Catalyst support balls

Figure 5—9 illustrates one method to mitigate this problem. Baskets, partially filled with catalyst support balls, are inserted in the Claus plant catalyst bed. The depths of the baskets are sufficient to double the exposed surface area at the lop of the bed. While the effect on the initial reactor pressure drop is small, during the course of a one-year run, the average reduction in pressure drop was estimated to be 30%. The baskets shown in Figure 5-9 were only installed in the first reactor, as encrustation at the top of the second and third reactors is less of a problem. 

Distribution balls are frequently used on the top of each bed they are often employed to support the catalyst bed from below. The outlet of the reactor needs to include some type of collector in order to retain the catalyst and support balls while allowing the products to leave the reactor. 

Fumeaux, R. C., A. P. Davidson and M. D. Ball. 1987. Porous anodic aluminum oxide membrane catalyst support. European Patent Appl. 0,244,970A1. 

In this study it was demonstrated that with the aid of solventless ball-milling of catalyst components, dispersions of active components on carrier materials could be achieved, as measured by TPR, XPS and XANES, that are comparable to the dispersions achieved through conventional impregnation techniques of catalyst preparation. Comparable catalytic results are obtained by both preparation methods. Specifically, catalysts supported... 

The use of soluble polymers or dendrimers as chiral catalyst supports is another interesting way for catalyst separation [13]. Behaving like a homogeneous catalyst during the reaction, the catalyst can easily be separated by precipitation at the end of the reaction. High catalytic activities were reported using this approach. In addition, even use in membrane reactors may be possible using the ball-shaped dendrimers. 

Recently it has been observed that NCBs have been used as a support for heterogeneous catalyst due to its hollow core, mesoporous and ball-like structure. Park et al. [70] developed Pd(OAC)2 catalyst supported on NCBs and applied it for the synthesis of 2-substituted benzofuran from u-iodo phenol and various substituted terminal alkynes using Sonogashira cross-coupling reaction under copper and ligand-free condition. 

E.K. Yum, O.K. Yang, J.E. Kim, H.J. Park, Synthesis of 2-substituted benzofuran from o-iodophenol and terminal alkynes with a recyclable palladium catalyst supported on nano-sized carbon balls under copper- and ligand-free conditions. Bull. Korean Chem. Soc. 34 (2013) 2645-2649. 

The filler process has been used for the preparation of open porous glass carrier balls, such as Siran [452], and also to produce complex open porous glass and glassceramic carrier bodies [466]. They are used in biotechnology for storage, conduction and distribution of liquids and in filtration and separation processes and also as catalyst support material. 

There are other methods of preparation that iavolve estabhshing an active phase on a support phase, such as ion exchange, chemical reactions, vapor deposition, and diffusion coating (26). For example, of the two primary types of propylene polymerization catalysts containing titanium supported on a magnesium haUde, one is manufactured usiag wet-chemical methods (27) and the other is manufactured by ball milling the components (28). 

Industrial catalysts are usually composed of inorganic supports and metals on the supports. They are often prepared by heat treatment of metal ions on the support at high temperature sometimes under hydrogen. They have very complex structures. For example, they are the mixtures of metal particles with various sizes and shapes. Metal particles often strongly interact with the inorganic supports, thus resulting in the structure of half balls. 

On the basis of the detailed atomic-scale information provided by the STM images, a structural model of the CoMoS nanoclusters is proposed in which cobalt atoms have replaced molybdenum atoms along the sulfur edges of hexagonally truncated nanoclusters. As depicted in the ball model in Fig. 25(a) and (c), a tetrahedral environment of the cobalt atoms is produced if the outermost protrusions are assumed to be sulfur monomers, which agrees well with spectroscopic results reported for supported CoMoS catalysts (93,137-139 and previous DFT investigations (128,140. ... 

Figure 17.27. Catalyst packed adiabatic reactor, showing application of ceramic balls of graduated sizes for support at the bottom and hold-down at the top Rase, Chemical Reactor Design for Process Plants, Wiley, New York, 1977).

Reforming in the CRG process occurs adiabatically at 450-550 C at pressures up to about 600 psig (41 atmospheres). The reactor is a vertical cylindrical pressure vessel containing a bed of the special high-nickel catalyst which is supported on a grid or on inert ceramic halls. The gas flow is downwards through the bed and distributors are provided at inlet and outlet. A layer of ceramic balls on top of the bed prevents disturbance of the catalyst by the entering gas. 

The catalyst is often loaded on screens supported by a stainless steel grid near the bottom of the reactor. Often, large inert ceramic balls are loaded at the very bottom, with slightly smaller ceramic balls above the first layer, and then the catalyst. Smaller inert ceramic balls can also be loaded above the catalyst bed and topped off with the larger balls. The layer of inert balls can be 6 in to 2 ft in depth. The balls restrict the movement of the bed and distribute the liquid across the catalyst. 

Ball, S.C. et ah. The effect of dynamic and steady state voltage excursions on the stability of carbon supported Pt and PtCo catalysts, ECS Trans., 3, 595, 2006. 

J—housing g-support ring J—Inlet pipe connection dlKhars pipe connection 4—geTe —catalyst discharge pipe connection —porcelain balls ... 

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