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3.1 Introduction

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Catalysis plays a central role in chemical transformations and lies at the heart of countless chemical protocols, from academic research at laboratory level to the chemical industry level. By using catalytic reagents, one can reduce the temperature of a transformation, reduce reagent-based waste and enhance the selectivity of a reaction that potentially avoids the unwanted side reactions. Drivers for development of advanced catalysts include (i) production of high value products with inexpensive raw materials, (ii) energy efficient and environmentally benign chemical conversion processes, (iii) increasingly stringent environmental regulations, and (iv) low-cost catalysts such as with reduction or replacement of precious metals [1].

Catalysis occupies an important place in chemistry, where it develops in three directions, i.e., heterogeneous, homogeneous and enzymatic. Both the homogeneous and heterogeneous catalysis has its own merits and demerits due to which there is urgent need of a new catalytic system, which should be active like homogeneous catalysis, and should also be easily recoverable like heterogeneous catalyst. Considering the advantages of these two catalytic approaches, on the one hand heterogeneous catalysts are easy to recover but present some drawbacks, such as the drastic conditions they require to be efficient and mass transport problems; on the other hand, homogeneous catalysts are known for their higher activity and selectivity, but the separation of expensive transition metal catalysts from substrates and products remains a key issue for industrial applications.

Introducing a catalyst increases the speed of a reaction in one of three ways;

 It can lower the activation energy for the reaction,

 Act as a facilitator and bring the reactive species together more effectively, or

 Create a higher yield of one species when two or more products are formed.

Carbon Nanofibers

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