Partial hydrogenation of alkynes has industrial and academic relevance on a large scale; industries such as petrochemical, pharmacological and agrochemical use these compounds as raw material. Finding an economic, active and selective catalyst for the production of alkenes through partial hydrogenation of alkynes is thus an important challenge. Mono- and bimetallic catalysts (palladium, ruthenium and nickel) were synthetized by the incipient wetness technique using gamma alumina and an activated carbon as supports. The catalysts were characterized by inductively coupled plasma, hydrogen chemisorption, temperature-programmed reduction and X-ray photoelectronic spectroscopy (XPS). The objective of this work is to study 1-heptyne-selective hydrogenation using supported catalysts influenced by different factors: (a) pretreatment reduction temperature, (b) reaction temperature, (c) type of support, (d) metal loading, (e) precursor salt and (f) addition of a second metal to monometallic palladium catalyst. The Lindlar commercial catalyst, commonly used in these types of reactions, was used for comparative purposes. XPS technique allowed verifying that the presence of electron-deficient species on the catalyst surface with high metal loading affects the conversion and selectivity to the desired product. Nevertheless, the influence of geometrical effects and/or mixed active sites in the catalysts, as well as metal-metal and metal-support interactions, cannot be neglected.

Hydrogen is one of the abundant elements on earth majorly in the form of water (H2O) and mainly as hydrogen gas (H2). Catalytic hydrogenation is a key reaction that has versatile applications in different industries. The main objective of this book is to bring together various applications of hydrogenation through the perspective of leading researchers in the field. This book is intended to be used as a graduate-level text book or as a practical guide for industrial engineers.

The collection of contributions in this volume presents the most up-to-date findings in catalytic hydrogenation. The individual chapters have been written by 36 top specialists each of whom has achieved a remarkable depth of coverage when dealing with his particular topic. In addition to detailed treatment of the most recent problems connected with catalytic hydrogenations, the book also contains a number of previously unpublished results obtained either by the authors themselves or within the organizations to which they are affiliated.Because of its topical and original character, the book provides a wealth of information which will be invaluable not only to researchers and technicians dealing with hydrogenation, but also to all those concerned with homogeneous and heterogeneous catalysis, organic technology, petrochemistry and chemical engineering.

Selective hydrogenation of olefins is an important process in both chemical and pharmaceutical industries. This chapter reviews intriguing catalytic studies accomplished by employing a variety of catalysts such as metal complexes, supported materials, supported metal complexes, and nanosized materials for polyene hydrogenation. In addition, new research area involving unsupported colloidal nanoparticle catalysts, which exhibit an excellent activity and selectivity toward the polyene hydrogenation is introduced. The high activity of colloidal metal nanoparticle catalysts often allows the reactions to be completed under mild conditions, at atmospheric pressure, and room temperature. These colloidal nanoparticle catalysts also offer an advantage of facile separation and multiple recycling without significant losses in activity and selectivity. This chapter provides important fundamental understandings on the influence of chemical environments (solvents, ligands, dopants, etc.) and compositions (metal complex, metals, alloys, etc.) toward the catalytic activity and selectivity of various catalysts in homogeneous, heterogeneous, and semi-heterogeneous conditions. The systematic evaluation discussed in this chapter would pave a way to further develop chemo-, regio-, and stereo-selective catalysts for polyene hydrogenation.