Characterization of a new Ca–Cd hydroxide hydrothermally synthesized and its implications for cement isolation of Cd

1998 ◽  
Vol 13 (1) ◽  
pp. 16-21 ◽  
Author(s):  
S. Gñni ◽  
A. Macías ◽  
J. Madrid ◽  
J. M. Díez
Keyword(s):  
Infrared Spectroscopy ◽  
Pore Solution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Predominant Species ◽  
Solubility Constant ◽  
Tg And Dtg ◽  
Low Solubility ◽  
Mechanism Of The Reaction

Mixtures of CaO–CdO (1 : 1) were hydrothermally treated in a pressure reactor at 200 °C and 200 psi of pressure during a period of 16 h. The evolution of the reaction was followed by x-ray diffraction (XRD), infrared spectroscopy (IR), and thermogravimetric (TG and DTG) analysis. Also, the composition of the filtered solutions was analyzed to determine the mechanism of the reaction as well as the thermodynamic solubility constant of the new compound formed. The results show that CaO and CdO react, giving rise to a new CaCd(OH)4 hydroxide whose thermodynamic solubility constant, 1.5 ± 0.4 × 10−11 M2, is six orders of magnitude lower than those of both Ca(OH) 2 and β–Cd(OH) 2. This low solubility constant justifies the Cd2+ concentration measured in the pore solution of cement matrices used to immobilize cadmium containing wastes. The mechanism of the reaction proposed is via dissolution of both Ca(OH) 2 and β–Cd(OH)2, Ca2+ and being the predominant species in solution.

Stability of sodalite relative to nepheline in NaCl–H2O brines at 750 °C: Implications for hydrothermal formation of sodalite

2020 ◽  
Vol 58 (1) ◽  
pp. 3-18 ◽  
Author(s):  
Jonathan B. Schneider ◽  
David M. Jenkins
Keyword(s):  
Infrared Spectroscopy ◽  
Constant Temperature ◽  
Molar Ratio ◽  
Standard State ◽  
X Ray Diffraction ◽  
Cage Structure ◽  
X Ray ◽  
Brine Concentration

ABSTRACT Formation of the feldspathoid sodalite (Na6Al6Si6O24·2NaCl) by reaction of nepheline (NaAlSiO4) with NaCl-bearing brines was investigated at 3 and 6 kbar and at a constant temperature of 750 °C to determine the brine concentration at which sodalite forms with variation in pressure. The reaction boundary was located by reaction-reversal experiments in the system NaAlSiO4–NaCl–H2O at a brine concentration of 0.16 ± 0.08 XNaCl [= molar ratio NaCl/(NaCl + H2O)] at 3 kbar and at a brine concentration of 0.35 ± 0.03 XNaCl at 6 kbar. Characterization of the sodalite using both X-ray diffraction and infrared spectroscopy after treatment in these brines indicated no obvious evidence of water or hydroxyl incorporation into the cage structure of sodalite. The data from this study were combined with earlier results by Wellman (1970) and Sharp et al. (1989) at lower (1–1.5 kbar) and higher (7–8 kbar) pressures, respectively, on sodalite formation from nepheline and NaCl which models as a concave-down curve in XNaCl – P space. In general, sodalite buffers the concentration of neutral aqueous NaCl° in the brine to relatively low values at P < 4 kbar, but NaCl° increases rapidly at higher pressures. Thermochemical modeling of these data was done to determine the activity of the aqueous NaCl° relative to a 1 molal (m) standard state, demonstrating very low activities (<0.2 m, or 1.2 wt.%) of NaCl° at 3 kbar and lower, but rising to relatively high activities (>20 m, or 54 wt.%) of NaCl° at 6 kbar or higher. The results from this study place constraints on the concentration of NaCl° in brines coexisting with nepheline and sodalite and, because of the relative insensitivity of this reaction to temperature, can provide a convenient geobarometer for those localities where the fluid compositions that formed nepheline and sodalite can be determined independently.

