Materials
·
2021
·Vol. 14
·期 9
·2224
·
IF 3.623
Xinzhe Sun,Peng Guo,Yuanyuan Sun,Yuqian Cui
Lanthanun oxide (La2O3) is a lanthanum chemical compound incorporates a sensible anionic complexing ability; however, it lacks stability at a low pH scale. Biochar fibers will give the benefit of their massive space and plethoric uses on the surface to support a metal chemical compound. Herein, wet spinning technology was used to load La3+onto sodium alginate fiber, and to convert La3+into La2O3through carbonization. The La2O3-modified biochar (La-BC) fiber was characterized by SEM, XRD and XPS, etc. An adsorption experiment proved that La-BC showed an excellent adsorption capacity for chromates, and its saturation adsorption capacity was about 104.9 mg/g. The information suggested that the adsorption was in step with both the Langmuir and Freundlich models, following pseudo-second-order surface assimilation mechanics, which showed that the Cr (VI) adsorption was characterized by single-phase and polyphase adsorption, mainly chemical adsorption. The thermodynamic parameters proved that the adsorption process was spontaneous and endothermic. The mechanistic investigation revealed that the mechanism of the adsorption of Cr (VI) by La-BC may include electrostatic interaction, ligand exchange, or complexation. Moreover, the co-existing anions and regeneration experiments proved that the La-BC is recyclable and has good prospects in the field of chrome-containing wastewater removal.Keywords:wet spinning;lanthanum oxide;biochar;chromate;adsorption
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
TRIBOLOGY LETTERS
·
2022
·Vol. 70
·期 2
·1-16
·
IF 3.327
Wang Peng,Gao Peng,Ma Lin,Wen Ping,Han Yunyan,Dong Rui,Fan Mingjin
In this paper, four ionic liquids based on chromotropate (CAILs) were prepared and applied to heighten the tribological performance of aqueous system on different metal friction contacts. Taking for the potential choice for water-based lubricating additive, CAILs exhibited excellent water solubility and corrosion resistance. Tribological results showed that the CAILs, especially the phenolic hydroxyl group decorated samples (TsnN 4444 and TsnP 4444 ), demonstrating extremely effective lubricating properties with the efficient friction and wear descent (69% and 83% for Fe, 47% and 94% for Cu, 74% and 69% for Al, respectively). Especially, the excellent load-carrying capacity was also presented with the highest P B (833 N) and P D (1568 N) values for TsnP 4444 . It is speculated that the CAIL molecular adsorption on the interface and further generation of tribochemical films are beneficial for their lubricating effects, resulting from the systematic discussion and analysis of CA, QCM, SEM, XPS, and FIB-TEM tests. However, TsN 4444 and TsP 4444 showed less effective lubricating performances and poor load-carrying capacities due to tribocorrosion of hydroxyl groups at the interface. Graphical Abstract
研究领域:
材料科学
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机械工程
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DOI
高影响因子
OPTICAL MATERIALS
·
2019
·
IF 2.687
Xiaoqing Guo,Shuangju Song,Xue Wang,Xue Jiang,Wenqing Lv,Xiaoya Yu,Yuanyuan Han,Liyong Wang
A novel inorganic dual-functional fluorescent chemosensors CaMoO 4 :Eu 3+ has been prepared via solid-state reaction by the assistance of gum arabic (GA). The fluorescence of as-prepared CMO:Eu 3+ was selectively quenched by Fe 3+ and Cr 2 O 7 2− ions in aqueous, resulting in the simultaneous detection of Fe 3+ and Cr 2 O 7 2− ions. The F − anions can recover the fluorescence when Fe 3+ quenching the fluorescence at 615 nm. Moreover, CMO:Eu 3+ displayed high sensitivity for Fe 3+ and Cr 2 O 7 2− assay and the detection limits were 8.26 and 4.78 μM, respectively. The fluorescence quenching mechanism was ascribed to the competitive adsorption between CMO:Eu 3+ and targets. Results indicated that CMO:Eu 3+ could be a promising candidate in Fe 3+ and Cr 2 O 7 2− ions assay in environmental systems.
