Homogeneous Catalyst Recovery and Recycle with Co2
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چکیده
Catalytic synthesis can be achieved by using either homogeneous or heterogeneous organometallic complexes, or homogeneous enzymatic biocatalysts. However, each of these methods offers advantages and disadvantages that must be balanced cautiously. Homogeneously catalyzed reactions are highly efficient in terms of selectivity (i.e. regioselectivity, enantiomeric excesses) and reaction rates, due to their monomolecular nature. Unfortunately, catalyst recovery can be very difficult (due to the homogeneous nature of the solution) and product contamination by residual catalyst or metal species is a problem. In contrast, heterogeneously catalyzed reactions allow easy and efficient separation of high value products from the catalyst and metal derivatives. However, selectivity and rates are often limited by the multiphasic nature of this system and/or variations in active site distribution from the catalyst preparation.
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