Hydrocracking continuous catalyst regeneration

The above work concentrated most of its attention on the use of zinc chloride as the molten halide and on the use of bituminous coal extract as feed to the process. Hydrocracking of the extract (1) and regeneration by a fluidized-bed combustion technique of the spent catalyst melt (2) from the process were both demonstrated in continuous bench-scale units. 

A new generation of so-called regenerative processes emerged with the development of multimetallic catalyst systems. They operate by continuous withdrawal and regeneration of the catalyst, which is then recycled to the reactors. This technology applies to the manufacture of gasoline and specifically to that of aromatics. This is because it can withstand more severe treatment conditions, which allow intensive cyclization of the paraffins, the removal of those that subsist by hydrocracking, and the hydrodealkylation of the heavier compounds,... 

The major part of these catal)dic processes is carried out in fixed bed reactors. Some of the main fixed bed catalytic processes are listed in Table 11.1-1. Except for the catalytic cracking of gasoil, which is carried out in a fluidized bed to enable the continuous regeneration of the catalyst, the main solid catalyzed processes of today s chemical and petroleum refining industries appear in this table. It should be added that there are also fluidized bed alternatives for phthalic anhydride and ethylene dichloride synthesis. Furthermore, Table 11.1-1 is limited to fixed bed processes with only one fluid phase trickle bed processes (e.g., encountered in the hydrotreatment and hydrocracking of heavier petroleum fractions) are not included in the present chapter. Finally, important processes... 

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