Natural Celluloses as Catalysts in Dehydrogenation of NaBH4 in Methanol for H2 Production

Mehmet Can; Sahin Demirci; Aydin K Sunol; George Philippidis; Nurettin Sahiner

doi:10.1021/acsomega.0c01653

Natural Celluloses as Catalysts in Dehydrogenation of NaBH₄ in Methanol for H₂ Production

ACS Omega. 2020 Jun 15;5(25):15519-15528. doi: 10.1021/acsomega.0c01653. eCollection 2020 Jun 30.

Authors

Mehmet Can¹, Sahin Demirci¹, Aydin K Sunol², George Philippidis³, Nurettin Sahiner^{1

2

4}

Affiliations

¹ Department of Chemistry & Nanoscience and Technology Research and Application Center, Canakkale Onsekiz Mart University Terzioglu Campus, 17100 Canakkale, Turkey.
² Department of Chemical and Biomedical Engineering, University of South Florida, Tampa, Florida 33620, United States.
³ Patel College of Global Sustainability, University of South Florida, 4202 E. Fowler Avenue, CGS101, Tampa, Florida 33620, United States.
⁴ Department of Ophthalmology, Morsani College of Medicine, University of South Florida, 12901 Bruce B Downs B. Downs Blv., MDC 21, Tampa, Florida 33612, United States.

Abstract

Cellulose, the most abundant renewable biopolymer, exists in many forms, such as microgranular cellulose (MGCell), sigmacell cellulose (SCell), cellulose fibers (FCell), and α-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 (H₂) 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 H₂/(g of catalyst × 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 H₂, an environmentally benign green energy carrier.