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
SEPARATION AND PURIFICATION TECHNOLOGY
·
2018
·
IF 3.927
Yuefei Zhang,Haibing Wang,Ningjie Sun,Ruan Chi
The mechanism of adsorption of dichromate by imidazole ionic liquid-bonded silica gel was studied. Two different adsorbents for adsorption of dichromate ions were synthesized and characterized. By static adsorption experiments, when the pH was 5.6 and the initial concentration of Cr was 200 μg/mL, the adsorption capacity of 1-methylimidazole ionic liquid-bonded silica gel (SilprMmimCl) and 1-ethylimidazole ionic liquid-bonded silica gel (SilprEmimCl) for Cr (VI) was 24.03 mg/g and 16.52 mg/g, respectively. To investigate the mechanism of adsorption on molecular scale, an simplified model of SilprMmimCl and SilprEmimCl have been modeled with [Mmim]Cl, [Emim]Cl, [Mmim][Cr 2 O 7 ] and [Emim][Cr 2 O 7 ]. The structures of related models were optimized at the B3LYP/6-311+G(d, p) level. The weak interaction between cations and anions of models was analyzed by vibration analysis and bond length analysis; the features of bonds at bond critical points and the variations of bond types was studied by Atoms In Molecules (AIM) theory. Simultaneously, noncovalent interactions were characterized and visualized by analysis of Reduced Density Gradient (RDG). Finally, The sequence of intra-molecular interaction energy is [Mmim][Cr 2 O 7 ], [Emim][Cr 2 O 7 ], [Mmim]Cl, [Emim]Cl from big to small, which demonstrates why SilprMmimCl and SilprEmimCl have a good adsorption capacity for dichromate and the adsorption capacity of SilprMmimCl is slightly more than that of SilprEmimCl.
研究领域:
环境科学
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计算化学
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材料科学
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DOI
高影响因子
Journal of Cleaner Production
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2023
·
IF 11.1
Xinqian Li,Bo Li,Yaping Dong,Zhengrong Niu,Dandan Gao,Haitao Feng,Wu Li
How to effectively and environmentally purify chromate solutions containing impurities such as silicon and vanadium, and avoid the generation of Cr(VI)-containing residues are important issues to be solved urgently. Herein, a novel Cr 2 O 3 ∙2.7H 2 O adsorbent with stable three-dimensional nanoflower structure was fabricated using the hydrothermal method , which was successfully implemented in the removal of Si(IV) and V(V) from dichromate system. Batch adsorption experiments revealed that the saturated adsorption capacity of Si(IV) was 140.06 mg/g at pH 9 and 132.98 mg/g V(V) at pH 2. Furthermore, density functional theory (DFT) calculations revealed that V(V) anionic species exhibited high adsorption energies (−990.70 kJ/mol, −697.10 kJ/mol) and small adsorption distances from the β-CrOOH(012) (≈1.89 Å, 1.98 Å), verifying the selective adsorption of Cr 2 O 3 ∙2.7H 2 O on V(V) in Cr(VI)–Si(IV)–V(V) ternary systems . The integrated mechanisms of electrostatic interaction, coordination, polymerization and precipitation for the removal behaviors were proposed via FT-IR, XPS and DFT calculations. In the real Na 2 Cr 2 O 7 complex solutions, the simultaneous removal rates of 88.48% Si(IV) and 80% V(V) were achieved, with optimal adsorption conditions at a pH of 8 and a temperature of 333 K. Furthermore, the desorbed Cr 2 O 3 ∙2.7H 2 O can be effectively converted into high-value nano Cr 2 O 3 , indicating the potential of this new green adsorbent. Therefore, this study not only imparts theoretical and practical insights into the purification of chromate solutions but also contributes to the advancement of cleaner chromium compound production by facilitating the high-value conversion of the adsorbent.
