Conversion of 2-octanol over nickel-alumina, cobalt-alumina, and alumina catalysts

Sivaraj, C; Srinivasan, Ram; Milburn, Diane R.; Davis, Burtron H.

doi:10.1016/s1381-1169(97)00018-6

Cited by 66 publications

(39 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As can be seen, the pattern of IM1 has relatively high diffraction intensities of the cubic spinel phase such as Co 3 O 4 and/or CoAl 2 O 4 and γ-Al 2 O 3 phase. [4][5][6] The IM2 sample has the same spinel diffraction pattern as IM1, but with much lower intensities, and no γ-Al 2 O 3 phase can be detected. The XRD peak breadth for the SG sample is even broader, which reveals a nanosized crystalline state in this sample.…”

Section: Resultsmentioning

confidence: 99%

“…It is difficult to establish the chemical and structural phases for the three samples based on XRD characteristics alone because Co 3 O 4 and CoAl 2 O 4 both have cubic spinel structure with almost identical diffraction peak positions. [4][5][6] Nonetheless, the difficulty in resolving these two phases can be overcome by FTIR and XPS techniques. Figure 2 shows the FTIR spectra of the three as-prepared catalysts.…”

Section: Resultsmentioning

confidence: 99%

“…From the fundamental viewpoint, these interactions depend primarily upon factors such as the concentration of metal species, nature of the support, and temperature and duration of calcination, which in turn depends on the actual material selection and preparation method. 4,6,7 Surface active phases, for example, can be significantly differentiated via various preparative routes, even keeping the overall chemical composition constant for a catalyst.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Metal−Support Interactions in Co/Al₂O₃ Catalysts: A Comparative Study on Reactivity of Support

2000

View full text Add to dashboard Cite

Co/Al 2 O 3 catalysts have been prepared with conventional impregnation and sol-gel methods to vary the chemical reactivity of the alumina support. The material system has been investigated with X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), diffuse reflectance Fourier transform spectroscopy (DRIFT), Brunauer-Emmett-Teller (BET) method, X-ray photoelectron spectroscopy (XPS), temperatureprogrammed reduction (TPR) (with thermogravimetric analysis (TGA) and differential thermal analysis (DTA)), and gas chromotography (GC) for the catalytic oxidation of CO. It had been found that the reactivity of the support changes the surface structure and chemical composition of catalysts significantly. When the metalsupport interaction is weak, Co 3 O 4 is a predominant surface phase (which is interfaced by a "cobalt surface phase"). With an increase in support reactivity, CoO and CoAl 2 O 4 are found to be present on the surface. The cobalt content on the surface decreases upon the increase in support reactivity and surface area. At the high atomic ratio of Al/Co, there are more dAlsOsH bonds that show higher basicity. Reducibility of the phases observed decreases on the order of Co 3 O 4 , CoO, and CoAl 2 O 4 . It is found that the removal of CO on metallic sites is much easier in the catalyst with lower metal-support interactions. At room temperature, reactions between the adsorbed CO and lattice oxygen have been observed in all samples. The catalytic activity for the CO combustion reaction increases with the decrease in metal-support interactions of the catalysts. Possible causes for the above observations have been addressed.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Metal−Support Interactions in Co/Al₂O₃ Catalysts: A Comparative Study on Reactivity of Support

2000

View full text Add to dashboard Cite

show abstract

“…It can be seen that the catalysts prepared in this investigation have much larger specific surface areas than the results reported previously for the Ni/Al 2 O 3 catalysts obtained by other precursors via the sol-gel process (SA 200-300 m 2 /g) 2,15 or by the co-precipitation method (SA 110-200 m 2 /g) 3,16 at the same calcination temperature (500 • C). Even higher Table 3.…”

Section: Bet Surface Area Resultsmentioning

confidence: 43%

The use of alumatrane for the preparation of high‐surface‐area nickel aluminate and its activity for CO oxidation

