Cobalt loaded organic acid modified kaolin clay for the enhanced catalytic activity of hydrogen release via hydrolysis of sodium borohydride

Abstract

Inorganic acids such as hydrochloric acid (HCl), nitric acid (HNO3) and sulphuric acid (H2SO4) are generally used in the acid modification of clays. Here, CoB catalyst was synthesized on the acetic acid-activated kaolin support material (CH3COOH -kaolin- CoB) with an alternative approach. This prepared catalyst, firstly, was used to catalyze the hydrolysis of NaBH4 (NaBH4-HR). The structure of the raw kaolin, kaolin-CH3COOH, and CH3COOH-kaolin-CoB samples were characterized by X-ray diffraction spectroscopy (XRD), Fourier transforms infrared spectroscopy (FTIR), scanning electron microscope (SEM), and nitrogen adsorption. At the same time, this catalyst performance was examined by Co loading, NaBH4 concentration, NaOH concentration, temperature and reusability parameters. The end times of this hydrolysis reaction using raw kaolin-CoB and CH3COOH-kaolin-CoB were found to be approximately 140 and 245 min, respectively. The maximum hydrogen generation rates (HGRs) obtained at temperatures 30 degrees C and 50 degrees C were 1533 and 3400 mL/min/g(catalyst), respectively. At the same time, the activation energy was found to be 49.41 kJ/mol. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.