Heterogeneous Catalysis and Solid Catalysts

Deutschmann, Olaf; Knözinger, Helmut; Kochloefl, Karl; Turek, Thomas

doi:10.1002/14356007.a05_313.pub2

Cited by 95 publications

(123 citation statements)

References 407 publications

(387 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In this case, the support does not retain the crystallites strongly and they are able to agglomerate. However in the case where the adhesive forces between the support and crystallite are greater than the cohesive forces between crystallites, the crystallites become attached strongly over the support forming the socalled "pill-box" interaction where the crystallite wets the support 16,32 . This strong interaction might inhibit growth of these crystallites, especially by coalescence mechanism.…”

Section: Methodsmentioning

confidence: 99%

Sintering Behavior of TiO₂-Supported Model Cobalt Fischer–Tropsch Catalysts under H₂ Reducing Conditions and Elevated Temperature

Xaba

Villiers

2016

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

ABSTRACT:The sintering of model TiO2-supported cobalt catalysts has been studied. The TiO2 supports used were anatase, P25 (85% anatase-15% rutile) and rutile. The catalysts were characterized at each stage of treatment. These treatment stages were calcination, reduction and sintering. It was found that the TiO2 support does not influence the Co3O4 crystallite and particle size as shown by powder x-ray diffraction (XRD) and transmission electron microscopy (TEM) respectively. The reduction of the cobalt catalysts and bare supports was studied by temperature programmed reduction (TPR). It was found that the bare supports were not as inert as expected. The supports showed minor reduction as seen in the H2 consumption. All the cobalt catalysts showed a two-step reduction. Sintering of anatase-supported cobalt was shown to be the most substantial with P25-and rutile-supported showing a lower sintering tendency; P25-supported cobalt being the most stable based on TEM measurements. Sintering kinetics based on the Generalized Power law Expression (GPLE) model, showed that sintering of anatase-supported cobalt is the most rapid with a large sintering rate constant. Sintering of P25-supported cobalt is the lowest, shown by the lowest sintering rate constant. The study has conclusively shown the effect of the catalyst support phase. The study has also shown that the use of high surface area supports is not necessarily the only answer to preventing sintering. The phase of the catalyst support is also important.

show abstract

Section: Methodsmentioning

confidence: 99%

Sintering Behavior of TiO₂-Supported Model Cobalt Fischer–Tropsch Catalysts under H₂ Reducing Conditions and Elevated Temperature

Xaba

Villiers

2016

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

show abstract

“…The active carbon produced by reaction (2) was ab- sorbed by iron for carburizing. Therefore, the gaseous composition in the carburizing box completely depends on the equilibrium reaction (4) and (2). After the carbon content of iron at parts surface had once reached saturation, the gaseous composition in the carburizing box completely determines the reaction (4).…”

Section: Methodsmentioning

confidence: 99%

“…In 2009, Deutschmann et al [2], referred to 628 literatures, they worked together to publish a book <heterogeneous catalysis and solid catalyst>. They, in the author's opinion, comprehensively summarize the heterogeneous catalysis research and production results more than 100 years so far and many.…”

Section: Introductionmentioning

confidence: 99%

Study on the Mechanism of Heterogeneous Catalysis (1) —The Measurement of Equilibrium Pressure of Reaction BaCO<sub>3</sub> + C = BaO + 2CO, the Chemical States of Fe in Reaction Tank, and Chemical Reaction Model Catalytic Cycle Mechanism (CRMM)

Jin¹,

Bao²

2017

MSCE

View full text Add to dashboard Cite

The results on the equilibrium pressure measurement of BaCO 3 + C = BaO + 2CO reaction and the demonstration of chemical state of iron proved that decomposition-generation cycle of BaCO 3 and oxidation-reduction cycle of Fe in that reaction condition case were impossible to occur. The Chemical Reaction Model Catalytic Cycle Mechanism-CRMM does not exist at all for Ba-CO 3 , Fe, Noble metal catalysts. To call CRMM as a "principle" was obviously inappropriate. The TOF (Turnover Frequency-TOF: unit: s −1 ) was used to measure the activity size and life of catalyst, and it is clearly out of nothing.

show abstract

“…The physico-chemical properties (surface area, pore volume and particle size) of the catalyst have an important effect on the activity of the catalyst and consequently the product formation. Deutschmann et al [39] reported that large nonporous and porous catalyst particles tend to be more affected by mass transfer resistance when compared to powder or fine porous catalyst particles. Since cycloaddition of PO and CO 2 to produce PC is an exothermic reaction, a heterogeneous catalyst with small particles size, porosity, mechanical and thermal stability are important requirements to reduce and eliminate the effect of mass transfer resistance.…”

Section: Effect Of Mass Transfer In Heterogeneous Catalytic Processesmentioning

confidence: 99%

Greener synthesis of propylene carbonate using graphene-inorganic nanocomposite catalysts

Adeleye

Kellici

Heil³

et al. 2015

Catalysis Today

View full text Add to dashboard Cite

Heterogeneous Catalysis and Solid Catalysts

Cited by 95 publications

References 407 publications

Sintering Behavior of TiO₂-Supported Model Cobalt Fischer–Tropsch Catalysts under H₂ Reducing Conditions and Elevated Temperature

Sintering Behavior of TiO₂-Supported Model Cobalt Fischer–Tropsch Catalysts under H₂ Reducing Conditions and Elevated Temperature

Study on the Mechanism of Heterogeneous Catalysis (1) —The Measurement of Equilibrium Pressure of Reaction BaCO<sub>3</sub> + C = BaO + 2CO, the Chemical States of Fe in Reaction Tank, and Chemical Reaction Model Catalytic Cycle Mechanism (CRMM)

Greener synthesis of propylene carbonate using graphene-inorganic nanocomposite catalysts

Contact Info

Product

Resources

About

Heterogeneous Catalysis and Solid Catalysts

Cited by 95 publications

References 407 publications

Sintering Behavior of TiO2-Supported Model Cobalt Fischer–Tropsch Catalysts under H2 Reducing Conditions and Elevated Temperature

Sintering Behavior of TiO2-Supported Model Cobalt Fischer–Tropsch Catalysts under H2 Reducing Conditions and Elevated Temperature

Study on the Mechanism of Heterogeneous Catalysis (1) —The Measurement of Equilibrium Pressure of Reaction BaCO&lt;sub&gt;3&lt;/sub&gt; + C = BaO + 2CO, the Chemical States of Fe in Reaction Tank, and Chemical Reaction Model Catalytic Cycle Mechanism (CRMM)

Greener synthesis of propylene carbonate using graphene-inorganic nanocomposite catalysts

Contact Info

Product

Resources

About

Sintering Behavior of TiO₂-Supported Model Cobalt Fischer–Tropsch Catalysts under H₂ Reducing Conditions and Elevated Temperature

Sintering Behavior of TiO₂-Supported Model Cobalt Fischer–Tropsch Catalysts under H₂ Reducing Conditions and Elevated Temperature

Study on the Mechanism of Heterogeneous Catalysis (1) —The Measurement of Equilibrium Pressure of Reaction BaCO<sub>3</sub> + C = BaO + 2CO, the Chemical States of Fe in Reaction Tank, and Chemical Reaction Model Catalytic Cycle Mechanism (CRMM)