Synthesis of Nanosized Pseudoboehmite and γ-Al2O3 by Control Precipitation Method

2013 ◽  
Vol 684 ◽  
pp. 46-52 ◽  
Author(s):  
Zhou Qing Jiang ◽  
Hong Wen Ma ◽  
Jing Yang ◽  
Le Wang
Keyword(s):  
Aqueous Solution ◽  
Diffraction Analysis ◽  
Sodium Sulfate ◽  
Ageing Time ◽  
Precipitation Method ◽  
Al2o3 Nanoparticles ◽  
X Ray Diffraction ◽  
Reaction Conditions ◽  
X Ray

Nanosized pseudoboehmite particles were synthesized by the precipitation of sodium sulfate and ammonia in aqueous solution at 70°C. After calcinations, the pseudoboehmite could successfully transfer to γ-Al2O3 nanoparticles while retaining their previous morphology. The influence of the reaction conditions on formation of pseudoboehmite and γ-Al2O3 had been researched in detail. The X-ray diffraction analysis showed that nanosized crystalline pseudoboehmite was formed at pH 8-8.5 after ageing 2 hours. Utilization of surfactant(PEG1000) would produce finer nanoparticles with well-dispersion. With the ageing time or the surfactant amount increasing, the morphology of the resulting particles transformed from spherical to fibrous

Removal of Heavy Metals from Aqueous Solution by Hydroxyapatite/Chitosan Composite

2013 ◽  
Vol 789 ◽  
pp. 176-179 ◽  
Author(s):  
Eny Kusrini ◽  
Nofrijon Sofyan ◽  
Dwi Marta Nurjaya ◽  
Santoso Santoso ◽  
Dewi Tristantini
Keyword(s):  
Heavy Metals ◽  
Aqueous Solution ◽  
Metal Ions ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Removal Of Heavy Metals ◽  
Sem Micrograph ◽  
Pseudo Second Order ◽  
Chitosan Composite

Hydroxyapatite/chitosan (HApC) composite has been prepared by precipitation method and used for removal of heavy metals (Cr6+, Zn2+and Cd2+) from aqueous solution. The HAp and 3H7C composite with HAp:chitosan ratio of 3:7 (wt%) were characterized by Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy-energy dispersive X-ray spectroscopy. The SEM results showed that HAp is spherical-shaped and crystalline, while chitosan has a flat structure. SEM micrograph of 3H7C composite reveals crystalline of HAp uniformly spread over the surface of chitosan. The crystal structure of HAp is maintained in 3H7C composite. Chitosan affects the adsorption capacity of HAp for heavy metal ions; it binds the metal ions as well as HAp. The kinetic data was best described by the pseudo-second order. Surface adsorption and intraparticle diffusion take place in the mechanism of adsorption process. The binding of HAp powder with chitosan made the capability of composite to removal of Cr6+, Zn2+and Cd2+from aqueous solution effective. The order of removal efficiency (Cr6+> Cd2+> Zn2+) was observed.

scholarly journals Synthesis, characterization and structure of the Bis(methyl-cyclopentadienyl)vanadium(IV) carboxylates

2005 ◽  
Vol 3 (1) ◽  
pp. 157-168 ◽  
Author(s):  
Jaromír Vinklarek ◽  
Jan Honzíĉek ◽  
Ivana Císařová ◽  
Martin Pavliŝta ◽  
Jana Holubová
Keyword(s):  
Aqueous Solution ◽  
Single Crystal ◽  
Diffraction Analysis ◽  
Carboxylic Acids ◽  
X Ray Diffraction ◽  
Monocarboxylic Acids ◽  
X Ray ◽  
Different Types ◽  
Chelate Compounds ◽  
Parameter Values

AbstractThe 1,1’-dimethylvanadocene dichloride ((C5H4CH3)2VCl2) reacts in aqueous solution with various carboxylic acids giving two different types of complexes. The 1,1’-dimethylvanadocene complexes of monocarboxylic acids (C5H4CH3)2V(OOCR)2 (R=H,CCl3, CF3, C6H5) contain two monodentate carboxylic ligands, whereas oxalic and malonic acids act as chelate compounds of the formula (C5H4CH3)2V(OOC-A-COO) (A=−, CH2). The structure of the (C5H4CH3)2 V(OOCCF3)2 complex was determined by single crystal X-ray diffraction analysis. The isotropic and anisotropic EPR spectra of all the complexes prepared were recorded. The obtained EPR parameter values were found to be in agreement with proposed structures.

