Hydrogen production via water-gas shift reaction over gold supported on Ni-based layered double hydroxides. (1st January 2021)

• Record Type: Journal Article
• Authors: Gabrovska, Margarita; Ivanov, Ivan; Nikolova, Dimitrinka; Kovacheva, Daniela; Tabakova, Tatyana
• Is Part Of: International journal of hydrogen energy. Volume 46:Number 1(2021)
• Page Start: 458
• Page End: 473
• Publication Date: 2021-01-01
• Subjects: NiAl layered double hydroxides -- Magnesium additive -- Gold catalysts -- Hydrogen production -- Water-gas shift reaction; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2020.09.214
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Co-precipitated NiAl and NiMgAl layered double hydroxides (LDHs) were prepared at M 2+ /Al 3+ molar ratio of 2.5/1 and subsequently promoted with gold targeting to be studied as catalysts and supports of gold particles in the hydrogen production via water-gas shift (WGS) reaction. Powder X-ray diffraction and N2 physisorption before and after WGS tests were applied to investigate the impacts of Mg and Au on the structure and catalytic behavior of the systems. Partial replacement of Ni by Mg resulted in moderate activity of NiMgAl and Au/NiMgAl catalysts than NiAl analogues due to: (i) smaller Ni amount that could not supply sufficient number catalytically active sites; (ii) higher thermal stability leading to the creation of the active Ni species at higher temperatures, and (iii) partial regeneration of the layered structure with the assistance of small Au particles, Mg, and the reaction medium as well. Favorable role of gold on Au/NiAl WGS activity was elucidated. Graphical abstract: Image 1 Highlights: Nanosized Ni-based LDHs were studied as water-gas shift (WGS) catalysts. Gold deposition leads to respectable WGS performance of NiAl LDH. Partial substitution of Ni by Mg changes texture, thermal stability and reducibility. Moderate Au/NiMgAl activity is related to partial regeneration of initial structure. Hydrogen production via WGS is affected by Ni and Au amounts, and Mg presence.