研究领域:
环境科学
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材料科学
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化学工程
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DOI
高影响因子
Polymers
·
2025
·Vol. 17
·期 10
·1413
·
IF 4.9
Huimin Gao,Wei Mao,Pize Xiao,Chutong Ling,Zhiming Wu,Jinghong Zhou
5-Hydroxymethylfurfural (HMF) is a versatile carbohydrate-derived platform chemical that has been used for the synthesis of a number of commercially valuable compounds. In this study, several chromium (Cr)-doped, biomass-derived hydrochar catalysts were synthesized via the one-pot method using starch, eucalyptus wood, and bagasse as carbon sources. Then, the performance of these synthesized materials for the catalytic conversion of glucose into HMF was evaluated by, primarily, the yield of HMF. The synergistic interactions between the Cr salt and the different biomass components were investigated, along with their effects on the catalytic efficiency. The differences in the catalytic activity of the synthesized materials were analyzed through structural characterization, as well as assessments of the acid density and strength. Among the catalysts, Cr5BHC180derived from bagasse presented the highest activity, achieving an HMF yield of 64.5% in an aqueous solvent system of dimethyl sulfoxide (DMSO) and saturated sodium chloride (NaCl) at 170 °C after 5 h. After four cycles, the HMF yield of Cr5BHC180decreased to 38.7%. Characterization techniques such as N2adsorption–desorption and Py-FTIR suggested that such a decline in the HMF yield is due to pore blockage and acid site coverage by humic by-products, as demonstrated by the fact that regeneration by calcination at 300 °C restored the HMF yield to 50.5%.
研究领域:
化学工程
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材料科学
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环境科学
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产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
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2022
·
IF 5.532
Guihong Han,Zhixiao Wang,Bingbing Liu,Yanfang Huang,Shengpeng Su
Existing refractory-life-extending technologies had concentrated on the preparation of homogeneous high-performance refractory materials in advance. In this paper, an in situ anti-erosion approach of conventional corundum-mullite refractory material was proposed for the incineration of hazardous spent high-salt organic liquor, in which the powdery additives were directly added into the spent liquor. The phase transformation, interfacial morphology evolution, and pore distribution of the corundum-mullite refractory with and without Cr 2 O 3 /ZrO 2 addition were compared, and the in situ anti-erosion mechanism was determined via the XRD , SEM, XPS , mercury intrusion porosimetry , and thermodynamic analyses. In conventional corrosion, molten Na 2 SO 4 , the primary phase of incinerating slag, directly entered the interior of the corundum-mullite refractory through pores on the interface. The Na 2 SO 4 strongly reacted with alumina and silica at 1000–1300 °C to produce liquid albite and nepheline. Upon the addition of Cr 2 O 3 into the spent liquor, the Cr 2 O 3 powder was suspended in the spent liquor and deposited at the refractory interface to form a protective (Al,Cr) 2 O 3 solid solution layer with Al 2 O 3 . The dense corrosion-resistant layer of (Al,Cr) 2 O 3 with a depth of 0–3 mm on the surface of the firebricks seldom reacted with molten Na 2 SO 4 . This protective layer can effectively slow down the penetration and erosion of incinerating slag. The environmental risks of Cr(VI) contamination associated with the Cr 2 O 3 addition in the incineration process were also evaluated in this work. Eventually, preliminary trial operation results showed that the service life of the corundum-mullite firebrick was prolonged after 5% Cr 2 O 3 addition into the spent liquor.