Effect of Electrolyte on Micro Arc Oxidation Coating of Al-2014 Alloy

2018 ◽  
Vol 1148 ◽  
pp. 159-164 ◽  
Author(s):  
M.P. Shankar ◽  
R. Sokkalingam ◽  
K. Sivaprasad ◽  
Veerappan Muthupandi
Keyword(s):  
Aqueous Solution ◽  
Diffraction Analysis ◽  
Aluminium Alloy ◽  
Process Parameters ◽  
Coating Thickness ◽  
X Ray Diffraction ◽  
X Ray ◽  
Porous Layers ◽  
Micro Arc Oxidation ◽  
Phosphate Electrolyte

Micro Arc Oxidation (MAO) coating was performed on Al-2014 aluminium alloy in aqueous solution of silicate, phosphate and hybrid electrolytic environments. The MAO thickness was measured around 5-15 μm, in which significant thickness of both dense and porous layers were identified. A combination of nanocrystalline α-Al2O3and Υ-Al2O3 was identified in the MAO coating using X-ray diffraction analysis. The thickness and morphology of the coating, which is analyzed using SEM are different for different MAO process parameters and it was found that the MAO coating prepared in phosphate electrolyte is giving a better coating with higher coating thickness, minor pore size and better adherence.

Solid products of the reaction of lanthanum(III) nitrate with potassium hexa(isothiocyanato)chromate(III) in an aqueous solution: X-ray diffraction analysis

2008 ◽  
Vol 53 (7) ◽  
pp. 1115-1120 ◽  
Author(s):  
E. V. Cherkasova ◽  
E. V. Peresypkina ◽  
A. V. Virovets ◽  
E. S. Tatarinova ◽  
T. G. Cherkasova
Keyword(s):  
Aqueous Solution ◽  
Diffraction Analysis ◽  
X Ray Diffraction ◽  
X Ray

Structure of iron (II) and cobalt (II) bromide complexes in aqueous solution by X-ray diffraction analysis

1984 ◽  
Vol 13 (7) ◽  
pp. 505-516 ◽  
Author(s):  
Mitsuyoshi Ichihashi ◽  
Hisanobu Wakita ◽  
Isao Masuda
Keyword(s):  
Aqueous Solution ◽  
Diffraction Analysis ◽  
X Ray Diffraction ◽  
X Ray

Effect of Ag+ and PO43− ratios on the microstructure and photocatalytic activity of Ag3PO4

2016 ◽  
Vol 09 (05) ◽  
pp. 1650063 ◽  
Author(s):  
Jiaqian Qin ◽  
Xinyu Zhang ◽  
Chengwu Yang ◽  
Aijun Song ◽  
Bing Zhang ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Photocatalytic Activity ◽  
Diffuse Reflectance ◽  
Photocatalytic Performance ◽  
Diffuse Reflectance Spectroscopy ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Visible ◽  
The Rich

In this work, the catalyst silver phosphate (Ag3PO[Formula: see text] with different initial ratios of Ag[Formula: see text] and PO[Formula: see text] in aqueous solution was synthesized by a simple precipitation method from AgNO3 and NH4H2PO4 which were used as the precursor. After that, the prepared samples were characterized by different techniques such as field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), UV-visible diffuse reflectance spectroscopy (UV-DRS) and decomposition evolution of rhodamine B (RhB) solution. The results indicate that the initial ratios of Ag[Formula: see text]/PO[Formula: see text] in aqueous solution can modify the morphology and also it can significantly affect the photocatalytic performance. During photocatalytic process, the rich Ag[Formula: see text] ion Ag3PO4 can form the surface plasmon resonance (SPR) of Ag nanoparticles, which inhibit the reduction of Ag3PO4 resulting in higher photocatalytic activity and stability.

