Heterogeneous catalysis, green chemistry

Ask the average man on the street for an example of catalysis, and you will most likely hear about the thing on the exhaust pipe that reduces engine emissions . As we shall see, the remarkable story of the catalytic converter is not only an excellent example of catalysis, but also highlights the connection between heterogeneous catalysis, green chemistry, and sustainable development. 

This chapter outlines the principles of green chemistry, and explains the connection between catalysis and sustainable development. It covers the concepts of environmental impact, atom economy, and life-cycle analysis, with hands-on examples. Then it introduces the reader to heterogeneous catalysis, homogeneous catalysis, and biocatalysis, explaining what catalysis is and why it is important. The last two sections give an overview of the tools used in catalysis research, and a list of recommended books on specialized subjects in catalysis. 

Keywords Oxidation, green chemistry, heterogeneous, catalysis, hydrogen peroxide... 

B. K. Min, C. M. Friend, Heterogeneous gold based catalysis for green chemistry Low-temperature CO oxidation and propene oxidation, Chem. Rev. 107 (2007) 2709. 

Microwave irradiation has been successfully applied in chemistry since 1975 and many examples in organic synthesis have been described [3, 4], Several reviews have been published on the application of this technique to solvent-free reactions [5], cycloaddition reactions [6], synthesis of radioisotopes [7], fullerene chemistry [8] and advanced materials [9], polymers [10], heterocyclic chemistry [11], carbohydrates [12], homogeneous [13] and heterogeneous catalysis [14], medicinal and combinatorial chemistry [15], and green chemistry [16]. All these applications are described elsewhere in this book. 

Heterogeneous catalysis, in particular, addresses the goals of green chemistry by providing the ease of separation of product and catalyst, thereby eliminating the need for separation through distillation or extraction. In addition, environmentally benign catalysts such as clays and zeolites, may replace more hazardous catalysts currently in use. 

O2 and H2 are completely miscible with scCOi. This reduces multi-phase reaction problems Heterogeneous catalysis for green chemistry processes... 

While TS-1 is an ideal candidate for epoxidation of small linear alkenes with hydrogen peroxide, it has been reported to be less successful for large bulkier alkenes. This has been attributed to size/diffusion limitations associated with its microporous structure. Despite this limitation, the development of TS-1 assisted in the creation of a new type of solid, recyclable catalyst called a redox molecular sieve and subsequently enabled selective organic oxidation reactions to encompass many principles of green chemistry via heterogeneous catalysis. 

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