scholarly journals Increasing use of synthetic zeolites as heterogeneous catalysts in various traditional and emerging catalytic processes to drive market growth

2022 ◽  
Vol 2022 (1) ◽  
pp. 2
Keyword(s):  
Heterogeneous Catalysts ◽  
Market Growth ◽  
Synthetic Zeolites ◽  
Catalytic Processes

scholarly journals Things go better with coke: the beneficial role of carbonaceous deposits in heterogeneous catalysis

2016 ◽  
Vol 6 (2) ◽  
pp. 363-378 ◽  
Author(s):  
C. H. Collett ◽  
J. McGregor
Keyword(s):  
Heterogeneous Catalysis ◽  
Heterogeneous Catalysts ◽  
Catalyst Deactivation ◽  
Catalytic Performance ◽  
Fischer Tropsch ◽  
Carbonaceous Deposits ◽  
Beneficial Role ◽  
Catalytic Processes

Carbonaceous deposits on heterogeneous catalysts are traditionally associated with catalyst deactivation. However, they can play a beneficial role in many catalytic processes, e.g. dehydrogenation, hydrogenation, alkylation, isomerisation, Fischer–Tropsch, MTO etc. This review highlights the role and mechanism by which coke deposits can enhance catalytic performance.

ChemInform Abstract: Heterogeneous Catalysts and Catalytic Processes

ChemInform ◽  
2010 ◽  
Vol 23 (27) ◽  
pp. no-no
Author(s):  
H. KNOEZINGER
Keyword(s):  
Heterogeneous Catalysts ◽  
Catalytic Processes

ChemInform Abstract: Simulation of Heterogeneous Catalysts and Catalytic Processes Using the Density Functional Method

ChemInform ◽  
2011 ◽  
Vol 42 (12) ◽  
pp. no-no
Author(s):  
V. A. Nasluzov ◽  
E. A. Ivanova-Shor ◽  
A. M. Shor ◽  
I. V. Yudanov ◽  
N. Roesch
Keyword(s):  
Density Functional ◽  
Heterogeneous Catalysts ◽  
Density Functional Method ◽  
Functional Method ◽  
Catalytic Processes

Simulation of heterogeneous catalysts and catalytic processes using the density functional method

2010 ◽  
Vol 51 (6) ◽  
pp. 832-842 ◽  
Author(s):  
V. A. Nasluzov ◽  
E. A. Ivanova-Shor ◽  
A. M. Shor ◽  
I. V. Yudanov ◽  
N. Rösch
Keyword(s):  
Density Functional ◽  
Heterogeneous Catalysts ◽  
Density Functional Method ◽  
Functional Method ◽  
Catalytic Processes

Production of Biodiesel Via Catalytic Processes: A Brief Review

2018 ◽  
Vol 16 (5) ◽  
Author(s):  
Eugênia Leandro Almeida ◽  
Cid Marcos Gonçalves Andrade ◽  
Onélia Andreo dos Santos
Keyword(s):  
Heterogeneous Catalysts ◽  
Raw Materials ◽  
Enzymatic Catalysis ◽  
Combustion Process ◽  
Fats And Oils ◽  
Diesel Oil ◽  
Animal Fats ◽  
Environmental Damages ◽  
Catalytic Processes ◽  
Materials Used

Abstract Currently, there is a worldwide concern, not only with the exhaustion of diesel oil, but also with the environmental damages caused by this fuel, from the process of extracting oil to consumption. The emission of the gases from the combustion process of this fuel are harmful to the health of living beings and contribute directly to the worsening of the greenhouse effect. Biodiesel appears in this context as a possible substitute for diesel. Thus, the main objective of this work was to carry out a bibliographical review of the main catalytic processes available in the literature for the production of biodiesel, respectively, the main chemical reactions involved in these processes, being: the esterification and transesterification reaction. Among the catalytic processes, the alkaline, acid and enzymatic catalysis was highlighted. And, among the main raw materials used in the production process are: vegetable oils, animal fats and oils and fats; as economically and environmentally viable alternatives. Still referring to the raw materials, there are the alcohols: methanol and ethanol, which are frequently used. In this way, the most varied catalytic methods present in the literature were presented. For each catalytic process, the work was presented, which developed methodologies for: homogeneous, heterogeneous catalysts, dispersed or immobilized, with the most diverse raw materials, which are currently used or that may be used in the process of obtaining biodiesel in the future. Industrial scale.

