Highly Selective and Stable NiSn/SiO₂ Catalyst for Isobutane Dehydrogenation: Effects of Sn Addition

Abstract

Ni/SiO2 catalysts with large surface area Ni particles exhibit high hydrogenolysis activity, leading to the formation of large amounts of methane and coke. To destroy the active sites for hydrogenolysis, namely the aggregated Ni ensembles, Sn species were introduced into the Ni/SiO2 catalyst. As expected, isobutene selectivity was significantly increased to 90.2 %. The promoting role of Sn on the dehydrogenation performance could be interpreted as both a geometric and electronic effect. On one hand, Sn addition efficiently dispersed aggregated Ni particles and reduced Ni particle size from 77 to 16 nm, weakening the ability of Ni for C−C bond rupture. On the other hand, additional electrons provided by Sn led to a high electronic density of Ni, facilitating the desorption of isobutene from the catalyst and suppressing secondary reactions. Consequently, coke formation was effectively inhibited over the NiSn/SiO2 catalyst, further guaranteeing a good stability and prolonged cycle time.

Ketone Formation from Carboxylic Acids by Ketonic Decarboxylation: The Exceptional Case of the Tertiary Carboxylic Acids

“…(6)]. [38][39][40] However,h aving in mind the product ratios, it becomes evidentt hat further sources (precursors) for the methane formation must exist. Once formed, isobutane mayb ef ragmented into propene and methane [Eq.…”

“…Such fragmentation has been observed at high temperatureo ver solid materials. [38][39][40] However,h aving in mind the product ratios, it becomes evidentt hat further sources (precursors) for the methane formation must exist. For the liquid carbonyl compounds, formationb yk etonic decarboxylation was assumed as aw orking hypothesis.…”

Tetrahedral Nickel(II) Phosphosilicate Single‐Site Selective Propane Dehydrogenation Catalyst

“…Under these conditions, supported Ni catalysts are reduced to Ni 0 nanoparticles, which usually show poor stability, fast coke deposition, high methane selectivity, and low alkene selectivity . To improve the stability and selectivity, several Ni‐based catalysts have been studied, including NiSn, NiS, and NiP for the isobutane dehydrogenation reaction . NiAu bimetallic catalysts have been studied for the more challenging propane dehydrogenation reaction .…”

Effect of preparation method on the bimetallic NiCu/SAPO-11 catalysts for the hydroisomerization of n-octane

“…They suggested that the ligand and ensemble effects of P resulted in the low hydrogenolysis activity. Wang et al [19] studied the isobutane dehydrogenation over the NiSn/SiO 2 catalyst. They found that the addition of Sn effectively restrained the hydrogenolysis activity.…”