Seite - 91 - in Advanced Chemical Kinetics

Chapter 6 Catalyst Kinetics and Stability in Homogeneous Alcohol Acceptorless Dehydrogenation Martin Nielsen Additional information is available at the end of the chapter http://dx.doi.org/10.5772/intechopen.70654 Provisional chapter © 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. DOI: 10.5772/intechopen.70654 Catalyst Kinetics and Stability in Homogeneous Alcohol Acceptorless Dehydrogenation Martin  Nielsen Additional information is available at the end of the chapter Abstract The anthropogenic climate changes caused by meeting the energy demands of society by use of fossil fuels render the development of benign alternatives imperative. Probably, the most promising alternative is generating energy by means of power units driven by, e.g., solar, wind, water, etc., and then storing the energy that is not immediately used in battery type devices. Such a device might consist of hydrogen chemically stored as alcohol(s). The advantage of this method is that it allows gaseous hydrogen to be stored much more efficiently when liquefied as an alcohol. Moreover, as will be shown in this review, it is possible to release the hydrogen under mild conditions when employing homogeneous catalysis. This review considers the kinetic aspects of homogeneously catalysed acceptorless alcohol dehydrogenation reactions. For clarity, the sections are divided according to alcohol substrate, and each metal are described and discussed in subsections. Moreover, the kinetic information in the homogeneously catalysed AAD is traditionally provided simply as the turnover frequency, and more in-depth studies on the actual kinetic parameters are to date still largely elusive. Keywords: homogeneous catalysis, acceptorless dehydrogenation, alcohols, catalyst kinetics, catalyst stability 1. Introduction Acceptorless alcohol dehydrogenation (AAD) is the extrusion of H2 from alcohols resulting in H2 and carbonyl products. The latter includes, e.g., aldehydes, ketones, esters, amides, car- boxylic acids, and CO2. Conducting AAD by means of homogeneous catalysis is a promis- ing approach towards a viable applicable energy carrier technology. For example, the vision with “Methanol economy” [1] is that H2 produced by renewable energy sources is stored and transported in MeOH. The reasons for doing so are that H2 is unfeasible to transport and that © 2018 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.