борогидриды

The study of the anodic oxidation of borohydride-ion BH− 4 on catalytically active nickel electrode by methods of potentiostatic inclusion, galvanostatically inclusion, cyclic voltammetry and infrared spectroscopy with Fourier transformation. The composition of some intermediates of the process of electrochemical oxidation of BH− 4 and the mechanism of decomposition of borohydride, which includes the following basic stages: BH− 4 → BH3(OH)− → BH2(OH)− 2 → BH(OH)− 3 → B(OH)− 4 , is determined.

A study of the solubility in the ternary systems NaBH₄–NaOH–H₂O, KBH₄–KOH–H₂O, NaOH–NaBO₂–H₂O и KOH–KBO₂–H₂O is of special fundamental and practical interest. The first two systems are used as a fuel and as a hydrogen source in hydrogen power engineering that includes the low-temperature fuel cells; borohydrides are converted into metaborates. Hence, the last two systems represent the discharged by-product.

The paper studies the influence of temperature (50–100°C) and alkalinity (C OH – = 2.33–9.53 M) of aqueous solutions on the hydrolysis (self-destruction) kinetics of borohydride ions BH₄^– Characteristic peculiarities of the kinetic curve have been established and formulae to approximate the temperature-concentration dependence of the hydrolysis rate are proposed.