scholarly journals A green and efficient process for the synthesis of Benzothiazinones using Phosphate fertilizers MAP, DAP and TSP as heterogeneous catalysts

2019 ◽  
pp. 349-354
Author(s):  
IMANE BAHAMMOU ◽  
BADR MALEK ◽  
TOURYA GHAILANE ◽  
RACHIDA GHAILANE ◽  
SAID BOUKHRIS ◽  
...  
Keyword(s):  
Heterogeneous Catalysts ◽  
Phosphate Fertilizers ◽  
Efficient Process

Synthesis of 9-Arylhexahydroacridine-1,8-diones Using Phosphate Fertilizers as Heterogeneous Catalysts

2019 ◽  
Vol 55 (9) ◽  
pp. 1380-1386
Author(s):  
S. Chehab ◽  
Y. Merroun ◽  
T. Ghailane ◽  
R. Ghailane ◽  
S. Boukhris ◽  
...  
Keyword(s):  
Heterogeneous Catalysts ◽  
Phosphate Fertilizers

scholarly journals Direct use of mineral fertilizers MAP, DAP, and TSP as heterogeneous catalysts in organic reactions

2016 ◽  
Vol 5 (6) ◽  
pp. 615-623 ◽  
Author(s):  
Imane Bahammou ◽  
Ayoub Esaady ◽  
Said Boukhris ◽  
Rachida Ghailane ◽  
Nouzha Habbadi ◽  
...  
Keyword(s):  
Heterogeneous Catalysts ◽  
Knoevenagel Condensation ◽  
Aromatic Aldehydes ◽  
Significant Loss ◽  
Mineral Fertilizers ◽  
Phosphate Fertilizers ◽  
Reaction Conditions ◽  
Catalytic Activities ◽  
First Time ◽  
Direct Use

In this paper, we reported the first use of phosphate fertilizers (MAP, DAP, and TSP) as heterogeneous catalysts for organic reactions.  Their catalytic activities were investigated in the first time in Knoevenagel condensation of various aromatic aldehydes with malononitrile at room temperature.  These minerals phosphate showed high catalytic activities and ability to be recovering and reusing without a significant loss in their catalytic activities.  In order to reach the optimal reaction conditions for Knoevenagel condensation, we carried out a kinetic study of the effect of reaction time, the effect of solvent, the amount of catalysts and the variation of the range of the particles size the more active.  The best conditions were obtained by the use of these fertilizers (MAP, DAP, and TSP) in their commercial status, simply crashed in powder, without any purification, using ethanol as solvent.  These phosphate fertilizers prove to be very promising and effective heterogeneous catalysts for the condensation of Knoevenagel.

SYNTHESIS OF 9-ARYLHEXAHYDROACRIDINE-1,8-DIONES USING PHOSPHATE FERTILIZERS AS HETEROGENEOUS CATALYSTS

2019 ◽  
Vol 55 (9) ◽  
pp. 1473
Author(s):  
S. CHEHAB ◽  
◽  
Y. MERROUN ◽  
T. GHAILANE ◽  
R. GHAILANE ◽  
...  
Keyword(s):  
Heterogeneous Catalysts ◽  
Phosphate Fertilizers

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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