Batch reactors catalytic cracking

Cascade control, 395-402, 410, 445 Catalytic reactors auctioneering control, 405-7 fluid catalytic cracking, 75-76 regeneration of catalyst, 406 Centra] processing unit, 553-54 Characteristic equation, 285-87 of digital control loop, 623, 628 Characteristic polynomial, 145, 167, 321 of second-order system, 188 Chemical reactors batch (see Batch reactor) catalytic (see Catalytic reactor)... 

We also note that the process of decay in catalytic cracking has been amply demonstrated(l)(2)(3) to be a function of the time of exposure of the catalyst to the reactants i.e. of the time on stream. Such time-dependent behaviour indicates that the kinetics of the process of catalyst decay are the same as those to be expected in a batch reaction. On reflection, it is obvious that the situation of the catalyst charge in a steady-state reactor is in fact that of a batch of reactant (the catalyst) undergoing a chemical process (catalyst decay) as a function of the time on stream i.e. the time it spends at reaction conditions - at reaction temperature and in the presence of an atmosphere of feed, products and potential poisons. 

Figure 3.6 Conversions obtained in the catalytic cracking of a model polyolefin mixture (semi-batch reactor, P/C = 50 T = 400°C, t = 30 min) [43]. (Reproduced by permission of the American Chemical Society)...

Due to similar catalytic results obtained in n-hexane cracking in the flow and batch reactor in dependence on the nature of carrier gas, the same mechanism should work. 

The use of solid acids has been traditionally biased towards large-scale continuous vapour phase processes such as catalytic cracking and paraffin isomerisations. However, it is increasingly recognised that there is also a great need for solid acid catalysts which are effective in liquid-phase organic reactions such as those employed in many batch-type reactors by fine, speciality and pharmaceutical intermediate chemical manufacturers. This has contributed towards a substantial recent research effort into the development of new solid acid catalysts.86-91... 

Figure 5.13 Conversion and product distribution obtained in PP catalytic cracking at 400 °C in a batch reactor over ZSM-5, MCM-41, and amorphous silica-alumina ...

As stated above for catalytic cracking simulation under the reaction conditions of FCCs a bench scale internal recycle batch reactor was proposed by de Lasa (1991, 1992). It has to be pointed out that this objective is not easy nor straight forward considering the complex fluid-dynamic... 

The Riser Simulator Reactor is an internal recycle fluidized batch reactor. This patented novel device (de Lasa 1989 de Lasa, 1991), has been developed and successfully tested for the estimation of kinetic parameters of catalytic cracking of heavy oils (Kraemer and de Lasa, 1988). The details of the unit are given in the section entitled "Novel Techniques For FCC Catalyst Selection and Kinetic Modelling" by de Lasa and Kraemer in this NATO-ASI Proceedings. 

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