Ethylene glycol as an alternative solvent approach for very efficient hydrogen production from sodium borohydride with phosphoric acid and acetic acid catalysts

Abstract

For the first time, phosphoric acid (H3PO4) and acetic acid (CH3COOH) catalysts were used for efficient hydrogen (H-2) production from sodium borohydride (NaBH4) ethylene glycolysis reaction. In this experimental study, the effects of ethylene glycol/water ratio, ethylene glycol/acid ratio, NaBH4 concentration, acid concentration, and temperature were investigated. These ethylene glycol/water ratio experiments showed that the use of water alongside ethylene glycol negatively affects H-2 production. The hydrogen generation rate (HGR) values obtained for this ethylene glycolysis reaction with 1 M H3PO4 and 1 M CH3-COOH catalysts are 5800 and 4542 mLmin(-1), respectively. Also, the completion times of ethylene glycolysis reactions with these acids are 8 and 10 s, respectively. The n value obtained for ethylene glycolysis reactions according to the power-law kinetic model was 0.50. The activation energies obtained with H3PO4 (;)and CH3COOH catalysts were 24.45 kJ mol(-1) and 33.23 kJ mol(-1), respectively. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.