Hydrogen membrane reactor system

P.N. Dyer, C.M. Chen, Engineering development of ceramic membrane reactor system for converting natural gas to H2 and syngas for liquid transportation fuel, Proceedings of the 2000 Hydrogen Program Review, DOE, 2000... 

Development of Ceramic Membrane Reactor Systems for Converting Natural Gas to Hydrogen and Synthesis Gas for Liquid Transportation Fuels, Proceedings of the 2002 U.S. DOE Hydrogen Program Review, NREL/CP-610-32405, Washington, D.C., 2002. 

The use of a membrane reactor for shifting equilibrium controlled dehydrogenation reactions results in increased conversion, lower reaction temperatures and fewer byproducts. Results will be presented on a palladium membrane reactor system for dehydrogenation of 1-butene to butadiene, with oxidation of permeating hydrogen to water on the permeation side. The heat released by the exothermic oxidation reaction is utilized for the endothermic dehydrogenation reaction. 

In the case of membrane reactor system, double tubular type reactor where Pd-Ag tube was used as inner tube of hydrogen permeable film, was used for the reactor of CH4 decomposition. Ar gas was fed to the inside of Pd-Ag tube at an atmospheric pressure for sweeping the permeated hydrogen. Gaseous mixture of CO2, H2, and N2 (CO2 H2 Nj = 1 4 3) was fed to the catalyst bed at W/F = 50g-cat-h/mol, where W and F stand for catalyst weight and flow rate, respectively. 

Three-phase catalytic membrane reactor systems, in our opinion, show significant promise, for near term application to hydrogenation reactions for fine chemicals synthesis. These reactions generally require mild operating conditions which will place less stringent requirements on the available and future commercial membranes. 

Light alkane (C2-C4) dehydrogenation was the reaction studied by Gryaznov and coworkers in their pioneering studies [2.1, 2.2]. In their dehydrogenation reaction studies, they used Pd or Pd-alloy dense membranes, which were 100 % selective towards hydrogen permeation. The choice of these membranes in many of the early studies is because they were commercially available at that time in a variety of compositions, and their metallic nature allows the construction of multitubular and other complex-shaped membrane reactor systems. Comprehensive review papers on Pd membrane reactors have been published by the same group [2.1, 2.2], and also by Shu et al [2.3]. 

M. M. Ermilova, N.V. Orekhova, and V.M. Gryaznov, in R. Bredesen, Ed., "Optimization of the Selective Hydrogenation Process by Membrane Catalysts", Proc. Fourth Workshop Optimisation of Catalytic Membrane Reactors Systems, Oslo, Norway, May, 1997, 187. 

Research, develop and demonstrate ion transport membrane (ITM) S mgas/ITM H2 ceramic membrane reactor system for the low-cost conversion of natural gas to hydrogen and s mthesis gas... 

M. Abdollahia, J. Yua, P. K. T. Liub, R. Ciorab, M. Ahimia, T. T. Tsotsis, Ultra-pure hydrogen production from reformate mixtures using a palladium membrane reactor system, J. Membr. Sci. 390-391 (2012) 32-A2. 

Zhang X et al (2006) Methanol steam reforming to hydrogen in a carbon membrane reactor system. Ind Eng Chem Res 45 7997-8001... 

Kragl and Wandrey made a comparison for the asymmetric reduction of acetophenone between oxazaborolidine and alcohol dehydrogenase.[59] The oxazaborolidine catalyst was bound to a soluble polystyrene [58] and used borane as the hydrogen donor. The carbonyl reductase was combined with formate dehydrogenase to recycle the cofactor NADH which acts as the hydrogen donor. Both systems were run for a number of residence times in a continuously operated membrane reactor and were directly comparable. With the chemical system, a space-time yield of 1400 g L"1 d"1 and an ee of 94% were reached whereas for the enzymatic system the space-time yield was 88 g L 1 d"1 with an ee of >99%. The catalyst half-life times were... 

Liese el al. attached a transfer-hydrogenation catalyst to a soluble polymer and applied this system in a continuously operated membrane reactor.[60] A Gao-Noyori catalyst was bound to a soluble polysiloxane polymer via a hydrosilylation reaction (Figure 4.41). 

Molten carbonate fuel cells Micro-electro-mechanical systems Microreactor Technology for Hydrogen and Electricity Micro-structured membranes for CO Clean-up Membrane reactor... 

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