Hydrodesulfurization process schemes

In summary, protection of the catalyst and the reactor is essential if shutdowns are to be minimized, and this is particularly the case when the heavier feedstocks are used in the hydrodesulfurization process. Some measure of protection from the asphaltic constituents can be achieved by removal of these materials by means of a deasphalting step (Chapter 7). The overall relative merits of any particular total processing scheme should be assessed in terms of feedstock properties, product yields, process variables, and last but not least, process economics. 

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