Hydrogen generation from the dehydrogenation of ammonia-borane in the presence of ruthenium(III) acetylacetonate forming a homogeneous catalyst

Date

2013-01-01

Author

Duman, Sibel
Özkar, Saim

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

86
views

0
downloads

Starting with ruthenium(III) acetylacetonate a homogeneous catalyst is formed which catalyzes the release of 1 equivalent of hydrogen gas from the dehydrogenation of ammonia borane in toluene solution at low temperature in the range 50-65 degrees C. Mercury poisoning experiments showed that the catalytic dehydrogenation of ammonia-borane starting with ruthenium(III) acetylacetonate is a homogeneous catalysis. The final product obtained after the catalytic dehydrogenation of ammonia borane was thoroughly characterized by using B-11 Nuclear Magnetic Resonance and Infrared spectroscopies. The homogeneous catalyst formed from the reduction of ruthenium(III) acetylacetonate provides 950 turnovers (TTO) over 58 h and 27 (mol H-2)(mol Ru)(-1)(h)(-1) value of initial turnover frequency (TOF) in hydrogen generation from the dehydrogenation of ammonia-borane at 60 degrees C before deactivation. Kinetics of this homogenous catalytic dehydrogenation of ammonia-borane was studied depending on the catalyst concentration, substrate concentration, and temperature. The hydrogen generation was found to be first order with respect to both the substrate concentration and catalyst concentration. The activation parameters of this reaction were also determined from the evaluation of the kinetic data: activation energy; E-a = 48 +/- 2 kJ Mol(-1), the enthalpy of activation; Delta H-# = 45 +/- 2 kJ mol(-1) and the entropy of activation Delta S-# = -152 +/- 5 J mol(-1) K-1. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

URI

https://hdl.handle.net/11511/69908

Journal

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

DOI

https://doi.org/10.1016/j.ijhydene.2012.10.041

Collections

Department of Chemistry, Article

Suggestions

OpenMETU
Core

Hydrogen generation from hydrolysis of sodium borohydride using Ru(0) nanoclusters as catalyst Özkar, Saim (Elsevier BV, 2005-12-08) Sodium borohydride is stable in aqueous alkaline solution, however, it hydrolyses in water to hydrogen gas in the presence of suitable catalyst. By this way hydrogen can be generated safely for the fuel cells. Generating H-2 catalytically from NaBH4 solutions has many advantages: NaBH4 solutions are nonflammable, reaction products are environmentally benign, rate of H-2 generation is easily controlled, the reaction product NaBO2 can be recycled, H-2 can be generated even at low temperatures. All of the cata...
Hydrogen generation from the hydrolysis of sodium borohydride by using water dispersible, hydrogenphosphate-stabilized nickel(0) nanoclusters as catalyst Metin, Oender; Özkar, Saim (Elsevier BV, 2007-08-01) Water-dispersible nickel(0) nanoclusters are prepared from the reduction of nickel(II) acetylacetonate by sodium borchydride in aqueous solution and stabilized by hydrogerphosphate anion. Hydrogenphosphate-stabilized nickel(0) nanoclusters were characterized by using XPS, FT-IR, UV-Vis and NMR spectroscopic methods. As the first example of water-dispersible nickel(0) nanoclusters, they were employed as catalyst in the hydrolysis of sodium borohydride. Hydrogenphosphate-stabilized nickel(0) nanoclusters were...
Hydrogen gas production by electrohydrolysis of volatile fatty acid (VFA) containing dark fermentation effluent Tuna Öztürk, Eda; Argun, Hidayet (2009-01-01) Dark fermentation effluents of wheat powder (WP) solution containing different concentrations of volatile fatty acids (VFAs) were subjected to low voltage (1-3 V) DC current to produce hydrogen gas. Graphite and copper electrodes were tested and the copper electrode was found to be more effective due to higher electrical conductivity. The effects of solution pH (2-7), applied voltage (1-3 V) and the total VFA (TVFA) concentration (1-5 g L-1) on hydrogen gas production were investigated. Hydrogen production ...
Hydrogen production by using Rhodobacter capsulatus mutants with genetically modified electron transfer chains Ozturk, Yavuz; Yucel, Meral; Daldal, Fevzi; Mandaci, Sevnur; Gündüz, Ufuk; Turker, Lemi; Eroglu, Inci (2006-09-01) In Rhodobacter capsulatus excess reducing equivalents generated by organic acid oxidation is consumed to reduce protons into hydrogen by the activity of nitrogenase. Nitrogenase serves as a redox-balancing tool and is activated by the RegB/RegA global regulatory system during photosynthetic growth. The terminal cytochrome cbb3 oxidase and the redox state of the cyclic photosynthetic electron transfer chain serve redox signaling to the RegB/RegA regulatory systems in Rhodobacter. In this study, hydrogen prod...
Hydrogen sulfide determination by solid surface luminescence Eroglu, AE; Volkan, Mürvet; Bayramh, E; Ataman, Osman Yavuz; Mark, HB (1996-07-01) In the analytical system suggested, atmospheric hydrogen sulfide reacts with the surface of a filter paper treated with aqueous cadmium chloride and yields a luminescent species whose intensity can be correlated with the analyte concentration in ambient air. It was shown that the luminescent species are CdS solid particles which were formed in a well defined size. The paper luminescence was also tried on polymeric surfaces; polyethyleneoxide, polyvinyl alcohol, ethylcellulose and carboxymethylcellulose were...

Citation Formats

S. Duman and S. Özkar, “Hydrogen generation from the dehydrogenation of ammonia-borane in the presence of ruthenium(III) acetylacetonate forming a homogeneous catalyst,” INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, pp. 180–187, 2013, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/69908.