Preparation and characterization of poly(tetramethyl-p-phenylenediamine)/clay hybrids via intercalative polymerization

2003 ◽  
Vol 18 (2) ◽  
pp. 482-486 ◽  
Author(s):  
Guangming Chen ◽  
Nobuo Iyi ◽  
Taketoshi Fujita
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Thermal Behavior ◽  
Fourier Transform Infrared Spectroscopy ◽  
Interlayer Space ◽  
X Ray Diffraction ◽  
X Ray ◽  
Noncovalent Bonding ◽  
Intercalative Polymerization

New noncovalent bonding polymer/clay hybrids were prepared, including the polymer poly(tetramethyl-p-phenylenediamine) (poly-TMPD). Polymerization occurred in the interlayer space of clay mineral successively after intercalation of monomers. Two types of clay minerals with different surface properties—a hydrophilic lithium fluorotaeniolite (TN) and four kinds of organophilic fluorotaeniolites (org-TNs)—were used as the hosts. Powder x-ray diffraction results showed an increase of 0.7–1.0 nm in the basal spacings, indicating the formation of poly–TMPD in the interlayer space of the hosts. Intercalative polymerization was also supported by Fourier transform infrared spectroscopy. The orientation of the poly-TMPD and thermal behavior were also discussed.

Characterization of Three 'Active' Rhodium(III) Hydroxides

1995 ◽  
Vol 48 (3) ◽  
pp. 557 ◽  
Author(s):  
SJ Crimp ◽  
L Spiccia
Keyword(s):  
Thermal Analysis ◽  
Thermal Decomposition ◽  
Infrared Spectroscopy ◽  
Ion Exchange ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
X Ray Diffraction ◽  
X Ray

Pure solutions of [ Rh (H2O)6]3+, dimer [Rh2(μ-OH)2(H2O)8]4+ and trimer [Rh3(μ-OH)4(H2O)10]5+ have been converted into their respective 'active' hydroxides by dropwise addition to an imidazole solution. These 'active' hydroxides have been analysed by a variety of techniques including rhodium determination, infrared spectroscopy, thermal analysis and powder X-ray diffraction. Purity determinations using ion-exchange chromatography showed that the three hydroxides consist primarily of the neutral forms of the starting aqua ion (>96%) with small amounts of species with higher nuclearity. Rhodium analysis and thermogravimetric measurements confirmed the composition of these hydroxides to be Rh (OH)3(H2O)3.H2O, Rh2(μ-OH)2(OH)4(H2O)4 and Rh3(μ-OH)4(OH)5(H2O)5.5H2O. A scheme for the thermal decomposition of each of the hydroxides has been proposed on the basis of the t.g . and d.t.a . data and the knowledge that the final product in each case is α-Rh2O3. Heating of the hydroxides in air resulted in oxidation of RhIII to RhIV (temperature 250-300°C) forming RhO2 which on further heating decomposed to α-Rh2O3 and dioxygen.

Synthesis and Structural Characterization of a Series of Group 11 2,2-Dialkyl-1,3-dicyclohexylguanidinate Complexes

2014 ◽  
Vol 67 (7) ◽  
pp. 1021 ◽  
Author(s):  
Sonya K. Adas ◽  
Jesus A. Ocana ◽  
Scott D. Bunge
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
X Ray Diffraction ◽  
Nmr Studies ◽  
X Ray ◽  
7Li Nmr ◽  
Elemental Analyses ◽  
Lithium Diethylamide ◽  
Structural Aspects

