Slurry reactor novel catalytic

Slurry reactors find many applications in chemical industry. Most of these arc heterogeneous catalytic processes with hydrogenation of edible oils as the most classic example and SASOL s novel continuous Fischer Tropsch slurry synthesis process [1], the latest impressive new development in this area. Doraiswamy and Sharma [2] identified over 50 different slurry reactor applications, and an updated list would no doubt be longer still. 

Three phase systems have been the main focus of activities in chemical reaction engineering, and the many novel aspects of them are too numerous to cover here, hence only a few examples will be referenced. In the case of gas-1iquid-sparingly soluble solid, it has been demonstrated that particles substantially smaller than the diffusion film thickness of film model can enhance the specific rates of mass transfer if the reaction is sufficiently fast (45). Work in this area has been persistently pursued by Sada and coworkers (46,47). Recently Alper et al. (24) has pointed out and demonstrated that in catalytic slurry reactors similar enhancement can be observed if the catalyst particles are sufficiently small. There is however some dispute on the order of magnitude of the enhancement (48,49). Another aspect is complex reactions and in the case of slurry reactors the product distribution may well depend on the degree of diffusional resistance (50). Dynamic methods have been ingeniously employed to obtain physicochemical parameters in slurry reactors (51). 

Recently, a novel technology for three-phase processes has been developed the monolith catalyst, sometimes also called the frozen slurry reactor. Similar to catalytic gas-phase processes (Section 4.1), the active catalyst material and the catalyst carrier are flxed to the monolith structure. The gas and liquid flow through the monolith channels. The flow pattern in the vertical channels is iUustrated in Figure 6.14. At low gas velocities, a bubble flow dominates, and the bubble size distribution is even. At higher gas flow rates, larger... 

The EBR is one of the novel multiphase catalytic reactors which can be regarded as intermediate to slurry and fixed-bed operations. It is usually operated co-currently where the... 

Exelus has developed a novel structured catalytic system that allows one to meet all four criteria in a single catalytic system Hydrodynamic tests reveal that the HyperCat has similar gas hold-up as a slurry bubble column reactor but with a much lower liquid axial-dispersion coefficient. Cold-flow studies appear to indicate that the heat-transfer coefficient of this new system is similar to a bubble column reactor. Catalyst performance tests reveal that the performance of the HyperCat is similar to that of a powder catalyst when used in a plug-flow reactor. 

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