Hydrogen generation from

H2 serves as the alternative energy source relative to fossil fuels and biomass [181] because it is clean and environmentally friendly. Hence, catalytic hydrogen generation from water under mild conditions is one of the goals for the organometallic catalysis. One of the hopeful methods is the electrochemical reduction of protons by a hydrogenase mimic. 

Transition-metal catalyzed photochemical reactions for hydrogen generation from water have recently been investigated in detail. The reaction system is composed of three major components such as a photosensitizer (PS), a water reduction catalyst (WRC), and a sacrificial reagent (SR). Although noble-metal complexes as WRC have been used [214—230], examples for iron complexes are quite rare. It is well known that a hydride as well as a dihydrogen (or dihydride) complex plays important roles in this reaction. 

Scheme 67 The proposed mechanism for iron-catalyzed light-driven hydrogen generation from water...

Tien HT, Chen JW (1989) Hydrogen generation from artificial sea water in a semiconductor septum electrochemical photovoltaic cell. Photochem Photobiol 49 527-530... 

In addition to the use of hydrogen directly, hydrogen generated from CO and water (water-gas shift reaction) is also very effective in hydrogenating activated alkenes under basic conditions (Eq. 10.3).5... 

Schucan T., Hydrogen generation from stand-alone wind-powered electrolysis systems, in Case Studies of Integrated Hydrogen Energy Systems, Final Report of the IEA Task 11 Integrated Systems, 129-145, Switzerland, 1998, Chapter 9. 

Bak, T., Nowotny, Rekas, M., and Sorrell, C.C., Photo-electrochemical hydrogen generation from water using solar energy. Materials-related aspects, bit.. Hydrogen Energ., 27,991, 2002. 

Efficient Hydrogen Generation from Organic Chemical Hydrides with... 

Catalytic Hydrogen Generation from Organic Chemical Hydrides under Superheated Liquid-Film Conditions by Use of Laboratory-Scale Continuous Reactor... 

To realize efficient hydrogen generation from organic chemical hydrides with the superheated liquid-film-type catalysis in a continuous operation, catalytic dehydrogenation by use of a continuous reactor was investigated on a laboratory scale [13,14]. 

Time courses of rate of hydrogen generated from decalin with carbon-supported platinum catalyst at various feed rates in bench-scale continuous operation. Catalyst platinum nanoparticles supported on ACC (5 wt-metal%), 0.29 g (one layer, ), 0.58 g (two layers, A), and 0.87 g (three layers, O). Feed rate of decalin 1.5, 2.0, 2.5, 3.0, and 5.0 mL/min. Reaction conditions boiling and refluxing by heating at 280°C and cooling at 25°C. 

Improving the Kinetics for Hydrogen Generation from P-Type Semiconductors... 

Iceland may start with methanol powered PEM vehicles and vessels. The University of Iceland is involved in research on the production of methanol (CH3OH) from hydrogen combined with carbon monoxide (CO) or C02 from the exhaust of aluminum and ferrosilicon smelters. This would capture hundreds of thousands of tons of CO and C02 released from these smelters. If this is combined with hydrogen generated from electrolysis using renewable power, Iceland could cut its greenhouse gas emissions in half. 

The catalytic aqueous phase reforming might prove useful for the generation of hydrogen-rich gas from carbohydrates extracted from renewable biomass and biomass waste streams. The biomass-derived hydrocarbons are suitable to hydrogen generation from biomass, as well as for the reforming. 

Fig. 2 Apparatus for hydrogenation with hydrogen generated from sodium boro-hydride.

CATALYTIC HYDROGENATION WITH HYDROGEN GENERATED FROM SODIUM BOROHYDRIDE 4 ... 

---