研究领域:
材料科学
·
腐蚀与防护
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DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2018
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IF 4.61
Wuhui Luo,Jiping Ouyang,Philip Antwi,Meng Wu,Zhiqiang Huang,Weiwei Qin
Butane-1,4-bis(dodecyl dimethyl ammonium bromide) (gBDDA) and dodecyl trimethyl ammonium bromide (DTMA) in same stoichiometric amounts were applied to modify montmorillonite (Mt) under microwave and ultrasound conditions. The composition and structure of products were obtained through multiple characterizations including XRD, FTIR , TG/DTG, SEM, TEM , and N 2 adsorption/desorption measurements, and the adsorption performance of chromate and phenol on these products were also investigated. Intercalations of gBDDA and DTMA into interlayer space of Mt were observed, but the amount of anchored modifier on the external surface was larger for gBDDA compared with DTMA when the stoichiometric amount of modifier larger than 1.0 times cation exchange capacity of Mt was added. Although there was no significant difference in morphology among products, the interlayer space distance, specific surface area, and pore size distribution were closely associated with the species and amount of applied modifier. Adsorption of phenol on products through partition mechanism relied on not only organic content, but also the configuration of modifier. Meanwhile, adsorption of chromate mainly depended on the presence of counter ion (bromide), which accounted for the high adsorption capacity and initial adsorption rate on gOMt-0.75. The fitting parameters of adsorption results using pseudo-second order model and Freundlich model suggested that gBDDA-modified Mt could sequester phenol or chromate in the faster manner with higher affinity. Compared with the conventional surfactant such as DTMA, the study revealed that, using gemini surfactant such as gBDDA to modify Mt would significantly reduce or even has the potential to eradicate the secondary pollution by modifier release during adsorption process. This study provides a new direction for Mt modification intended to be used as adsorbents to treat polluted water with high standards such as drinking water .
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2018
·Vol. 18
·期 6
·4006-4013
·
IF 1.354
Peng Yinjie,Tang Donglin,Wang Qiao,He Ting,Chu Yineng,Li Ruihai
In this paper, multiwall carbon nanotubes (MWCNTs) were modified by Polyethylenimine of different molecular weight of 1800 (MWCNTs-18) and 7000 (MWCNTs-70). The structure and morphology of the functionalized MWCNTs were characterized by thermogravimetric analysis (TGA), X-ray powder
diffraction (XRD) and scanning electron microscopy (SEM). The curve of TGA showed that the mass loss of MWCNTs-18 and MWCNTs-70 were 46.5% and 51.9% respectively, which was remarkably different with pristine MWCNTs. The XRD demonstrated that the structure of the pristine MWCNTs and functionalized
MWCNTs were similar. In addition, the experiment of the removal of chromate from water solution using functionalized MWCNTs was also conducted. The experimental conditions such as concentration of chromate, temperature, pH were studied. The maximum uptake capacities for chromate anions were
obtained at the concentration of 0.4 mmol·L−1. The solution pH showed a significant effect on chromate removal over a pH range from 4.0 to 9.0. Besides, the uptake capacities for chromate anions on MWCNTs-18 and MWCNTs-70 increased as the temperature increase within
the range from 30 to 60 °C. Under the experimental conditions, the maximum uptake capacities of MWCNTs-18 and MWCNTs-70 for chromate anions were 0.27 and 0.33 mmol·g−1 respectively. The thermodynamic parameters of the uptake process were calculated, and the results
showed that the process of uptake chromate was spontaneous.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
National Science Review
·
2019
·Vol. 7
·期 3
·652-659
·
IF 13.222
Chen Xianjie,Xu Yuan,Ma Xinguo,Zhu Yongfa
Herein, a wide-spectrum (∼678 nm) responsive Bi8(CrO4)O11 photocatalyst with a theoretical solar spectrum efficiency of 42.0% was successfully constructed. Bi8(CrO4)O11 showed highly efficient and stable photocatalytic water oxidation activity with a notable apparent quantum efficiency of 2.87% (420 nm), superior to many reported wide-spectrum driven photocatalysts. Most remarkably, its strong oxidation ability also enables the simultaneous degradation and complete mineralization for phenol, and its excellent performance is about 23.0 and 2.9 times higher than CdS and P25-TiO2, respectively. Its high activity is ascribed to the giant internal electric field induced by its large crystal dipole, which accelerates the rapid separation of photogenerated electron–hole pairs. Briefly, the discovery of wide-spectrum bismuth chromate and the mechanism of exponentially enhanced photocatalytic performance by increasing the crystal dipole throw light on improving solar energy conversion.