What catalysis needs from the electron microscopist

1988 ◽  
Vol 46 ◽  
pp. 694-695
Author(s):  
Alexis T. Bell
Keyword(s):  
Active Sites ◽  
Heterogeneous Catalysts ◽  
Catalyst Deactivation ◽  
Surface Composition ◽  
Internal Surface ◽  
Active Phase ◽  
Atomic Scale ◽  
Metal Catalyst ◽  
Internal Surface Area ◽  
Porous Support

Heterogeneous catalysts, used in industry for the production of fuels and chemicals, are microporous solids characterized by a high internal surface area. The catalyticly active sites may occur at the surface of the bulk solid or of small crystallites deposited on a porous support. An example of the former case would be a zeolite, and of the latter, a supported metal catalyst. Since the activity and selectivity of a catalyst are known to be a function of surface composition and structure, it is highly desirable to characterize catalyst surfaces with atomic scale resolution. Where the active phase is dispersed on a support, it is also important to know the dispersion of the deposited phase, as well as its structural and compositional uniformity, the latter characteristics being particularly important in the case of multicomponent catalysts. Knowledge of the pore size and shape is also important, since these can influence the transport of reactants and products through a catalyst and the dynamics of catalyst deactivation.

Electron holography of catalysts

1995 ◽  
Vol 53 ◽  
pp. 416-417
Author(s):  
A. K. Datye ◽  
D. S. Kalakkad ◽  
L. F. Allard ◽  
E. Völkl
Keyword(s):  
Heterogeneous Catalysts ◽  
High Surface ◽  
High Surface Area ◽  
Atomic Scale ◽  
Nano Particles ◽  
Phase Image ◽  
Electron Holography ◽  
Specimen Thickness ◽  
Phase Information ◽  
Particle Structure

The active phase in heterogeneous catalysts consists of nanometer-sized metal or oxide particles dispersed within the tortuous pore structure of a high surface area matrix. Such catalysts are extensively used for controlling emissions from automobile exhausts or in industrial processes such as the refining of crude oil to produce gasoline. The morphology of these nano-particles is of great interest to catalytic chemists since it affects the activity and selectivity for a class of reactions known as structure-sensitive reactions. In this paper, we describe some of the challenges in the study of heterogeneous catalysts, and provide examples of how electron holography can help in extracting details of particle structure and morphology on an atomic scale.Conventional high-resolution TEM imaging methods permit the image intensity to be recorded, but the phase information in the complex image wave is lost. However, it is the phase information which is sensitive at the atomic scale to changes in specimen thickness and composition, and thus analysis of the phase image can yield important information on morphological details at the nanometer level.

Quantitative nano-characterization of heterogeneous catalysts

1995 ◽  
Vol 53 ◽  
pp. 398-399
Author(s):  
P.A. Crozier ◽  
M. Pan
Keyword(s):  
Heterogeneous Catalysts ◽  
Low Dose ◽  
Imaging Techniques ◽  
Structural Features ◽  
Catalyst Characterization ◽  
New Developments ◽  
Double Phase ◽  
Phase Systems ◽  
Dose Imaging

Heterogeneous catalysts can be of varying complexity ranging from single or double phase systems to complicated mixtures of metals and oxides with additives to help promote chemical reactions, extend the life of the catalysts, prevent poisoning etc. Although catalysis occurs on the surface of most systems, detailed descriptions of the microstructure and chemistry of catalysts can be helpful for developing an understanding of the mechanism by which a catalyst facilitates a reaction. Recent years have seen continued development and improvement of various TEM, STEM and AEM techniques for yielding information on the structure and chemistry of catalysts on the nanometer scale. Here we review some quantitative approaches to catalyst characterization that have resulted from new developments in instrumentation.HREM has been used to examine structural features of catalysts often by employing profile imaging techniques to study atomic details on the surface. Digital recording techniques employing slow-scan CCD cameras have facilitated the use of low-dose imaging in zeolite structure analysis and electron crystallography. Fig. la shows a low-dose image from SSZ-33 zeolite revealing the presence of a stacking fault.

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