Hydrogen Generation via Tris(acetylacetonato)cobalt(III) as aHeterogeneous Nano Catalyst; Kinetics Study

Hydrogen is a promising alternative energy source to conventional fuels, including fossil fuel.Several methods were reported for the generation of hydrogen but hydrolysis of aqueous sodiumborohydride (NaBH۴) solutions is One of the non-fossil methods to generate hydrogen. NaBH۴with high gravimetric hydrogen capacity of about ۱۰.۸ wt.%. is promising as a hydrogen storagematerial. This work reports the experimental results on synthesis and using Co(acac)۳ catalyst,Tris(acetylacetonato)cobalt(ІІІ) for hydrolysis of NaBH۴. The synthesized Co(acac)۳ catalyst wascharacterized by XRD, FESEM, TEM, XPS, and FT-IR techniques. The morphological andstructural properties of the obtained materials were examined by FESEM and TEM images,Particle distribution histogram shows that the average particles size are ۲۰ nm. The catalyticactivity of catalysts was tested in the hydrolysis reaction of NaBH۴ in a semi-batch system. Thevolume of the evolved hydrogen gas was determined by a water displacement method. The effectsof catalyst amount, NaBH۴ concentration and solution temperature on the hydrogen generationrate were investigated and partial order respect to NaBH۴ concentration and catalyst are ۰.۶۵۸۴and ۰.۶۰۳۶, respectively. Arrhenius equation was used to calculate Ea of hydrogen generationreaction at different temperatures. The activation energy, ۲۰.۸۵ (KJ/mol) is calculated forhydrolysis of NaBH۴ which is a very promising amount

Keywords:

Tris(acetylacetonato)cobalt(ІІІ) , Hydrogen generation , Sodium borohydrides , Nanocatalyst , Kinetics.