研究领域:
材料科学
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环境科学
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化学
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DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2018
·Vol. 101
·期 11
·4880-4886
·
IF 2.956
Dan Liu,Peng Shi,Wei Ren,Yantao Liu,Ming Liu,Gang Niu,Qijing Lin,Bian Tian,Zhuangde Jiang,Zuo-Guang Ye
Film thermocouples as the most effective tool are used to monitor the real-time and accurate in situ temperature in harsh environment, which will demand their electrodes with high thermal-resistant properties, high sensitivity, and stability. In this work, a series of solid solutions based on strontium lanthanum chromate were systematically investigated as new electrodes. LaCrO 3 and La 0.8 Sr 0.2 CrO 3 with some glass additives were chosen to fabricate high-performance thick-film thermocouple due to a bigger Fermi level difference between them. The thermocouple shows a high sensitivity (107.8 μV/°C) during static calibration, and an excellent reproducibility and stability during multicycle calibrations carried out up to 1550°C, resulting in a record ultra-high temperature sensing in film thermocouples. This facile thermocouple may open up a new way to measure high temperature in air or oxidation atmosphere accurately.
研究领域:
材料科学
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传感器技术
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DOI
高影响因子
ACTA PHYSICO-CHIMICA SINICA
·
2023
·
IF 10.9
Chengbo Zhang,Xiaoping Tao,Wenchao Jiang,Junxue Guo,Pengfei Zhang,Can Li,Rengui Li
The conversion of renewable solar energy into chemical energy is an important topic in research. Recently, bismuth chromate (Bi 2 CrO 6 ) has attracted attention in photocatalytic research, particularly for its potential applications in pollutant degradation and water splitting. This layered metal oxide exhibits a narrow optical band gap of approximately 1.9 eV and can utilize most of visible light in the solar spectrum. However, the photocatalytic activity of Bi 2 CrO 6 is relatively low, and its poor charge separation properties restrict its practical applications. Herein, we report a microwave-assisted hydrothermal method for the fabrication of Bi 2 CrO 6 crystals with high crystallinity and uniform morphology. Compared with the conventional preparations, microwave irradiation induces rapid volumetric heating and greatly accelerates nucleation and growth reactions, forming Bi 2 CrO 6 crystals within minutes. Multiple characterization methods, including X-ray diffraction, Raman scattering, and scanning electron microscopy, were employed to examine the crystallinity and morphologies of the samples. Microwave-assisted synthesized Bi 2 CrO 6 crystals showed better water oxidation activity in photocatalytic and photoelectrochemical tests than the conventional samples. Oxygen evolution rates were boosted 7.2 and 3.1 times using AgNO 3 and Fe(NO 3 ) 3 as electron acceptors, respectively. Further investigations showed that microwave-assisted Bi 2 CrO 6 crystals exhibited improved photogenerated charge separation. The average lifetime of photogenerated carriers, calculated from time-resolved photoluminescence results, also showed an increase. Furthermore, using photodeposition of metals and oxides as probes, the spatial separation of photogenerated electrons and holes was demonstrated to take place between {001} top and side facets of the Bi 2 CrO 6 crystal samples. Loading reduction and oxidation cocatalysts onto different facets significantly enhanced the photocatalytic activities. These results enforce the promise of microwave-assisted Bi 2 CrO 6 crystal synthesis for photocatalytic water-splitting applications and present a solution for efficient solar-energy conversion. Download: Download high-res image (64KB) Download: Download full-size image
研究领域:
材料科学
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化学
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能源科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）