Hydrogen production from sodium borohydride for fuel cells in presence of electrical field

Abstract

SUMMARYSodium borohydride (NaBH 4 ) reacts with water to produce 4 mol of hydrogen per mol of compound at room temperature. Under certain conditions, it was found that 6 mol of hydrogen per mol of sodium borohydride was produced in the presence of electrical field created by DC voltages, whereas 4 mol of hydrogen was produced in the presence of catalyst per mole of sodium borohydride. Electrical field created by alternative current with three different waves (sin, square and triangle type) increases the hydrolysis of sodium borohydride. It was found that hydrogen produced from sodium borohydride by applying an electrical field can be effectively used for both increasing the electrolysis of water and hydrolysis of sodium borohydride. The hydrolysis reaction was carried out at temperature of 20, 30, 40 and 601C in the presence of electrical field created by AC voltages square wave. The experimental data were fitted to the kinetic models of zero-order, first-order and nth-order. The results indicate that the first-order and nth-order model give a reasonable description of the hydrogen generation rate at the temperature higher than 301C. Reaction rate constant at different temperatures were determined from experimental data, and activation energy was found to be 50.20 and 52.28 kJ mol À1for first-order and nth-order, respectively.

Hydrogen generation from hydrolysis of sodium borohydride with a novel palladium metal complex catalyst

“…The hydrogen generation experiment was performed in a 200 mL three-neck flask immersed in a water bath, which was described in details along with its experimental setup in our previous work [42]. The catalytic activity of the Pd complex catalyst was determined by recording the volume of hydrogen that was generated by the hydrolysis of 10 mL NaBH 4 including 5 wt% NaBH 4 .…”

Hydrogen generation from catalytic hydrolysis of sodium borohydride by a novel Co(II)–Cu(II) based complex catalyst

“…Hydrogen generation tests of NaBH 4 hydrolysis with the prepared complex catalysts were carried out in a 200 mL threeneck flask immersed in a water bath, which was described in details along with its experimental setup in our previous work [38]. The prepared Co(II)eCu(II) catalyst was initially put at the bottom of the flask at a nitrogen atmosphere system.…”

Electroless Nickel-Based Catalyst for Diffusion Limited Hydrogen Generation through Hydrolysis of Borohydride

“…In order to prevent the spontaneous generation of hydrogen from NaBH 4 solutions, alkaline solutions are prepared and, thus, allowed solutions to be stored safely until use [7,12]. A catalyst is needed to promote hydrogen generation from these alkaline solutions.…”

“…A catalyst is needed to promote hydrogen generation from these alkaline solutions. Another advantage NaBH 4 has over NH 3 BH 3 is that the NaBO 2 by-product can be recycled to synthesize NaBH 4 [12][13][14]. Metal catalysts have been shown to be effective promoters for hydrogen generation from the hydrolysis of NaBH 4 .…”