X-ray Raman scattering provides evidence for interfacial acetonitrile-water dipole interactions in aqueous solutions

We explore the influence of the two osmolytes ectoine and hydroxyectoine on the structure of pure water and aqueous NaCl solutions using non-resonant X-ray Raman scattering spectroscopy at the oxygen K-edge.

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Hydration in aqueous osmolyte solutions: the case of TMAO and urea

Physical Chemistry Chemical Physics ◽

10.1039/c9cp06785j ◽

2020 ◽

Vol 22 (20) ◽

pp. 11614-11624 ◽

Cited By ~ 2

Author(s):

Christoph J. Sahle ◽

Martin A. Schroer ◽

Johannes Niskanen ◽

Mirko Elbers ◽

Cy M. Jeffries ◽

...

Keyword(s):

Hydrogen Bond ◽

Raman Scattering ◽

Aqueous Solutions ◽

First Principles ◽

Raman Scattering Spectroscopy ◽

X Ray ◽

Bond Topology

X-ray Raman scattering spectroscopy and first principles simulations reveal details of the hydration and hydrogen-bond topology of trimethylamine N-oxide (TMAO) and urea in aqueous solutions.

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Aggregate structures of asymmetric di-alkylphosphate anions in concentrated aqueous solutions and the role of the short chain: X-ray diffraction and Raman scattering studies

Colloid & Polymer Science ◽

10.1007/s00396-013-2925-x ◽

2013 ◽

Vol 291 (8) ◽

pp. 1927-1932 ◽

Cited By ~ 1

Author(s):

S. Sasuga-Araki ◽

K. Suzuki ◽

H. Okabayashi ◽

C. J. O’Connor

Keyword(s):

Raman Scattering ◽

Aqueous Solutions ◽

Short Chain ◽

X Ray Diffraction ◽

Concentrated Aqueous Solutions ◽

X Ray ◽

Aggregate Structures

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NEAR EDGE FINE STRUCTURE OF Li, Be AND GRAPHITE BY X-RAY RAMAN SCATTERING

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19879155 ◽

1987 ◽

Vol 48 (C9) ◽

pp. C9-863-C9-866 ◽

Cited By ~ 1

Author(s):

H. NAGASAWA

Keyword(s):

Fine Structure ◽

Raman Scattering ◽

X Ray

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Preparation and Characterization of the Sulfur-Impregnated Natural Zeolite Clinoptilolite for Hg(II) Removal from Aqueous Solutions

Processes ◽

10.3390/pr9020217 ◽

2021 ◽

Vol 9 (2) ◽

pp. 217

Author(s):

Marin Ugrina ◽

Martin Gaberšek ◽

Aleksandra Daković ◽

Ivona Nuić

Keyword(s):

Chemical Modification ◽

Aqueous Solutions ◽

Specific Surface ◽

Surface Area ◽

Natural Zeolite ◽

Contact Time ◽

Liquid Ratio ◽

X Ray ◽

Solid Liquid

Sulfur-impregnated zeolite has been obtained from the natural zeolite clinoptilolite by chemical modification with Na2S at 150 °C. The purpose of zeolite impregnation was to enhance the sorption of Hg(II) from aqueous solutions. Chemical analysis, acid and basic properties determined by Bohem’s method, chemical behavior at different pHo values, zeta potential, cation-exchange capacity (CEC), specific surface area, X-ray powder diffraction (XRPD), scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), as well as thermogravimetry with derivative thermogravimetry (TG-DTG) were used for detailed comparative mineralogical and physico-chemical characterization of natural and sulfur-impregnated zeolites. Results revealed that the surface of the natural zeolite was successfully impregnated with sulfur species in the form of FeS and CaS. Chemical modification caused an increase in basicity and the net negative surface charge due to an increase in oxygen-containing functional groups as well as a decrease in specific surface area and crystallinity due to the formation of sulfur-containing clusters at the zeolite surface. The sorption of Hg(II) species onto the sulfur-impregnated zeolite was affected by the pH, solid/liquid ratio, initial Hg(II) concentration, and contact time. The optimal sorption conditions were determined as pH 2, a solid/liquid ratio of 10 g/L, and a contact time of 800 min. The maximum obtained sorption capacity of the sulfur-impregnated zeolite toward Hg(II) was 1.02 mmol/g. The sorption mechanism of Hg(II) onto the sulfur-impregnated zeolite involves electrostatic attraction, ion exchange, and surface complexation, accompanied by co-precipitation of Hg(II) in the form of HgS. It was found that sulfur-impregnation enhanced the sorption of Hg(II) by 3.6 times compared to the natural zeolite. The leaching test indicated the retention of Hg(II) in the zeolite structure over a wide pH range, making this sulfur-impregnated sorbent a promising material for the remediation of a mercury-polluted environment.

