ZeoliteBinderFaujasiteExtrudatesCatalysisShapingChemical interactions occurring between zeolites and alumina binders during the critical steps of catalyst forming are the focus of this study. Three widely used and commercially significant variants of FAU zeolite, covering a wide range of Si/Al ratios, ...
Since the pores in a particular zeolite are of a fixed size and shape, zeolite catalysts can work selectively on certain molecules, which is why they're sometimes referred to as shape-selective catalysts (they can select the molecules they work on in other ways beside shape and size, however...
Zeolites are tectosilicates with an impressive number of potential ways to link the corner shared SiO4tetrahedra forming a wide variety of pores and cavities31,32,33. Some of these framework tetrahedra are synthetically exchanged for other elements than Si4+, typically Al3+, but also Ga3+, B3+...
The highest 2-MN yield (40.6%) was achieved over the H-Mordenite catalyst at 350 °C with TOS = 15 min. It was found that the pore dimensions, catalysts acidity (BAS), and the thermodynamical stability of the product are the main parameters which influence the 2-MN yield. In our ...
Zeolites are three-dimensional aluminosilicates having unique properties from the size and connectivity of their sub-nanometer pores, the Si/Al ratio of the anionic framework, and the charge-balancing cations. The inhomogeneous distribution of the cations affects their catalytic performances because it ...
Chemical reactivity and sorption in zeolites are coupled to confinement and—to a lesser extent—to the acid strength of Brønsted acid sites (BAS). In presence of water the zeolite Brønsted acid sites eventually convert into hydronium ions. The gra
Moreover, coke formed by side-reactions can rapidly block the pores near the external surface, prematurely deactivating the zeolite catalyst [14], [15], [16], [17], [18], [19]. Hierarchical zeolites are materials in which wider pores within or between zeolite crystals are present. The ...
The selectoforming adds a shape selective effect of the zeolite cages to the hydrocracking by the choice of zeolites (erionite, offretite) which selectively convert only C 5 to C 9 n-paraffins from naphthas and reformates.(3) Oil dewaxing also uses a shape selective catalyst for the ...
The degree of covalency in the ligand–metal bond has far-reaching implications towards reactivity and catalysis as it is the key to activate directional long-range electron transfer pathways58,59, enhance catalyst stability60 and determine the selective stabilization of intermediate species in redox ...
Increased yields of middle distillate and jet fuel and increased catalyst activity are obtained in a hydrocracking process by the use of a catalyst containing a beta zeolite and a Y