Ce-introduced effects on modification of acidity and Pt electronic states on Pt-Sn/γ-Al2O3 catalysts for catalytic reforming

CeO2-Promoted PtSn/SiO2 as a High-Performance Catalyst for the Oxidative Dehydrogenation of Propane with Carbon Dioxide

“…As shown in Figure 5 b, the Sn 3d 5/2 at about 487.0 eV was deconvoluted to analyze the chemical state of Sn. In the case of PtSn/SiO 2 , a symmetric Sn 3d 5/2 XPS peak with a binding energy of 487.2 eV was observed, indicating the presence of only SnO x species, as reported in [ 28 ]. However, besides oxide species, a small amount of Sn 0 species located at 485.7 eV was observed over PtSnCe/SiO 2 .…”

“…As for the reason, it is noteworthy that PtSnCe/SiO 2 showed a slightly higher content of Pt 0 than PtCe/SiO 2 ( Table 2 ), which may originate from the improved interaction between SnO 2 and Pt due to the presence of CeO 2 . This coincides well with the presence of Sn 0 species, indicating the possible formation of Pt-Sn bimetallic nanoparticles [ 28 , 43 ].…”

“…In the case of PtSnCe/SiO 2 and PtCe/SiO 2 , CO was the predominant byproduct, while the selectivity of C 2 H 6 , C 2 H 4 , and CH 4 was very low. This indicates that CO 2 -RP may be the main side reaction over these catalysts in comparison with cracking [ 13 , 28 ]. The significantly higher CO selectivity of 56.9% at a TOS of 5 min was observed over PtCe/SiO 2 , indicating the more favorable breaking of C-C bonds in propane.…”

Regulating Encapsulation of Small Pt Nanoparticles inside Silicalite-1 Zeolite with the Aid of Sodium Ions for Enhancing n-Hexane Reforming

“…Aromatic hydrocarbons, especially benzene, toluene, and xylenes (BTX), are important basic building blocks of the chemical industry. , Currently, these compounds are mainly produced from the reforming of naphtha feedstocks . However, traditional petroleum refining processes cannot meet the continually increasing demand for aromatics in industry.…”

“…The size of metal particles is one of the key factors in determining the performance of the reforming of straight-chain alkanes. Generally, metal clusters or/and single atoms have better catalytic properties than metal particles due to the exposure of more accessible active sites and improvement of the charge transfer between metal and support and/or other metals. − Among these catalysts, Pt supported on chlorine-containing alumina (Pt/Al 2 O 3 –Cl) is the common commercial catalyst for naphtha reforming and it is efficient for the transformation of C 8 and higher alkanes to aromatics. ,− However, it is hard to convert C 6 or C 7 alkane over Pt/Al 2 O 3 –Cl. Moreover, Pt/Al 2 O 3 –Cl belongs to a metal-acid bifunctional catalyst, which is prone to bring about some side reactions such as isomerization and cracking over the acid sites, thus resulting in low aromatics selectivity. − In addition, the reforming process of n-alkanes is thermodynamically limited and highly endothermic, so a high reaction temperature is required to reach a reasonable conversion.…”