The addition of either lithium dimethylamide or lithium diethylamide to a tetrahydrofuran (THF) solution of 1,3-dicyclohexylcarbodiimide yielded THF adducts of lithium 2,2-dimethyl-1,3-dicyclohexylguandidinate (1) and lithium 2,2-diethyl-1,3-dicyclohexylguandidinate (2), respectively. One equivalent of either 1 or 2 was subsequently reacted with one equivalent of Group 11 halide (CuCl, AgBr, and AuCl) to generate oligonuclear complexes with the general formula {M[CyNC(NR2)NCy]}n where M, R, and n are respectively Cu, CH3, 2 (3); Cu, CH2CH3, 2 (4); Ag, CH3, 3 (5); Ag, CH2CH3, 3 (6); Au, CH3, 2 (7); and Au, CH2CH3, 2 (8). Compounds 1–8 were characterized by single-crystal X-ray diffraction. The bulk powders for all complexes were found to be in agreement with the crystal structures based on elemental analyses, Fourier transform infrared spectroscopy, and 1H, 13C, and 7Li NMR studies. The unique structural aspects of this family of Group 11 complexes are highlighted.

Preparation and Preliminary Characterization of Chitosan from Catharsius molossus Discards

2012 ◽  
Vol 548 ◽  
pp. 77-81
Author(s):  
Jia Hua Ma ◽  
Cheng Jia Tan ◽  
Xia Deng ◽  
Chao Xin
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Oxalic Acid ◽  
Room Temperature ◽  
Orthogonal Design ◽  
X Ray Diffraction ◽  
X Ray ◽  
Preparation Techniques ◽  
Better Than

Preparation techniques of chitosan from Catharsius molossus L. processing discards were studied by orthogonal design. Preparation techniques were as follows:demineralizing: soaked for 30 min at 80 °C with 1.3 mol•L-1 HCl, then kept for 12 h under room temperature. Deproteinization and delipidation: treated for 6 h at 90 °C with 4 mol•L-1 NaOH. Decolorizing: soaked at room temperature with 3% KMnO4, then treated with 2% oxalic acid at 70 °C. Deacetylation: treated for 6 h at 110 °Cwith 14 mol•L-1 NaOH. Properties of chitosan were characterized by Fourier transform infrared spectroscopy(FTIR), X-ray diffraction (XRD), etc. It proved the technique was stable and feasible. The result also preliminarily showed that chitosan from Catharsius molossus L. was better than shrimp’s. It will be widely applicated in biomedical and other industrial areas with such exiciting properties.

Synthesis and Characterization of Copper(II) Complexes with Long Chain Dithiocarbamates

2014 ◽  
Vol 976 ◽  
pp. 164-168 ◽  
Author(s):  
Nayely Torres-Gomez ◽  
Alfredo R. Vilchis-Nestor ◽  
Rosa Maria Gomez-Espinosa ◽  
Ivan Garcia-Orozco
Keyword(s):  
Infrared Spectroscopy ◽  
Copper Complexes ◽  
Nanocrystalline Structure ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Long Chain ◽  
Scanning Electron

Copper complexes of dithiocarbamates ligands were obtained from RNH2 (R = C6H13-, C12H25- y C18H37-) and an excess of CS2 in the presence of NaOH. Sodium hexyldithiocarbamate is not possible to isolate from solution but the other two were obtained and characterizedby infrared spectroscopy, UV-vis and powder X-ray diffraction. Copper complexes were obtained in situ from ligand solution as greenish powders. All the complexes were characterized by infrared spectroscopy, UV-vis, powder X-ray diffraction and Scanning Electron Microscopy. The complexes show an amorphous phase in the case of DCu12 and nanocrystalline structure for DCu18, as observed in XRD.

scholarly journals Penggunaan ZnO/zeolit sebagai katalis dalam degradasi tartrazin secara ozonolisis

2021 ◽  
Vol 12 (1) ◽  
pp. 53-64
Author(s):  
Zilfa Zilfa ◽  
Safni Safni ◽  
Febi Rahmi
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Electron Microscope ◽  
Natural Zeolite ◽  
Zeolite Catalyst ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zeolite Structure ◽  
Scanning Electron

