0013) nm 3 , D c = (4.2532 ± 0.0024) g·cm −3 , Z = 3; for Mg 3 Sm 2 (NO 3 ) 12 ·24H 2 O, ( a = b = 1.1198 ± 0.0004) nm, c = (1.7257 ± 0.0006) nm, V = (1.8742 ± 0.0011) nm 3 , D c = (4.1201 ± 0.0012) g cm −3 , Z = 3. The standard molar enthalpies of solution of the compounds Mg 3 Nd 2 (NO 3 ) 12 ·24H 2 O and Mg 3 Sm 2 (NO 3 ) 12 ·24H 2 O in water (aq) were measured to be (101.26 ± 0.77) kJ mol −1 and (80.27 ± 0.81) kJ mol −1 , and their standard molar enthalpies of formation were calculated to be – (12214.13 ± 2.5) kJ mol −1 and – (12183.6 ± 2.5) kJ mol −1 , respectively.
研究领域:
化学
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物理化学
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材料科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2019
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IF 8.355
Yan Cui,Lei Qin,Weiwei Kang,Jinghong Ma,Yongzhen Yang,Xuguang Liu
Magnetic carbon nanospheres (MCNSs) dotting with Fe 3 O 4 nanoparticles were synthesized by a simple solvothermal method. Furtherly, KOH activation and HNO 3 acidification of MCNSs were carried out to tune surface structure and property of MCNSs for the sake of adsorption improvement. The results show that both MCNSs and modified MCNSs (MCNSs-KH) have magnetic properties, and can be used as adsorbents for rapid separation and reutilization towards quinoline in coking wastewater. After KOH activation and HNO 3 acidification, the saturated adsorption capacity of MCNSs-KH is improved to 297.21 mg g −1 , much better than that of MCNSs (99.43 mg g −1 ). According to BET and NH 3 -TPD characterizations, KOH activation introduced a large number of pore structures, which significantly increased the specific surface area of MCNSs; HNO 3 acidification further increased the surface acidity of MCNSs, especially C O functional group, which promoted the acid–base interaction with weakly basic quinoline. From the results of adsorption kinetics, isotherm and thermodynamics, the spontaneous and exothermic adsorption process conformed to pseudo-second-order and Langmuir–Freundlich models better.
研究领域:
材料科学
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环境工程
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化学工程
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纳米技术
✓ 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）