Processing and properties of high-purity micro-lamellate (NH4)2RuCl6 particles

2018 ◽  
Vol 7 (1) ◽  
pp. 16-22
Author(s):  
Zena Xin ◽  
Panchao Zhao ◽  
Jialin Chen ◽  
Yaohong Ma ◽  
Ying Xu ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
High Purity ◽  
Solid Phase ◽  
Decomposition Process ◽  
X Ray Diffraction ◽  
Thermal Decomposition Process ◽  
X Ray ◽  
Thermal Decomposition Behavior ◽  
Decomposition Behavior ◽  
Two Stages

Abstract(NH4)2RuCl6is an important precursor in the synthesis of Ru powder with high-purity requirement. In this study, high-purity (>99.999 wt%) micro-sized (NH4)2RuCl6pieces were synthesized by distillation and precipitation from crude Ru powder. Then, the thermal decomposition behavior of the (NH4)2RuCl6pieces was investigated. The decomposition process included two stages. First, (NH4)2RuCl6was decomposed from 255.0°C to 314.0°C, with the endothermic peak located at 309.4°C. At this stage, HCl and NH3were released, while the dense micro-pieces were transformed to loosened micro-pieces due to the thermal decomposition. Then, the solid phase [(NH3)4Ru3Cl12] kept decomposing from 314.0°C to 352.7°C, HCl and N2were released, and agglomerated Ru particles were achieved. Thermogravimetric analysis-differential thermal analysis-mass spectrum coupling (TG-DTA-MS) was used to monitor the thermal decomposition process and identify the released gaseous phases, respectively. The solid phases in different stages were characterized by high-temperature X-ray diffraction (HTXRD). A good understanding of the processing and thermal decomposition of (NH4)2RuCl6is crucial in the creation of Ru products.

Research on the Thermal Decomposition Process of K-Feldspar-CaSO4-CaO System

2013 ◽  
Vol 734-737 ◽  
pp. 916-920 ◽  
Author(s):  
Jing Xia Chao ◽  
Ju Pei Xia ◽  
Chao Qin Yang ◽  
Zhao Shu Zhang ◽  
Xue Jiao Ren
Keyword(s):  
Thermal Decomposition ◽  
Calcium Sulfate ◽  
Xrd Analysis ◽  
Operating Conditions ◽  
Decomposition Process ◽  
Complex Reaction ◽  
X Ray Diffraction ◽  
Thermal Decomposition Process ◽  
X Ray

The thermal decomposition process of K-feldspar-CaSO4-CaO system was studied by X-ray diffraction (XRD) analysis of the product which calcined at 1473K. The results show that KAlSi3O8 firstly is decomposed into KAlSi2O6 and released the SiO2, then has a complex reaction between KAlSi2O6 and CaO, which generated intermediates-K2SiO3 under the operating conditions. K2SiO3 is unstable and reacted with calcium sulfate to generate K2SO4. When the CaO amount is insufficient, the main products are KAlSi2O6 and 2CaOAl2O3SiO2, the potassium existed as K2S2O8; when n (CaO) / n (KAS6) 12:1, the products will further transfer into CaOSiO2 and 2CaO SiO2 and the potassium existed as K2SO4.

Probing the thermal decomposition process of layered double hydroxides through in situ 57Fe Mössbauer and in situ X-ray diffraction experiments

2006 ◽  
Vol 42 (2) ◽  
pp. 534-538 ◽  
Author(s):  
Daniel X. Gouveia ◽  
Odair P. Ferreira ◽  
Antonio G. Souza Filho ◽  
M. G. da Silva ◽  
J. A. C. de Paiva ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Layered Double Hydroxides ◽  
Decomposition Process ◽  
X Ray Diffraction ◽  
Thermal Decomposition Process ◽  
X Ray ◽  
57Fe Mössbauer ◽  
Double Hydroxides

The Thermal Decomposition Behavior of Graphene Oxide/HMX Composites

2015 ◽  
Vol 645-646 ◽  
pp. 110-114 ◽  
Author(s):  
Gui Yu Zeng ◽  
Jian Hua Zhou ◽  
Cong Mei Lin
Keyword(s):  
Activation Energy ◽  
Thermal Decomposition ◽  
Graphene Oxide ◽  
Interlayer Space ◽  
Decomposition Process ◽  
Thermal Decomposition Process ◽  
Hummers Method ◽  
Thermal Decomposition Behavior ◽  
Decomposition Behavior ◽  
Decomposition Activation Energy

Graphene oxide (GO) was prepared by Hummers method and GO/1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) composite was prepared via an ultrasonic compounding method. The structure of GO was characterized using XRD and SEM, the thermal decomposition of HMX and GO/HMX composite was analyzed by DSC/TG test. The results show that interlayer space of GO increases markedly, the thermal decomposition process of HMX can be promoted with the nanolayer structure of GO, resulting the reduced thermal decomposition activation energy of about 50 kJ/mol with 1% GO.

scholarly journals Thermal Decomposition Behavior of 3D Printing Filaments Made of Wood-filled Polylactic Acid (PLA)/Starch Blend