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Collapse of vibrational structure in spectra of resonant x-ray Raman scattering

Physical Review A ◽

10.1103/physreva.56.256 ◽

1997 ◽

Vol 56 (1) ◽

pp. 256-264 ◽

Cited By ~ 57

Author(s):

Faris Gel’mukhanov ◽

Timofei Privalov ◽

Hans Ågren

Keyword(s):

Raman Scattering ◽

Vibrational Structure ◽

X Ray

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Magnetically Recyclable Wool Keratin Modified Magnetite Powders for Efficient Removal of Cu2+ Ions from Aqueous Solutions

Nanomaterials ◽

10.3390/nano11051068 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1068

Author(s):

Xinyue Zhang ◽

Yani Guo ◽

Wenjun Li ◽

Jinyuan Zhang ◽

Hailiang Wu ◽

...

Keyword(s):

Electron Microscopy ◽

Aqueous Solutions ◽

Adsorption Capacity ◽

Surface Area ◽

Ion Concentration ◽

Bet Surface Area ◽

Chemical Compositions ◽

Ion Adsorption ◽

X Ray ◽

Wool Keratin

The treatment of wastewater containing heavy metals and the utilization of wool waste are very important for the sustainable development of textile mills. In this study, the wool keratin modified magnetite (Fe3O4) powders were fabricated by using wool waste via a co-precipitation technique for removal of Cu2+ ions from aqueous solutions. The morphology, chemical compositions, crystal structure, microstructure, magnetism properties, organic content, and specific surface area of as-fabricated powders were systematically characterized by various techniques including field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), thermogravimetric (TG) analysis, and Brunauer–Emmett–Teller (BET) surface area analyzer. The effects of experimental parameters such as the volume of wool keratin hydrolysate, the dosage of powder, the initial Cu2+ ion concentration, and the pH value of solution on the adsorption capacity of Cu2+ ions by the powders were examined. The experimental results indicated that the Cu2+ ion adsorption performance of the wool keratin modified Fe3O4 powders exhibited much better than that of the chitosan modified ones with a maximum Cu2+ adsorption capacity of 27.4 mg/g under favorable conditions (0.05 g powders; 50 mL of 40 mg/L CuSO4; pH 5; temperature 293 K). The high adsorption capacity towards Cu2+ ions on the wool keratin modified Fe3O4 powders was primarily because of the strong surface complexation of –COOH and –NH2 functional groups of wool keratins with Cu2+ ions. The Cu2+ ion adsorption process on the wool keratin modified Fe3O4 powders followed the Temkin adsorption isotherm model and the intraparticle diffusion and pseudo-second-order adsorption kinetic models. After Cu2+ ion removal, the wool keratin modified Fe3O4 powders were easily separated using a magnet from aqueous solution and efficiently regenerated using 0.5 M ethylene diamine tetraacetic acid (EDTA)-H2SO4 eluting. The wool keratin modified Fe3O4 powders possessed good regenerative performance after five cycles. This study provided a feasible way to utilize waste wool textiles for preparing magnetic biomass-based adsorbents for the removal of heavy metal ions from aqueous solutions.

