Highly active hydrogen generation from sodium borohydride methanolysis and ethylene glycolysis reactions using protonated chitosan-zeolite hybrid metal-free particles

Abstract

Herein, the synthesis of low-cost, non-toxic and recyclable protonated chitosan-zeolite hybrid metal-free catalysts was carried out. The metal-free hybrid catalysts were used for the first time for efficient H2 production from NaBH4 methanolysis and ethylene glycolysis. The prepared chitosan-zeolite-H composite was characterized by Xray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-Ray analyser (EDS), Fourier-transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), Brunauer-EmmettTeller (BET) and X-ray photoelectron spectroscopy (XPS) analyses. The different chitosan/zeolite ratios and different calcination temperatures, the effect of temperature and NaBH4 amount and reusability parameters were investigated. Also, the possible mechanism of H2 formation in methanol and ethylene glycol with chitosanzeolite-H is discussed. HGR values of NaBH4 (0.25 g) methanolysis and ethylene glycolysis were 17,500 and 10,428 ml min- 1g- 1, respectively. Ea values obtained for the NaBH4 methanolysis and ethylene glycolysis were found to be 37.29 kJ mol-1 and 50.00 kJ mol-1, respectively.