Propane dehydrogenation over Pt–Cu bimetallic catalysts: the nature of coke deposition and the role of copper

Han, Zhao Jun; Li, Shuirong; Jiang, Feng; Wang, Tuo; Ma, Xinbin; Gong, Jinlong

doi:10.1039/c4nr02143f

Cited by 216 publications

(155 citation statements)

References 52 publications

Supporting

Mentioning

148

Contrasting

Unclassified

Order By: Relevance

“…Figure S16 shows the TEM image of spent catalyst. [49,50] One can see that the obvious thermal decomposition of coke occurred in the range of 450-625 8C for the 0.5 wt%Mg-1 wt%Cu/b-zeolite but this decomposition temperature was in the range of 550-750 8C for 1 wt%Cu/b-zeolite, indicating that Mg loading retarded the hard coke formation. The coke morphologies exhibited the appearance of wormhole-like structure with significant disorder of pore arrangement, corresponding to the feature of amorphous coke.…”

Section: Catalyst Stability and Reusabilitymentioning

confidence: 99%

Bifunctional Mg−Cu‐Loaded β‐Zeolite: High Selectivity for the Conversion of Furfural into Monoaromatic Compounds

et al. 2018

View full text Add to dashboard Cite

MgÀCu-loaded b-zeolite was prepared as an acidÀbase bifunctional catalyst for the conversion of furfural to monoaromatic compounds. It is found that this catalyst exhibited high selectivity towards benzene, toluene and xylenes (BTXs) production with anti-polycyclic-aromatic-hydrocarbon formation as well as anti-coking ability when compared with Culoaded b-zeolite and the parent b-zeolite. The product distribution indicated that addition of Cu species significantly promoted the deoxygenation and aromatization of an intermediate product of furan while Mg apparently suppressed the polyaromatization. Especially, an optimum loading amount of 0.5 wt%Mg-1 wt%Cu on b-zeolite was obtained, which showed lower catalytic deoxygenation temperature and interestingly, only benzene was detected in the liquid product at a reaction temperature over 700 8C. Also, 0.5 wt%Mg-1 wt%Cu/b-zeolite exhibited long-term stability for 10 cycles with 100 % of furfural conversion to monoaromatic compounds. The physicochemical properties of b-zeolite after Cu and Mg loadings were characterized using N 2 sorption, XRD, SEM-EDX, TEM, H 2 -TPR, UV-Vis, XPS, NH 3 -TPD and CO 2 -TPD techniques. The significant changing of acidity and basicity of b-zeolite were found after Cu and Mg loadings, which should be the main factors for the improvement of activity, selectivity and stability of the developed catalyst.[a] Dr. and 750 8C, respectively. This indicates that 1 wt%Cu/ b-zeolite and 0.5 wt%Mg-1wt%Cu/b-zeolite had high selectivity for the benzene production from furfural conversion at a reaction temperature over 700 8C. Based on these results, it can be concluded that the tuning of acid and basic sites of b-zeolite and the interaction of metal species on b-zeolite by co-doping of Mg with Cu, the changing of reaction temperature as well as WHSV can effectively control the product distribution from the furfural conversion.According to the presented results, the possible mechanism for the catalytic conversion of furfural over MgÀCu-doped bzeolite can be proposed following based on previous liter-Figure 4. Effect of WHSV on product yields and aromatic distributions in liquid products obtained from the catalytic deoxygenation of furfural at a reaction temperature of 600 8C and a TOS of 1 h using (A,B) b-zeolite, (C,D) 1wt%Cu/b-zeolite and (E,F) 0.5 wt%Mg-1 wt%Cu/b-zeolite.

