Boric acid versus boron trioxide as catalysts for green energy source H2 production from sodium borohydride methanolysis

Here, boric acid (H 3 BO 3 ) and its dewatered form, boron trioxide (B 2 O 3 ) were tested as catalysts for hydrogen (H 2 ) evolution in the methanolysis of sodium borohydride (NaBH 4 ) in methanol. Parameters such as catalyst types and their amounts, NaBH 4  concentration, and the reaction temperature affecting the hydrogen generation rate (HGR) were studied. It has been found that H 3 BO 3  and B 2 O 3  catalyzed methanolysis reaction of NaBH 4  follow up first-order kinetics relative to the concentration of NaBH 4 . Furthermore, the conversion and activity of these catalysts were examined to determine their performance in ten consecutive use. Interestingly, H 3 BO 3  and B 2 O 3  have demonstrated superior catalytic performances in methanolysis of NaBH 4  comparing to the studies published in literature with the activation energy of respectively 22.08 kJ.mol -1 , and 23.30 kJ.mol -1  in H 2  production. The HGR was calculated as 6481 mL.min -1 .g -1  and 5163 mL.min -1 .g -1  for H 3 BO 3  and B 2 O 3  catalyst, respectively for 50 mg catalyst at 298 K. These results are comparably better than most metal nanoparticle catalysts used for H 2  production in addition to the naturally occurring boron-based environmentally friendliness of these materials.