X-Ray Diffraction Analysis of YSAG:Yb Ceramic Powders with Different Stoichiometry

2020 ◽  
Vol 310 ◽  
pp. 1-5
Author(s):  
Marina S. Nikova ◽  
Dmitry S. Vakalov ◽  
Vitaly A. Tarala ◽  
Irina S. Chikulina ◽  
Fedor F. Malyavin ◽  
...  
Keyword(s):  
Diffraction Analysis ◽  
Chemical Precipitation ◽  
Chemical Precipitation Method ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Ceramic Powders ◽  
Oxide Composition ◽  
X Ray ◽  
Garnet Phase

Synthesis of YSAG:Yb ceramic powders with different stoichiometry by chemical precipitation method was carried out. It has been established that scandium can replace both dodecahedral and octahedral positions of garnet. It is shown that scandium is embedded in those positions that become available to it when the YAG:Yb composition deviates from stoichiometric. Thus, scandium can compensate for the lack of one of the components of the oxide composition Y2O3, Yb2O3, and Al2O3 during the formation of the garnet phase.

scholarly journals Rehydration Driven Na-Activation of Bentonite—Evolution of the Clay Structure and Composition

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7622
Author(s):  
Krzysztof Bahranowski ◽  
Agnieszka Klimek ◽  
Adam Gaweł ◽  
Ewa M. Serwicka
Keyword(s):  
Aqueous Solution ◽  
Fourier Transform ◽  
Cation Exchange Capacity ◽  
Ageing Time ◽  
Xrd Analysis ◽  
Exchange Capacity ◽  
X Ray Diffraction ◽  
Amorphous Calcium Carbonate ◽  
X Ray ◽  
Compositional Evolution

A new method of Na-activation of raw bentonite, rich in Ca-montmorillonite, consisting of combined thermal treatment at 200 °C, followed by immediate impregnation with aqueous solution of Na2CO3 of concentration corresponding to 0.5, 1.0, 1.5, or 2.0 cation exchange capacity (CEC) of clay, was investigated. Structural and compositional evolution of the activated solids after 1, 2, 3, and 4 weeks of storage was monitored by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). XRD analysis indicated that within the investigated period of ageing transformation to Na-rich montmorillonite required Na2CO3 concentration of at least 1.0 CEC. FTIR spectra showed that, depending on the Na2CO3 concentration and ageing time, formation of Na-rich montmorillonite was accompanied by precipitation of poorly crystalline calcite, amorphous calcium carbonate, gaylussite (a double calcium-sodium carbonate), and portlandite (Ca(OH)2).

Role of Synthesis Parameters on Structural and Electrical Properties of M-Type Hexa-Ferrites

2012 ◽  
Vol 510-511 ◽  
pp. 201-205
Author(s):  
G. Asghar ◽  
S. Nasir ◽  
M.S. Awan ◽  
G.H. Tariq ◽  
M. Akram ◽  
...  
Keyword(s):  
Particle Size ◽  
Diffraction Analysis ◽  
Precipitation Method ◽  
Molar Ratio ◽  
Narrow Particle Size Distribution ◽  
X Ray Diffraction ◽  
Phase Purity ◽  
X Ray ◽  
Volume Rate ◽  
Synthesis Parameters

Phase purity, particle size and its distribution contributes a lot to the physical properties of M-type hexa-ferrites. These parameters are strongly influenced by the variation in synthesis parameters. In the present work, effect of synthesis parameters such as molar ratio (Fe/Sr) and volume rate of addition of precipitating agent on M-type hexa-ferrite (SrFe12O19) prepared by co-precipitation method have been investigated systematically. The molar ratio (Fe/Sr) in SrFe12O19was varied as 12, 11, 10, 09, and 08. X-ray diffraction analysis revealed that molar ratio does not affect the phase purity. X-ray diffraction analysis of the samples prepared with different volume rate of addition of precipitating agent indicated that phase purity and micro-structural properties of SrFe12O19are greatly influenced by the above synthesis parameter. High volume rate of addition of precipitating agent resulted in high phase purity, smaller particle size, and narrow particle size distribution.

Sign in / Sign up

Export Citation Format

Share Document