Catalytic Steam Reforming of Propane over Ni/LaAlO3 Catalysts: Influence of Preparation Methods and OSC on Activity and Stability

Abstract

To develop an efficient catalyst for steam reforming of propane, Ni/LaAlO 3 catalysts were prepared by deposition precipitation, impregnation, and solvo-thermal methods, and characterized by XRD, BET, H 2 -TPR, elemental analyses, and TEM. Ni/Al 2 O 3 and Ni/CeO 2 catalysts were also synthesized by the solvo-thermal method for comparison. The Ni/LaAlO 3 catalysts exhibited better catalytic performance than both Ni/Al 2 O 3 and Ni/CeO 2 catalysts, and activities with Ni/LaAlO 3 were found to be dependent upon the preparation methods. In particular, the Ni/LaAlO 3 catalyst synthesized by the solvo-thermal method exhibited the highest activity presumably because tetrahydrofuran helps distribute generated Ni nanoparticles onto the catalyst surface in a uniform fashion. In addition, the solvo-thermally prepared Ni/LaAlO 3 catalyst was found to be highly stable, with its activity being maintained at least during 100 h. The observed high stability is attributed to the excellent oxygen storage capacity of LaAlO 3 , which was first determined by thermogravimetric methods as well as by soot oxidations in the presence of Al 2 O 3 , CeO 2 , and LaAlO 3 . Compared to the Ni/Al 2 O 3 and Ni/CeO 2 catalysts, Ni/LaAlO 3 exhibited suppressed carbon formation even at lower S/C ratios due to the superior oxygen transport ability of the LaAlO 3 support.

Effect of interactions between Ni and Mo on catalytic properties of a bimetallic Ni-Mo/Al 2 O 3 propane reforming catalyst

“…Generally, these structural interactions may be of a textural nature affecting the physical properties of the Ni catalyst such as metal dispersion or metal crystal surface area [13][14][15] or they may be of an electronic nature, changing electronic densities of different catalyst components, and hence affecting the adsorption and chemical interactions of these components with different reaction intermediates [16,17]. Although these interactions may be established at the onset of the reaction [4,6,18,19], the nature of these interactions may change during time on stream.…”

Enhancement of soot oxidation activity of manganese oxide (Mn2O3) through doping by the formation of Mn1.9M0.1O3–δ (M = Co, Cu, and Ni)

“…Mn 2 O 3 and M‐doped catalysts (Mn 1.9 M 0.1 O 3– δ : M = Co, Cu, and Ni) were synthesized by coprecipitation method . Typically, to prepare 2 g of the Mn 1.9 Co 0.1 O 3– δ sample, 2.05 g of cobalt(II) nitrate hexahydrate (Co(NO 3 ) 2 ·6H 2 O, 291 g/mol) and 16.77 g of manganese(II) nitrate tetrahydrate (Mn(NO 3 ) 2 ·4H 2 O, 251.01 g/mol) salts were taken in aqueous form.…”

“…Cu, and Ni) were synthesized by coprecipitation method. 25 Typically, to prepare 2 g of the Mn 1.9 Co 0.1 O 3-δ sample, 2.05 g of cobalt(II) nitrate hexahydrate (Co(NO 3 ) 2 ·6H 2 O, 291 g/mol) and 16.77 g of manganese(II) nitrate tetrahydrate (Mn(NO 3 ) 2 ·4H 2 O, 251.01 g/mol) salts were taken in aqueous form. This metal solution was precipitated by dropwise addition of sodium hydroxide (NaOH) until pH reached 10.…”

Structurally-functional design of nanocomposite catalysts for producing and environmental catalysis

“…Формирование кристаллической структуры происходит при более высоких температурах, что может быть связано с полным удалением нитрат-анионов. катализаторов может также заключаться в том, что высокая лабильность кислорода в их структуре позволяет аккумулировать О 2 и регулировать его концентрацию в зоне катализа за счет эффекта накопительной емкости по кислороду [18], что обеспечивает устойчивую работу катализатора в кислородсодержащей среде при осуществлении процесса ТРМ [16].…”