2020 ◽  
Author(s):  
Yufeng Sun ◽  
Danbee Lee ◽  
Yapeng Wang ◽  
Suiliang Li ◽  
Jilai Ying ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
3D Printing ◽  
Polylactic Acid ◽  
Starch Content ◽  
Wood Composites ◽  
Thermal Decomposition Process ◽  
Method Of Calculation ◽  
Thermal Decomposition Behavior ◽  
Decomposition Behavior ◽  
Degradation Degree

Dynamic thermogravimetric (TG) analysis under nitrogen environment was used to understand the thermal decomposition process of 3D printing filaments made of wood-filled polylactic acid (PLA)/starch blend. The characteristic temperatures and apparent activation energy (AAE) of the filaments with various starch contents were calculated with well-known kinetic models by Friedman, Flynn-Wall-Ozawa, Coats-Redfern and Kissinger. With the increased starch content in the filament, the onset thermal decomposition temperatures of the filaments decreased gradually from 272.4 to 155.1°C. The thermal degradation degree became smaller, and the transitional temperature interval became larger with increased starch proportion. The AAE values of the three types of filaments with different starch ratios varied between 97 kJ/mol and 114 kJ/mol, depending on material composition and method of calculation. The improved understanding of thermal decomposition behavior of PLA-starch-wood composites can help develop more biodegradable PLA/starch-based filaments for 3D printing.

scholarly journals Kinetic Analysis of the Thermal Decomposition of a Synthetic Mercury Jarosite

Minerals ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 200 ◽  
Author(s):  
Mizraim Flores ◽  
Iván Reyes ◽  
Elia Palacios ◽  
Francisco Patiño ◽  
Julio Juárez ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Thermal Decomposition ◽  
Environmental Concern ◽  
Frequency Factor ◽  
X Ray Diffraction ◽  
Thermal Decomposition Process ◽  
X Ray ◽  
The Third ◽  
Mercury Oxide

Jarosites are widely used in the hydrometallurgical industry of zinc to eliminate iron and other impurities contained in the concentrates. However, these compounds can also incorporate elements of significant environmental concern such as Tl+, Hg2+, Pb2+, Cd2+, Cr(VI), and As(V). In this work, the characterization of a synthetic mercury jarosite and its thermal decomposition kinetics are reported. XRD and FTIR analyses confirm that a mercury jarosite—Hg0.40(H3O)0.2]Fe2.71(SO4)2.17(OH)4.79(H2O)0.44—was successfully synthesized. Four mass loss events were observed by thermogravimetric analysis at 290 °C, 365 °C, 543 °C, and 665 °C. The third event corresponds to mercury decomposition into mercury oxide, whilst the forth is related to the jarosite to hematite transformation determined by X-ray diffraction starting at around 600 °C. According to the kinetic parameters (activation energy and frequency factor) of the thermal decomposition process, the fourth stage required the highest energy (Ea = 234.7 kJ∙mol−1), which corresponds to elimination of sulfur and oxygen from the jarosite lattice. Results show that jarosite-type compounds have the capability to incorporate heavy metals into their structure, retaining them even at high temperatures. Therefore, they can be used as a remediation strategy for heavy metals, such as mercury and others elements of environmental concern.

scholarly journals Obtaining hydroxyapatite with different precursors for application as a biomaterial

Cerâmica ◽  
2019 ◽  
Vol 65 (373) ◽  
pp. 99-106
Author(s):  
K. A. S. Farias ◽  
W. J. B. Sousa ◽  
M. J. B. Cardoso ◽  
R. J. S. Lima ◽  
M. A. Rodriguez ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Thermal Decomposition ◽  
Fourier Transform ◽  
Calcium Oxide ◽  
Crystal Size ◽  
X Ray Diffraction ◽  
Thermal Decomposition Process ◽  
X Ray ◽  
Scanning Electron

Abstract The hydroxyapatite (HAp) is a ceramic biomaterial with wide application in the bone regeneration. It can be obtained by different routes and different precursors. In this study, the synthesis of HAp was carried out by precipitation and subsequent thermal treatment using different calcium precursors: calcium hydroxide from synthetic origin and calcium oxide obtained from the eggshell. The obtained materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared (FTIR) spectroscopy. By SEM, variations of the crystal size and the concentration of agglomerates were observed. FTIR and XRD analyses proved the formation of HAp and how the (mineral and biological) precursors affected the microstructure. The thermal decomposition process of the calcium oxide obtained from the eggshell showed to be more effective for the synthesis of the hydroxyapatite, resulting in more stable morphology and microstructure.

