Natural Celluloses as Catalysts in Dehydrogenation of NaBH4 in Methanol for H-2 Production


Can M., Demirci S., Sunol A. K. , Philippidis G., ŞAHİNER N.

ACS OMEGA, vol.5, no.25, pp.15519-15528, 2020 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 5 Issue: 25
  • Publication Date: 2020
  • Doi Number: 10.1021/acsomega.0c01653
  • Title of Journal : ACS OMEGA
  • Page Numbers: pp.15519-15528

Abstract

Cellulose, the most abundant renewable biopolymer, exists in many forms, such as microgranular cellulose (MGCell), sigmacell cellulose (SCell), cellulose fibers (FCell), and alpha-cellulose (AlfaCell). Several of these cellulose forms were protonated with an amine-containing agent polyethyleneimine (PEI), and the modified celluloses (XCell-PEI+) were studied as catalysts in methanolysis of NaBH4 for hydrogen (H-2) generation. It was found that the SCell-PEI+-catalyzed reaction is the fastest one among the modified celluloses with a hydrogen generation rate of 5520 +/- 119 mL H-2/(g of catalyst x min). The activation energies of MGCell-PEI+, SCell-PEI+, FCell-PEI+, and AlfaCell-PEI+ were determined as +21.7, +23.4, +24.8, and + 21.8 kJ/mol, respectively. Reusability of catalysts was investigated, and regeneration of cellulose based catalysts after the fifth cycle could be readily achieved by HCl treatment to completely recover its activity. Therefore, PEI-modified-protonated cellulose forms constitute sustainable, re-generable, and renewable catalysts for production of H-2, an environmentally benign green energy carrier.