Hydrolytic Cleavage Of Ammonia-Borane Complex For Hydrogen Production

A new process for generating hydrogen via near room temperature hydrolysis of AB complex using small amounts of platinum group metal catalyst has been studied. Using in situ 11B NMR spectroscopy, the overall rate of K2Cl6Pt catalyzed hydrolysis of AB complex was calculated to be third-order. The pre-exponential factor (A) and the activation energy (Ea) of Arrhenius equation, ln k = ln A - Ea/RT, were determined to be: A = 1.6 × 1011 L mol-1 s-1 and Ea = 86.6 kJ mol-1 for temperature range of (25-35 °C). X-ray photoelectron spectroscopy of the residue suggested that the platinum salt was reduced from Pt4+ to Pt0 within the course of the reaction and X-ray diffraction analysis pattern for the residue showed crystallized single-phase boric acid. © 2007