Improved Hydrothermal Stability of Mesoporous Oxides for Reactions in the Aqueous Phase

Pham, Hien N.; Anderson, Amanda E.; Johnson, Robert L.; Schmidt‐Rohr, Klaus; Datye, Abhaya K.

doi:10.1002/ange.201206675

Cited by 23 publications

(18 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Table 3 From the data in Table 3, it is evident that physical properties associated with support structure do not change significantly between fresh and spent catalysts, and no substantial perturbations in surface area and porosity are observed in any system. Although support hydrothermal stability is critical in aqueous-phase catalysis [39,41], support degradation does not appear to underlie irreversible deactivation in this study. X-Ray Diffraction patterns (online supporting information) do not show a significant change in support structure between pre-and post-reaction samples.…”

Section: Catalyst Stabilitymentioning

confidence: 69%

See 1 more Smart Citation

Toward rational design of stable, supported metal catalysts for aqueous-phase processing: Insights from the hydrogenation of levulinic acid

Abdelrahman

Luo

Heyden

et al. 2015

Journal of Catalysis

View full text Add to dashboard Cite

Aqueous phase hydrogenation of levulinic acid (4-oxopentanoic acid) and 2-pentanone were considered to probe the activity and stability of supported Ru catalysts during ketone hydrogenation in water. Selected supports include activated carbon, amorphous SiO 2 , γ-Al 2 O 3 , and TiO 2. For both probe molecules, intrinsic hydrogenation activity was independent of support identity and Ru particle size. Moreover, the presence of a secondary functional group in levulinic acid (i.e., a carboxyl group) and the resulting dissociated protons do not appear to

show abstract

Section: Catalyst Stabilitymentioning

confidence: 69%

“…The severity of the aqueous phase-and its effect on catalyst stability-has been frequently considered, and prior discussion has largely centered on support hydrothermal stability [38][39][40][41][42].…”

Section: Introductionmentioning

confidence: 99%

Toward rational design of stable, supported metal catalysts for aqueous-phase processing: Insights from the hydrogenation of levulinic acid

Abdelrahman

Luo

Heyden

et al. 2015

Journal of Catalysis

View full text Add to dashboard Cite

show abstract

“…Carbon coating and hybrid atom doping have been used to improve catalyst stability in heterogeneous catalysis [48][49][50]. In this study, we preliminarily investigated two methods for improving the stability of the 3D mesopore MCF supported Co catalysts in FTS carried out at high temperatures.…”

Section: The Stability Of Co Catalysts Supported On 3d Mesoporous Mcfmentioning

confidence: 99%

Fischer–Tropsch synthesis over a 3D foamed MCF silica support: Toward a more open porous network of cobalt catalysts

Liang

Zhao

Zhang

et al. 2016

Journal of Catalysis

View full text Add to dashboard Cite

a b s t r a c tThree-dimensional mesoporous cellular silica foams (MCFs) were prepared and used as supports for cobalt Fischer-Tropsch synthesis (FTS) catalysts (Co/MCF). The silica foam MCFs have a 3D mesostructure with large spherical cell pores interconnected with small window pores, which provides an open porous network for Co FTS catalysts. The effects of catalyst structure parameters (cell pore diameter and cobalt particle size) on the performance of the Co/MCF catalysts were investigated. It was found that the Co/MCF catalyst with average pore size 7-12 nm (window and cell pores) showed the highest reactivity. The MCF not only provided a cavity to suppress the growth of cobalt particles, but also enhanced the reducibility and cobalt dispersion. The Co/MCF catalysts having a large and open pore structure are favorable for the transport of reactants and the occurrence of secondary reactions, leading to high C 5+ hydrocarbon selectivity. A Co/MCF catalyst with Co particle size 6.9 nm presented the highest activity in the FTS reaction due to its having the highest dispersion and an appropriate degree of reduction. Compared with the Co catalysts supported on other ordered silicas (SBA-16, KIT-6, and SBA-15), the Co/MCF catalyst showed higher activity and C 5+ hydrocarbon selectivity, which was attributed to the 3D open porous structure of MCF. The Co/MCF catalysts are stable under low-temperature FTS conditions (210°C). Under harsh FTS reaction conditions (250°C, 1.0 MPa), the Co/MCF catalyst underwent rapid deactivation due to cobalt sintering and the formation of interacting Co-silica compound, while the stability of the Co/MCF catalyst can be improved by functionalizing the MCF using carbon coating and Al doping.

show abstract

“…Pham et al [13,14] developed a method to modify the surfaces of oxidic supports to make them less susceptible to hydrolytic attack at 200°C. The approach involves the deposition of a thin film of carbon obtained by controlled pyrolysis of sugars on commercial SiO 2 .…”

Section: Introductionmentioning

confidence: 99%

Bio-propylene glycol by liquid phase hydrogenolysis of glycerol with Ni/SiO 2 -C catalysts

et al. 2017

View full text Add to dashboard Cite

The development of catalytic materials, hydrothermally stable and selective to the desired products, is still a challenge. The aim of the present work is to prepare a nickel catalyst with a metal loading of 5 wt% Ni supported on a SiO 2-C composite, to be used in the liquid-phase glycerol hydrogenolysis reaction. The most active and selective catalyst to 1,2-propylene glycol (1,2-PG) was Ni/SC-095, which presented surface acidity fundamentally represented by the presence of carboxylic groups which promoted the CeO cleavage reactions of the glycerol primary carbon to produce acetol, and subsequently by hydrogenation to produce 1,2-PG. Concerning the selection of operating conditions, the influence of the most relevant variables of the process were analyzed, i.e., temperature (220-260°C), glycerol concentration (30-65%), and hydrogen partial pressure (0-4 MPa). The best result was obtained at 260°C with 30 wt% glycerol, 6 h on reaction and a hydrogen partial pressure of 2 MPa. Under these conditions, selectivities of 77% towards 1,2-PG and 3% to acetol were obtained, with 56% of conversion. It was demonstrated that there are no important structural changes through the characterization of the used samples. Both the SC-095 support and the Ni/SC-095 catalyst maintained their BET surface area. By XRD and TEM, there could be a slight increase in particle size, which would indicate good resistance to sintering against the severe hydrothermal conditions of this reaction.

show abstract

Improved Hydrothermal Stability of Mesoporous Oxides for Reactions in the Aqueous Phase

Cited by 23 publications

References 10 publications

Toward rational design of stable, supported metal catalysts for aqueous-phase processing: Insights from the hydrogenation of levulinic acid

Toward rational design of stable, supported metal catalysts for aqueous-phase processing: Insights from the hydrogenation of levulinic acid

Fischer–Tropsch synthesis over a 3D foamed MCF silica support: Toward a more open porous network of cobalt catalysts

Bio-propylene glycol by liquid phase hydrogenolysis of glycerol with Ni/SiO 2 -C catalysts

Contact Info

Product

Resources

About