Speciation of mercury in fly ashes by temperature programmed decomposition

Cenospheres from coal fly ashes were used as support in the preparation of Ni–Mg catalysts for dry reforming of methane. These materials were characterized by means of XRD, H2-temperature-programmed reduction (H2-TPR), CO2-temperature-programmed desorption (CO2-TPD), and low-temperature nitrogen sorption techniques. The cenosphere-supported catalysts showed relatively high activity and good stability in the dry reforming of methane (DRM) at 700 °C. The catalytic performance of modified cenospheres was found to depend on both Ni and Mg content. The highest activity at 750 °C and 1 atm was observed for the catalyst containing 30 wt % Mg and 10, 20, and 30 wt % Ni, yielding to CO2 and CH4 conversions of around 95%.

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THERMAL DECOMPOSITION OF BARZAS COALS

IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA ◽

10.6060/ivkkt.20216403.6297 ◽

2021 ◽

Vol 64 (3) ◽

pp. 92-99

Author(s):

Ivan Ya. Petrov ◽

Boris G. Tryasunov ◽

Alexander R. Bogomolov ◽

Konstantin Yu. Ushakov ◽

Alexander S. Zyabrev

Keyword(s):

Thermal Decomposition ◽

Temperature Region ◽

Adsorbed Water ◽

Volatile Components ◽

Coal Pyrolysis ◽

Helium Atmosphere ◽

Mineral Components ◽

Temperature Programmed ◽

Temperature Programmed Decomposition ◽

Coal Organic Matter

Thermal decomposition processes of two types of Barzas sapromixites - a tile-like modification (“tile”) and a product of its weathering (“exfoliated tile”) - have been investigated in various media (air and helium). It has been shown that in the course of temperature-programmed decomposition (10 °C/min) of these forms of tile-like Barzas sapromixite, in both oxidizing (air) and inert (helium) atmospheres, four main temperature ranges can be distinguished: 1) < 150 °C - removal of adsorbed water (this temperature region is more pronounced for the weathered form of tile-like Barzas sapromixite); 2) 150-350 °C - removal of low molecular weight volatile components of coal in helium environment (with their simultaneous ignition in case of the decomposition in air); 3) 350-550 °C - the temperature region of primary or fast coal pyrolysis in an inert medium; in an oxidative medium, this stage of pyrolysis is accompanied by the burning of released tarry substances; 4) > 550 °C - the temperature region of secondary or high-temperature coal pyrolysis to form semi-coke in helium atmosphere, or the region of burning this semi-coke in air medium. Thermal breakdown processes of “exfoliated tiles” in the temperature range of the most intensive decomposition (350-550 °C) have been found to require less energy consumptions than the similar processes for tile-like Barzas coals (by 72-73 kJ/mol for both gas media of thermal treatment). It is supposed that the differences observed in thermal behavior of Barzas sapromixite forms under investigation may be related to the different contents of mineral components and their effects on the thermal decomposition of coal organic matter.

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ChemInform Abstract: HIGH METHANE FORMATION DURING THE TEMPERATURE-PROGRAMMED DECOMPOSITION IN FLOWING HYDROGEN OF SUPPORTED MONONUCLEAR AND POLYNUCLEAR CARBONYL COMPLEXES

Chemischer Informationsdienst ◽

10.1002/chin.198116293 ◽

1981 ◽

Vol 12 (16) ◽

Author(s):

D. A. HUCUL ◽

A. BRENNER

Keyword(s):

Methane Formation ◽

Carbonyl Complexes ◽

Flowing Hydrogen ◽

Temperature Programmed ◽

Temperature Programmed Decomposition

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Temperature programmed decomposition of cobalt ethylene diamine complexes

Thermochimica Acta ◽

10.1016/s0040-6031(99)00186-0 ◽

1999 ◽

Vol 334 (1-2) ◽

pp. 141-148 ◽

Cited By ~ 8

Author(s):

S Dash ◽

P.K Ajikumar ◽

M Kamruddin ◽

A.K Tyagi

Keyword(s):

Ethylene Diamine ◽

Temperature Programmed ◽

Temperature Programmed Decomposition

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A Study on Kinetics Parameters of Titanium Hydride Powder from Its TPD Spectrum for Metal Foam

Materials Science Forum ◽

10.4028/www.scientific.net/msf.534-536.937 ◽

2007 ◽

Vol 534-536 ◽

pp. 937-940 ◽

Cited By ~ 1

Author(s):

Dong Hui Yang ◽

Sang Youl Kim ◽

Bo Young Hur

Keyword(s):

Titanium Hydride ◽

Metal Foam ◽

Al Alloy ◽

Superposition Method ◽

Kinetics Parameters ◽

Foaming Process ◽

Titanium Hydride Powder ◽

Temperature Programmed ◽

Set Up ◽

Temperature Programmed Decomposition

In this paper, the whole temperature programmed decomposition (TPD) spectrum of titanium hydride was acquired by the special designed set-up. After separating and simulating the TPD spectrum by using Spectrum Superposition Method (SSM), Consulting Table Method (CTM) and differential spectrum technique, the kinetics parameters of titanium hydride and corresponding equations were obtained. Using these kinetics equations, the fabrication parameters of Al alloy foam can be determined and foaming process of Al alloy melt can be predicted.

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