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Electronic Structures of Crystalline and Aqueous Solutions of LiBr, NaBr, KBr, and KBrO3: In Situ Br L-Edge Near-edge X-ray Absorption Fine Structure

The Journal of Physical Chemistry B ◽

10.1021/jp0304327 ◽

2003 ◽

Vol 107 (46) ◽

pp. 12562-12565 ◽

Cited By ~ 5

Author(s):

Shuji Matsuo ◽

Ponnusamy Nachimuthu ◽

Dennis W. Lindle ◽

Hisanobu Wakita ◽

Rupert C. C. Perera

Keyword(s):

Fine Structure ◽

Aqueous Solutions ◽

Electronic Structures ◽

X Ray ◽

Absorption Fine ◽

X Ray Absorption

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Fabrication of Carboxymethylcellulose/Metal-Organic Framework Beads for Removal of Pb(II) from Aqueous Solution

Materials ◽

10.3390/ma12060942 ◽

2019 ◽

Vol 12 (6) ◽

pp. 942 ◽

Cited By ~ 10

Author(s):

Huo-Xi Jin ◽

Hong Xu ◽

Nan Wang ◽

Li-Ye Yang ◽

Yang-Guang Wang ◽

...

Keyword(s):

Aqueous Solutions ◽

Adsorption Capacity ◽

Photoelectron Spectroscopy ◽

Langmuir Isotherm ◽

Adsorption Equilibrium ◽

Isotherm Model ◽

Maximum Adsorption Capacity ◽

X Ray ◽

Metal Organic ◽

Langmuir Isotherm Model

The ability to remove toxic heavy metals, such as Pb(II), from the environment is an important objective from both human-health and ecological perspectives. Herein, we describe the fabrication of a novel carboxymethylcellulose-coated metal organic material (MOF-5–CMC) adsorbent that removed lead ions from aqueous solutions. The adsorption material was characterized by Fourier-transform infrared spectroscopy, X-ray diffractometry, scanning electron microscopy, and X-ray photoelectron spectroscopy. We studied the functions of the contact time, pH, the original concentration of the Pb(II) solution, and adsorption temperature on adsorption capacity. MOF-5–CMC beads exhibit good adsorption performance; the maximum adsorption capacity obtained from the Langmuir isotherm-model is 322.58 mg/g, and the adsorption equilibrium was reached in 120 min at a concentration of 300 mg/L. The adsorption kinetics is well described by pseudo-second-order kinetics, and the adsorption equilibrium data are well fitted to the Langmuir isotherm model (R2 = 0.988). Thermodynamics experiments indicate that the adsorption process is both spontaneous and endothermic. In addition, the adsorbent is reusable. We conclude that MOF-5–CMC is a good adsorbent that can be used to remove Pb(II) from aqueous solutions.

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Effectiveness of Calcium Deficiency in Nanosized Hydroxyapatite for Removal of Fe(II), Cu(II), Ni(II) and Cr(VI) Ions from Aqueous Solutions

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.56.17 ◽

2019 ◽

Vol 56 ◽

pp. 17-27

Author(s):

Van Dat Doan ◽

Van Thuan Le ◽

Hoang Sinh Le ◽

Dinh Hien Ta ◽

Hoai Thuong Nguyen

Keyword(s):

Electron Microscopy ◽

Ion Exchange ◽

Aqueous Solutions ◽

Calcium Deficiency ◽

Exchange Mechanism ◽

Precipitation Method ◽

X Ray ◽

Transmission Electron ◽

Bet Method ◽

Langmuir Isotherm Model

In this work, nanosized calcium deficient hydroxyapatite (nCDHA) was synthesized by the precipitation method, and then utilized as an adsorbent for removal of Fe (II), Cu (II), Ni (II) and Cr (VI) ions from aqueous solutions after characterizing it by various techniques as scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX) and BET method. A possible structure of synthesized nCDHA was proposed. The adsorption study indicated that the adsorption equilibrium is well fitted with Langmuir isotherm model with the maximum adsorption capacities followed the order of Fe (II) > Cu (II) > Ni (II) > Cr (VI) with the values of 137.23, 128.02, 83.19 and 2.92 mg/g, respectively. The ion-exchange mechanism was dominant for the adsorption of metal ions onto nCDHA at initial metal concentrations lower than 0.01 mol/L. Along with the ion-exchange mechanism, there was an additional precipitation occurred on the surface of nCDHA in the case of Fe (II) and Cu (II) at initial concentrations higher than 0.01 mol/L.

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