Hydrogen Generation in Water Splitting Reaction Using Aluminum: Effect of NaOH Concentration and Reaction Modelling Using SCM

The kinetics of the heterogeneous reaction of metal aluminum with water was studied in presence of NaOH as an activator for generating the hydrogen. Aluminum (Al) powder of average size of 100 µm and foil of thickness of 11 µm were utilized to study the effect of the shape of particles of aluminum on hydrogen generation. The hydrogen generation was reported at various concentrations of NaOH, ranging from 0.12 N to 0.67 N. The fractional conversion of Al was found to be 0.66 at 0.12 N and 1.0 at 0.185 N, 0.37 N, 0.54 N, 0.65 N NaOH concentration. The activation energy of the reaction has been determined at the stoichiometric concentration of 0.185 N NaOH at the temperature ranging from 298 to 323 K. An attempt was made to model the reaction using Shrinking Core Model (SCM) for determining the rate controlling mechanism for the heterogeneous reaction. The reaction was observed to follow the first order kinetics and the average value of reaction rate constant using Al power and foil was found to be 27.322 x 10-4 cm/min and 2.125 x 10-4 cm/min respectively.