Utchariyajit

Gülari

Wongkasemjit

2005

Applied Organom Chemis

View full text Add to dashboard Cite

Supported nickel has been used in a wide range of applications for industrial reactions, such as steam reforming, hydrogenation and methanation. In this work, nickel aluminate was prepared by the sol-gel process using alumatrane as the alkoxide precursor, directly synthesized from the reaction of inexpensive and available compounds, aluminum hydroxide and TIS (triisopropanolamine) via the oxide one pot synthesis (OOPS) process. Various conditions of the sol-gel process, such as pH, calcination temperature, hydrolysis ratio and ratio of nickel to aluminum, were studied. All samples were characterized using FTIR, TGA, XRD, TPR, DR-UV and BET. The BET surface area was in the range of 340-450 m 2 /g at the calcination temperature of 500 • C with a mesoporous pore size distribution. Catalyst activity testing in CO oxidation reaction depended on Ni : Al ratio and calcination temperature. Higher activity was obtained from higher Ni content and lower calcination temperature. In addition, catalysts prepared using alumatrane precursor had higher percentage conversion than those prepared using aluminum hydroxide precursor.

show abstract

“…The impressive optical properties of CoAl 2 O 4 , its catalytic properties and its potential as an effective humidity sensor makes it particularly interesting to consider it as a nanopigment (Cavalcante et al 2009;Salavati-Niasara et al 2009), as a catalyst (Chokkaram et al 1997;Chemlal et al 2000;Nga and Chi 2005) and as a sensor (Sirotyuk et al 1998). Sirotyuk and coworkers considered CoAl 2 O 4 , MgAl 2 O 4 and ZrAl 2 O 4 spinels as humidity sensors and have found that the CoAl 2 O 4 spinel had the highest sensitivity [Sirotyuk et al (1998)].…”

Section: Introductionmentioning

confidence: 99%

Preparation and Characterization of Cobalt Aluminate Spinels CoAl₂O₄ Doped with Magnesium Oxide

Azer

Ramadan

Ghaly

et al. 2012

Adsorption Science & Technology

View full text Add to dashboard Cite

Cobalt aluminate spinels were prepared from cobalt and aluminium nitrate solutions using sol-gel synthesis route by ammonium hydroxide precipitation. The gels were dried at 75°C, doped with different amounts of magnesium nitrate, and then calcined for 3 h at 650°C. Sample characterization was carried out by infrared spectroscopy, X-ray diffraction, scanning electron microscopy, nitrogen adsorption studies, thermogravimetry and by determining acid-base properties. This was carried out with the objective of elucidating the effect, if any, of the presence of the dopant on the spinel structure and properties. The spinel structure was clearly exhibited in all of the prepared samples which were predominantly mesoporous. None of the samples showed any acidic properties, i.e. they exhibited only basic properties. We found that doping with Mg resulted in a slightly increased disorder of cation distribution for those samples doped with higher amounts of Mg. Doping also led to a general increase in surface areas and the development of larger pores, as well as larger content of chemisorbed water.

show abstract

Conversion of 2-octanol over nickel-alumina, cobalt-alumina, and alumina catalysts

Cited by 66 publications

References 23 publications

Metal−Support Interactions in Co/Al₂O₃ Catalysts: A Comparative Study on Reactivity of Support

Metal−Support Interactions in Co/Al₂O₃ Catalysts: A Comparative Study on Reactivity of Support

The use of alumatrane for the preparation of high‐surface‐area nickel aluminate and its activity for CO oxidation

Preparation and Characterization of Cobalt Aluminate Spinels CoAl₂O₄ Doped with Magnesium Oxide

Contact Info

Product

Resources

About

Conversion of 2-octanol over nickel-alumina, cobalt-alumina, and alumina catalysts

Cited by 66 publications

References 23 publications

Metal−Support Interactions in Co/Al2O3 Catalysts: A Comparative Study on Reactivity of Support

Metal−Support Interactions in Co/Al2O3 Catalysts: A Comparative Study on Reactivity of Support

The use of alumatrane for the preparation of high‐surface‐area nickel aluminate and its activity for CO oxidation

Preparation and Characterization of Cobalt Aluminate Spinels CoAl2O4 Doped with Magnesium Oxide

Contact Info

Product

Resources

About

Metal−Support Interactions in Co/Al₂O₃ Catalysts: A Comparative Study on Reactivity of Support

Metal−Support Interactions in Co/Al₂O₃ Catalysts: A Comparative Study on Reactivity of Support

Preparation and Characterization of Cobalt Aluminate Spinels CoAl₂O₄ Doped with Magnesium Oxide