An investigation on modification of natural zeolite with ZnO for the degradation of tartrazine. In this study, ZnO as a semiconductor is modified into a natural zeolite as support to form ZnO/zeolite that can increase the efficiency degradation of tartrazine. Further, the formed catalyst was added to tartrazine by determining the variation in ozonolysis time, the amount of addition of the catalyst, and the addition of a catalyst time. The results of degradation were determined by UV-Vis spectrophotometer at 424 nm. The result showed that the percentage of degradation obtained on each catalyst in the degradation. The resulted percent degradation of 20 ml of tartrazine at concentration of 15 mg/L using 20 mg ZnO/zeolite was 56.80%, while using 0.77 mg ZnO was 42.25%, and with the addition of 19.23 mg of Zeolite was 31.18%, all of that condition was proceeded by 40 minutes of ozonolysis. Thus, the result indicates that the ZnO/zeolite catalyst can increase percentages of tartrazine degradation by ozonolysis. It is known that the catalyst ZnO/zeolite is very effective in increasing the degradation of tartrazine. Analysis of tartrazine compounds using fourier-transform infrared spectroscopy (FTIR) after degradation changes in wavenumber indicates that there is a breaking of the bonds of tartrazine compounds. Characterization of ZnO/zeolite catalyst using FTIR, X-Ray diffraction (XRD) and scanning electron microscope (SEM), in each spectrum there was no shift, indicating that there is no change in ZnO/zeolite structure

scholarly journals Synthesis and Characterization of a New Aluminum-Doped Bismuth Subcarbonate

Crystals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 466
Author(s):  
Loisangela Álvarez ◽  
Blanca Rojas de Gascue ◽  
Rolando J. Tremont ◽  
Edgar Márquez ◽  
Euclides J. Velazco
Keyword(s):  
Infrared Spectroscopy ◽  
Photoelectron Spectroscopy ◽  
Energy Dispersive ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
Characterization Methods ◽  
X Ray ◽  
Fourier Transformed Infrared Spectroscopy ◽  
Anionic Part

A new compound, Bi2O2CO3:Al, was synthesized by the coprecipitation method. The characterization was done by X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), electronic scanning microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX). The characterization methods allowed to identify the Bi2O2CO3:Al compound, such as the Al-doped Bi2O2CO3 by XRD, the anionic part (CO32−) by FTIR, and the presence of aluminum in the compound by XPS and EDX. It was confirmed to have a nanostructure like a nanosheet and a microstructure that resembles a type sponge by SEM.

Synthesis and structural characterization of two copper(II) complexes with 3-(4-(1H-benzo[d]imidazol-1-yl)-4-methoxyphenyl)-1-phenylprop- 2-en-1-one ligands

2015 ◽  
Vol 70 (3) ◽  
pp. 165-169 ◽  
Author(s):  
Gao-Feng Wang
Keyword(s):  
Infrared Spectroscopy ◽  
Single Crystal ◽  
Structural Characterization ◽  
X Ray Diffraction ◽  
Distorted Octahedral Environment ◽  
X Ray ◽  
Octahedral Environment ◽  
Distorted Octahedral ◽  
Elemental Analyses

AbstractThe synthesis of two new copper(II) complexes with benzimidazole type ligands, Cu(tta)2(L1)2 (1) and Cu(tta)2(L1) (2) (where L1 is 3-(4-(1H-benzo[d]imidazol-1-yl)-4-methoxy phenyl)-1-phenylprop-2-en-1-one; tta is 2-thenoyltrifluoroacetonate), are reported. Their structures have been characterized by infrared spectroscopy, elemental analyses and single-crystal X-ray diffraction. The copper(II) ion of 1 is in a distorted octahedral environment, while that of 2 is in a distorted square-pyramidal environment. In both cases, the donor atoms are provided by oxygen atoms of the tta ligands and nitrogen atoms of the L1 ligands.

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