Solid state preparation and reaction kinetics for Co/B as a catalytic/acidic accelerator for NaBH4 hydrolysis

Abstract

In this study, the solid state synthesis and reaction kinetics for Co/B as a catalytic/acidic accelerator for sodium borohydride (NaBH4) hydrolysis were investigated. The Co/B a catalytic/acidic accelerator was synthesized from cobalt(II) chloride hexahydride (CoCI2·6H2O) and boron oxide (B2O3) by a procedure based on solid state synthesis. Differential thermal analyses (DTA) were performed on mixtures of CoCI2·6H2O and B2O3 at four different heating rates (5, 10, 15 and 20 °C min−1) in order to determine the solid state reaction temperatures. Kissinger and Doyle kinetic models were applied to the reaction kinetics data for the solid state preparation. The ideal temperature for the solid-state synthesis of Co/B catalytic/acidic accelerator was 196 °C. Additionally, the catalytic behavior of solid state synthesized Co/B as an catalytic/acidic accelerator for NaBH4 hydrolysis was investigated. The hydrolysis reactions were performed at temperatures of 22, 40, and 60 °C and the experimental data were fitted to zeroth, first, and second order kinetic models. The maximum hydrogen generation rate was 5,470 ml H2 min−1 g−1 cat and Ea was only 48.07 kJ mol−1.