Metal nanoparticles in ionic liquid‐cosolvent biphasic systems as active catalysts for acetylene hydrochlorination

Abstract

Ionic liquid (IL)‐stabilized metal nanoparticles (NPs) have attracted increased attention as novel catalysts for various reactions due to their excellent stability and high activity. However, the high viscosity of ILs limits their applications. Here, for the first time, we reported an NPs@IL‐cosolvent liquid–liquid biphasic system for metal NPs catalysis. The NPs were successfully confined to IL phase, and abundant IL droplets containing NPs were generated under the reactant flow. The NPs@IL droplets served as microreactors for the catalysis; while the low viscosity organic phase enabled the rapid mass transfer of substances. The biphasic system exhibited improved performance for acetylene hydrochlorination than that of the pure IL system. An acetylene conversion of 98% and a selectivity of 99.5% were achieved along with a 90% decrease on IL usage. The tolerable gas hourly space velocity in the biphasic system for a satisfactory conversion was almost double that of the pure IL system. © 2018 American Institute of Chemical Engineers AIChE J, 64: 2536–2544, 2018

Nanostructuring unlocks high performance of platinum single-atom catalysts for stable vinyl chloride production

“…half of the initial catalytic activity of state-of-the-art Au SACs, which is more than three times higher compared to the activity levels reported in literature for platinum-based catalysts, which were likely composed of Pt nanoparticles. 27 , 34 , 36 …”

“…half of the initial catalytic activity of state-of-the-art Au SACs, which is more than three times higher compared to the activity levels reported in literature for platinum-based catalysts, which were likely composed of Pt nanoparticles. 27,34,36 Mechanistic studies. To gain atomistic insight into the structure-performance relationships of distinct Pt sites in acetylene hydrochlorination, DFT was employed.…”

“…40% lower price compared to Au, 28 rendering it appealing from an industrial perspective. However, to date there are only a few studies on Pt-based catalysts for acetylene hydrochlorination, 27 , 34 – 36 likely due to the ca . 7 times lower catalytic activity compared to Au-based systems, which might have discouraged detailed investigations into this metal.…”

Amphiphilic Super-Wetting Ionic-Liquid-Based Lower Critical Solution Temperature System: Preparation, Characterization, and Excellent Dispersion Performance for Nanostructured Materials

“…26−28 The LCC-ILs were prepared via anion exchange of the corresponding phosphonium bromide to phosphonium hydroxide and subsequent neutralization with long-chain fatty acids. 26,29 The LCC-ILs prepared in this work were all transparent amber liquids at room temperature, and the related viscosity was evaluated from 450 to 600 cP at 298 K (Figure S1). The glass transition temperatures or melting points of the ILs with n-octyltributylphosphonium ([P 4448 ] + ) cations were relatively low (between −80 and −40 °C), while those of the n-dodecyltribultylphophonium ([P 444 (12) ] + )-based ILs were approximately −18 °C (Figure S2).…”

Design strategies for the development of a Pd-based acetylene hydrochlorination catalyst: improvement of catalyst stability by nitrogen-containing ligands

“…Actually, the leaching of the PdCl 2 active component was oen thought to be the cause of deactivation for Pd-based catalysts in the hydrochlorination of acetylene. [44][45][46]51,52 For example, Wang 41 demonstrated that 44.7% Pd species had leached from HY zeolite-supported Pd-based catalysts aer reaction; in addition, Wang suggested that the Pd loss was responsible for the deactivation of the Pd/HY catalysts, and the ICP analysis indicated that about 37.8% Pd species had been lost aer 10 h time on stream as compared to the case of the fresh catalyst. Fig.…”