Page 187 - Design of Simple and Robust Process Plants
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172  Chapter 5 Process Simplification and Intensification Techniques

                   Hydrogen           Oxygen


                  Hydrogenation       Oxidation



                                                Water
                  Regeneration        Extraction


                         Working fluid  Finishing
                          Aqueous
                          solution
                                      Hydrogen
                                      peroxide
                 Fig. 5.25. Production of hydrogen peroxide by anthraquinone
                 process (Ref. Turunen, with permission of BHR publ.).











                         Working fluid
                          Oxygen








                 Fig. 5.26. Tubular reactor for oxidation (Ref. Turunen, with
                 permission of BHR publ.).



                   .  Packed columns are another option used when the catalyst is in pellet form,
                      and gas and liquid flow are either co-current or counter-currently operated.
                The hydrogenation reactions are both rapid and strongly exothermic, and are limited
                 by mass transfer in conventional reactors.
                   Different options were experienced to intensify the reactors, although it should be
                 realized that a very wide range of hydrogenation applications exist, from the selec-
                 tive hydrogenation of acetylenes in hydrocarbon streams to the total hydrogenation
                 of nitro-aromatic compounds and many others. Here, the discussion is limited to
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