Process Integration and Cascade Catalysis

They involve fewer unit operations, less solvent and reactor volume, shorter cycle times, higher volumetric and space-time yields and less waste (lower E 

Higher volumetric and space-time yields Less waste/lower E factor 

Catalyst recycle complicated Complicated reaction mixtures and work-up 

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Special attention is given to the integration of biocatalysis with chemocatalysis, i.e., the combined use of enzymatic with homogeneous and/or heterogeneous catalysis in cascade conversions. The complementary strength of these forms of catalysis offers novel opportunities for multi-step conversions in concert for the production of speciality chemicals and food ingredients. In particular, multi-catalytic process options for the conversion of renewable feedstock into chemicals will be discussed on the basis of several carbohydrate cascade processes that are beneficial for the environment. 

Full exploitation of cascade conversions by the true integration of biocatalytic and chemocatalytic procedures requires merging human s chemistry with nature s reaction conditions the latter impose a much stricter constraint with respect to reaction temperature, pressure and medium (Fig. 13.16). Consequently, a renaissance in the field of synthetic organic chemistry and catalysis is necessary to develop novel conversion processes that meet biocatalytic conditions. 

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