show abstract

Section: Catalyst Stability and Reusabilitymentioning

confidence: 99%

Bifunctional Mg−Cu‐Loaded β‐Zeolite: High Selectivity for the Conversion of Furfural into Monoaromatic Compounds

et al. 2018

View full text Add to dashboard Cite

show abstract

“…[11a,b,13] However,noany Ni or Ni oxide peaks were present in XRD or Raman spectra of the Ni-N-C samples (Supporting Information, Figures S1, S2), indicating that the Ni species is highly dispersed. [14] On the other hand, the pyrolysis temperature imposed asignificant effect on both the textural properties and the dispersion of Ni species.T he BET surface areas reached the highest (500 m 2 g À1 )a t6 00 8 8C and then decreased markedly to 376 m 2 g À1 at 700 8 8C, indicating the loss of pores due to structural collapse at higher temperatures (Supporting Information, Figure S3). This phenomenon, however,w as not observed for either Fe-N-C or Co-N-C materials prepared with as imilar procedure, [12] implying that the metal species participated in and probably catalyzed the carbonization process.IfNiNPs were formed at 700 8 8C, they would catalyze the methanation of carbon and then resulted in collapse of porous structure.This speculation was confirmed by low-magnification STEM images (Supporting Information, Figure S4).…”

mentioning

confidence: 99%

A Durable Nickel Single‐Atom Catalyst for Hydrogenation Reactions and Cellulose Valorization under Harsh Conditions

et al. 2018

View full text Add to dashboard Cite

Hydrothermally stable, acid-resistant nickel catalysts are highly desired in hydrogenation reactions, but such a catalyst remains absent owing to the inherent vulnerability of nickel under acidic conditions. An ultra-durable Ni-N-C single-atom catalyst (SAC) has now been developed that possesses a remarkable Ni content (7.5 wt %) required for practical usage. This SAC shows not only high activities for hydrogenation of various unsaturated substrates but also unprecedented durability for the one-pot conversion of cellulose under very harsh conditions (245 °C, 60 bar H , presence of tungstic acid in hot water). Using integrated spectroscopy characterization and computational modeling, the active site structure is identified as (Ni-N4)⋅⋅⋅N, where significantly distorted octahedral coordination and pyridinic N constitute a frustrated Lewis pair for the heterolytic dissociation of dihydrogen, and the robust covalent chemical bonding between Ni and N atoms accounts for its ultrastability.

show abstract

“…[4] High reaction temperatures cause catalyst deactivation by sintering [5] and coke formation. [6] While carbon deposits can be effectively oxidized during regener-ation in air,itismore difficult to achieve redispersion of Pt. [7] In fact, heating Pt/Al 2 O 3 under oxidizing conditions leads to sintering of Pt, forming large Pt particles.…”

mentioning

confidence: 99%

Thermally Stable and Regenerable Platinum–Tin Clusters for Propane Dehydrogenation Prepared by Atom Trapping on Ceria

et al. 2017

View full text Add to dashboard Cite

Ceria (CeO 2 )s upports are unique in their ability to trap ionic platinum (Pt), providing exceptional stability for isolated single atoms of Pt. The reactivity and stability of single-atom Pt species was explored for the industrially important light alkane dehydrogenation reaction. The singleatom Pt/CeO 2 catalysts are stable during propane dehydrogenation, but are not selective for propylene.D FT calculations show strong adsorption of the olefin produced, leading to further unwanted reactions.Incontrast, when tin (Sn) is added to CeO 2 ,t he single-atom Pt catalyst undergoes an activation phase where it transforms into Pt-Sn clusters under reaction conditions.F ormation of small Pt-Sn clusters allows the catalyst to achieve high selectivity towards propylene because of facile desorption of the product. The CeO 2 -supported Pt-Sn clusters are very stable,e ven during extended reaction at 680 8 8C. Coke formation is almost completely suppressed by adding water vapor to the feed. Furthermore,u pon oxidation the Pt-Sn clusters readily revert to the atomically dispersed species on CeO 2 ,m aking Pt-Sn/CeO 2 af ully regenerable catalyst.

show abstract

Propane dehydrogenation over Pt–Cu bimetallic catalysts: the nature of coke deposition and the role of copper

Cited by 216 publications

References 52 publications

Bifunctional Mg−Cu‐Loaded β‐Zeolite: High Selectivity for the Conversion of Furfural into Monoaromatic Compounds

Bifunctional Mg−Cu‐Loaded β‐Zeolite: High Selectivity for the Conversion of Furfural into Monoaromatic Compounds

A Durable Nickel Single‐Atom Catalyst for Hydrogenation Reactions and Cellulose Valorization under Harsh Conditions

Thermally Stable and Regenerable Platinum–Tin Clusters for Propane Dehydrogenation Prepared by Atom Trapping on Ceria

Contact Info

Product

Resources

About