Crystallization of Ammonium Heptamolybdate for Reduction to Mo Metal

2021 ◽  
Author(s):  
Anna Servis ◽  
David Bettinardi ◽  
Peter Tkac
Keyword(s):  
Ammonium Heptamolybdate

Methanation on exfoliated and supported MoS2

1989 ◽  
Vol 67 (5) ◽  
pp. 862-866 ◽  
Author(s):  
Guenter A. Scholz ◽  
S. Roy Morrison
Keyword(s):  
Activation Energy ◽  
Carbon Monoxide ◽  
Transition Metal Catalysts ◽  
Surface Species ◽  
Reaction Products ◽  
Third Order ◽  
Ammonium Heptamolybdate ◽  
First Order ◽  
Methanation Reaction ◽  
Improved Performance

The methanation reaction on MoS2 exfoliated to a thickness of a few layers or less and adsorbed onto alumina is found to be very small. However, by calcining and resulfiding the exfoliated MoS2 catalysts, greatly improved performance is achieved that is at least equal to the commercial catalysts based on ammonium heptamolybdate. The creation of molybdenum oxysulflde surface species therefore appears to be a necessary step toward producing significant methanation rates with exfoliated and supported MoS2. The methanation products are almost exclusively CO2 and CH4, their mole ratios near unity, with otherwise only very much smaller amounts of longer chain hydrocarbons. The activation energy for methanation is generally observed to be near 100 kJ/mol, with the overall reaction being first order in the carbon monoxide concentration and third order in the hydrogen concentration. In contrast to the transition-metal catalysts, no water could be detected in the reaction products of the molybdenum based catalyst. Keywords: methanation reaction on MoS2, exfoliated and supported MoS2 as catalyst.

Solid-Phase Reaction of Tetraammineplatinum(II) Chloride with Ammonium Heptamolybdate

2020 ◽  
Vol 90 (6) ◽  
pp. 1020-1024
Author(s):  
E. V. Fesik ◽  
T. M. Buslaeva ◽  
T. I. Melnikova ◽  
L. S. Tarasova
Keyword(s):  
Solid Phase ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
Ammonium Heptamolybdate

scholarly journals Comparison of Two Preparation Methods on Catalytic Activity and Selectivity of Ru-Mo/HZSM5 for Methane Dehydroaromatization

2014 ◽  
Vol 2014 ◽  
pp. 1-7
Author(s):  
Lucia M. Petkovic ◽  
Daniel M. Ginosar
Keyword(s):  
Molybdenum Carbide ◽  
Molybdenum Trioxide ◽  
Catalyst Activity ◽  
Catalytic Performance ◽  
Preparation Methods ◽  
Ammonium Heptamolybdate ◽  
Temperature Programmed Oxidation ◽  
Methane Dehydroaromatization ◽  
Acidic Sites ◽  
Temperature Programmed

Catalytic performance of Mo/HZSM5 and Ru-Mo/HZSM5 catalysts prepared by vaporization-deposition of molybdenum trioxide and impregnation with ammonium heptamolybdate was analyzed in terms of catalyst activity and selectivity, nitrogen physisorption analyses, temperature-programmed oxidation of carbonaceous residues, and temperature-programmed reduction. Vaporization-deposition rendered the catalyst more selective to ethylene and coke than the catalyst prepared by impregnation. This result was assigned to lower interaction of molybdenum carbide with the zeolite acidic sites.

Solid-state ion exchange of ammonium heptamolybdate tetrahydrate into ZSM-5 zeolite

2017 ◽  
Vol 131 (2) ◽  
pp. 1295-1306 ◽  
Author(s):  
Faouzi Ayari ◽  
Emna Mannei ◽  
Esther Asedegbega-Nieto ◽  
Mourad Mhamdi ◽  
Antonio Ricardo Guerrero-Ruiz ◽  
...  
Keyword(s):  
Solid State ◽  
Ion Exchange ◽  
Ammonium Heptamolybdate
Sign in / Sign up

Export Citation Format

Share Document