A β-ketoiminato palladium(II) complex for palladium deposition

2019 ◽  
Vol 74 (11-12) ◽  
pp. 901-912 ◽  
Author(s):  
Andrea Preuß ◽  
Marcus Korb ◽  
Tobias Rüffer ◽  
Jörn Bankwitz ◽  
Colin Georgi ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Deposition Time ◽  
Substrate Surface ◽  
Bond Formation ◽  
X Ray Diffraction ◽  
Hydrogen Bond Formation ◽  
Polydentate Ligand ◽  
X Ray ◽  
Thermal Decomposition Behavior ◽  
Decomposition Behavior

AbstractThe ¦-ketoiminato complex [Pd(OAc)L] (3) can be synthesized by the reaction of bis(benzoylacetone)diethylenetriamine (1, = LH) with [Pd(OAc)2] (2). The structure of 3 in the solid state has been determined by single X-ray diffraction analysis. Complex 3 crystallizes as a dimer (32), which is formed by hydrogen bonds between NH and OOAc functionalities of two adjacent ligands. Each of the Pd atoms is complexed by one ON2 donor unit of the polydentate ligand L− and an acetate group. Pd–Pd interactions and hydrogen bond formation between a NH and the C=O acetate moiety lead to a [4 + 2] coordination at Pd. The non-coordinated part of L exists in its ¦-keto-enamine form. The thermal decomposition behavior of 32 was studied by TG (thermogravimetry) and TG-MS showing that 32 decomposes between 200 and 500°C independent of the applied atmosphere. Under oxygen PdO is produced, while under argon Pd is formed as confirmed by PXRD measurements. Complex 32 was applied as a spin-coating precursor (conc. 0.1 mol L−1, volume 1.5 mL, 3000 rpm, deposition time 6 min, heating rate 50 K min−1, holding time 60 min (Ar) and 120 min (air) at T = 800°C). The as-obtained samples are characterized by granulated particles of Pd/PdO on the substrate surface. EDX (energy-dispersive X-ray spectroscopy) and XPS (X-ray photoelectron spectroscopy) measurements confirmed the formation of Pd (Ar) or PdO (O2) with up to 12 mol% C impurity.

Study on the Thermal Decomposition Behavior of MgAl-Hydrotalcite Compounds

2010 ◽  
Vol 152-153 ◽  
pp. 1451-1456
Author(s):  
Run Sheng Yao ◽  
Xu Wu ◽  
Ya Li Du ◽  
Xian Mei Xie ◽  
Zhi Zhong Wang
Keyword(s):  
Thermal Decomposition ◽  
Kinetic Parameters ◽  
Ozawa Method ◽  
Dynamic Distribution ◽  
Thermal Decomposition Behavior ◽  
Decomposition Procedure ◽  
Ft Ir ◽  
Decomposition Behavior ◽  
Two Stages ◽  
Relative Theory

MgAl-hydrotalcite compounds (MgAl-HT) with different n(Mg)/n(Al) ratios were synthesized by coprecipitation method. XRD and FT-IR were performed to characterize the structure of MgAl-HT. TG-DTG technology was adopted to study the thermal decomposition behavior. It was discovered that the thermal decomposition proceeded in two stages when the ratios of n(Mg) toward n(Al) being to 2~4. The kinetic parameters of the thermal decomposition procedure were also calculated by Ozawa method, which demonstrated that the value of active energy showed dynamic distribution. At each step of the decomposition behavior, the value of active energy decreased at first and then rose. The value of active energy for the deformation of the water in the interlayer was located within 45~90 kJ•mol-1 and within 150~230 kJ•mol-1 for the deformation of structure hydroxyl. Those characteristics were discussed and explained according to relative theory.

Facile solid-phase synthesis of the diammoniate of diborane and its thermal decomposition behavior

2011 ◽  
Vol 13 (16) ◽  
pp. 7508 ◽  
Author(s):  
Zhanzhao Fang ◽  
Junhong Luo ◽  
Xiangdong Kang ◽  
Haijie Xia ◽  
Sisheng Wang ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Solid Phase Synthesis ◽  
Solid Phase ◽  
Phase Synthesis ◽  
Thermal Decomposition Behavior ◽  
Decomposition Behavior

scholarly journals Study of GaN-Based Thermal Decomposition in Hydrogen Atmospheres for Substrate-Reclamation Processing

Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2082
Author(s):  
Shih-Yung Huang ◽  
Jian-Cheng Lin ◽  
Sin-Liang Ou
Keyword(s):  
Thermal Decomposition ◽  
Decomposition Reaction ◽  
Hydrogen Atmosphere ◽  
Thermal Decomposition Process ◽  
Hydrogen Flow ◽  
Thermal Decomposition Behavior ◽  
Transmission Electron ◽  
Furnace Tube ◽  
Decomposition Behavior ◽  
Patterned Sapphire Substrates

This study investigates the thermal decomposition behavior of GaN-based epilayers on patterned sapphire substrates (GaN-epi/PSSs) in a quartz furnace tube under a hydrogen atmosphere. The GaN-epi/PSS was decomposed under different hydrogen flow rates at 1200 °C, confirming that the hydrogen flow rate influences the decomposition reaction of the GaN-based epilayer. The GaN was completely removed and the thermal decomposition process yielded gallium oxyhydroxide (GaO2H) nanostructures. When observed by transmission electron microscopy (TEM), the GaO2H nanostructures appeared as aggregates of many nanograins sized 2–5 nm. The orientation relationship, microstructure, and formation mechanism of the GaO2H nanostructures were also investigated.

Sign in / Sign up

Export Citation Format

Share Document