Ammonium Nitrate Temperature-Programmed Decomposition on Fe-Zeolite Catalysts: Effect of Deposition Method

ChemCatChem ◽  
2017 ◽  
Vol 9 (12) ◽  
pp. 2339-2343 ◽  
Author(s):  
Mafalda Valdez Lancinha Pereira ◽  
David Berthout ◽  
Carolina Petitto ◽  
Gérard Delahay ◽  
Stéphane Raux ◽  
...  
Keyword(s):  
Ammonium Nitrate ◽  
Zeolite Catalysts ◽  
Deposition Method ◽  
Temperature Programmed ◽  
Temperature Programmed Decomposition

scholarly journals Conversion of jet biofuel range hydrocarbons from palm oil over zeolite hybrid catalyst

2021 ◽  
Vol 11 ◽  
pp. 184798042098153
Author(s):  
Norsahika Mohd Basir ◽  
Norkhalizatul Akmal Mohd Jamil ◽  
Halimaton Hamdan
Keyword(s):  
Palm Oil ◽  
Aromatic Hydrocarbons ◽  
Zeolite Y ◽  
Zeolite Catalysts ◽  
Gas Chromatography Mass Spectrometry ◽  
Chemical Compositions ◽  
Hybrid Catalyst ◽  
X Ray Diffraction ◽  
Temperature Programmed ◽  
Reaction Routes

The catalytic conversion of palm oil was carried out over four zeolite catalysts—Y, ZSM-5, Y-ZSM-5 hybrid, and Y/ZSM-5 composite—to produce jet biofuel with high amount of alkanes and low amount of aromatic hydrocarbons. The zeolite Y-ZSM-5 hybrid catalyst was synthesized using crystalline zeolite Y as the seed for the growth of zeolite ZSM-5. Synthesized zeolite catalysts were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, and temperature programmed desorption of ammonia, while the chemical compositions of the jet biofuel were analyzed by gas chromatography-mass spectrometry (GC-MS). The conversion of palm oil over zeolite Y resulted in the highest yield (42 wt%) of jet biofuel: a high selectivity of jet range alkanes (51%) and a low selectivity of jet range aromatic hydrocarbons (25%). Zeolite Y-ZSM-5 hybrid catalyst produced a decreased percentage of jet range alkane (30%) and a significant increase in the selectivity of aromatic hydrocarbons (57%). The highest conversion of palm oil to hydrocarbon compounds was achieved by zeolite Y-ZSM-5 hybrid catalyst (99%), followed by zeolite Y/ZSM-5 composite (96%), zeolite Y (91%), and zeolite ZSM-5 (74%). The reaction routes for converting palm oil to jet biofuel involve deoxygenation of fatty acids into C15–C18 alkanes via decarboxylation and decarbonylation, catalytic cracking into C8–C14 alkanes, and cycloalkanes as well as aromatization into aromatic hydrocarbon.

scholarly journals THERMAL DECOMPOSITION OF BARZAS COALS

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.

scholarly journals New Insight into the In Situ SO2 Poisoning Mechanism over Cu-SSZ-13 for the Selective Catalytic Reduction of NOx with NH3

Catalysts ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1391
Author(s):  
Yu Qiu ◽  
Chi Fan ◽  
Changcheng Sun ◽  
Hongchang Zhu ◽  
Wentian Yi ◽  
...  
Keyword(s):  
Selective Catalytic Reduction ◽  
Active Sites ◽  
Catalytic Reduction ◽  
Zeolite Catalysts ◽  
So2 Poisoning ◽  
Negative Effect ◽  
Temperature Programmed ◽  
Diffuse Reflectance Infrared ◽  
Sulfate Species

To reveal the nature of SO2 poisoning over Cu-SSZ-13 catalyst under actual exhaust conditions, the catalyst was pretreated at 200 and 500 °C in a flow containing NH3, NO, O2, SO2, and H2O. Brunner−Emmet−Teller (BET), X-ray diffraction(XRD), thermo gravimetric analyzer (TGA), ultraviolet Raman spectroscopy (UV Raman), temperature-programmed reduction with H2 (H2-TPR), temperature-programmed desorption of NO+O2 (NO+O2-TPD), NH3-TPD, in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS), and an activity test were utilized to monitor the changes of Cu-SSZ-13 before and after in situ SO2 poisoning. According to the characterization results, the types and generated amount of sulfated species were directly related to poisoning temperature. Three sulfate species, including (NH4)2SO4, CuSO4, and Al2(SO4)3, were found to form on CZ-S-200, while only the latter two sulfate species were observed over CZ-S-500. Furthermore, SO2 poisoning had a negative effect on low-temperature selective catalytic reduction (SCR) activity, which was mainly due to the sulfation of active sites, including Z2Cu, ZCuOH, and Si-O(H)-Al. In contrast, SO2 poisoning had a positive effect on high-temperature SCR activity, owing to the inhibition of the NH3 oxidation reaction. The above findings may be a useful guideline to design excellent SO2-resistant Cu-based zeolite catalysts.

Temperature programmed decomposition of cobalt ethylene diamine complexes

1999 ◽  
Vol 334 (1-2) ◽  
pp. 141-148 ◽  
Author(s):  
S Dash ◽  
P.K Ajikumar ◽  
M Kamruddin ◽  
A.K Tyagi
Keyword(s):  
Ethylene Diamine ◽  
Temperature Programmed ◽  
Temperature Programmed Decomposition

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

2007 ◽  
Vol 534-536 ◽  
pp. 937-940 ◽  
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.

Effect of Supports on the Properties of Co-Mo Nitride Catalysts for Ammonia Decomposition

2011 ◽  
Vol 391-392 ◽  
pp. 1215-1219 ◽  
Author(s):  
Zhao Hui Zhao ◽  
Han Bo Zou ◽  
Wei Ming Lin
Keyword(s):  
Elevated Temperatures ◽  
Active Species ◽  
Ammonia Decomposition ◽  
Zeolite Catalysts ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
5A Zeolite ◽  
Temperature Programmed ◽  
Temperature Programmed Reaction ◽  
Effect Of Support

Supported Co–Mo nitride catalysts have been synthesized by incipient-wetness impregnation method and temperature-programmed reaction in N2-H2 mixed gases. The effect of support types, namely carbon nanotubes(CNTs), active carbon(AC), 5A zeolite and Al2O3 on the properties of the prepared catalysts for ammonia decomposition has been investigated by XRD, H2–TPR and SEM techniques. The results showed that CNTs was the optimum support for Co–Mo nitride catalyst. At 550 , NH3 conversions over CoMoNx/AC, CoMoNx/Al2O3 and CoMoNx/5A Zeolite catalysts were only 14.7%, 65.4% and 68.7%, respectively, while NH3 conversion over CoMoNx/CNTs catalyst was up to 84.4%. XRD and H2–TPR results indicated that the active species consist of CoMoO4, MoO3, γ-Mo2N and Co3Mo3N crystallites, which can be reduced at elevated temperatures at H2 atmosphere. The SEM characterization demonstrated that Co-Mo nitrides particles disperse uniformly on the CNTs.

scholarly journals Speciation of mercury in fly ashes by temperature programmed decomposition

2011 ◽  
Vol 92 (3) ◽  
pp. 707-711 ◽  
Author(s):  
M. Antonia Lopez-Anton ◽  
Ron Perry ◽  
Patricia Abad-Valle ◽  
Mercedes Díaz-Somoano ◽  
M. Rosa Martínez-Tarazona ◽  
...  
Keyword(s):  
Fly Ashes ◽  
Temperature Programmed ◽  
Temperature Programmed Decomposition
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