The aim and originality of our current study are to use the original biomass (activated carbon) obtained by functionalizing waste banana peels (commonly found in Turkey) with acid in NaBH4 methanolysis and to examine its contribution to the hydrogen generation rate (HGR). Our study consisted of three stages. In the first stage, the optimum conditions were determined by examining the catalyst under parameters such as different acid types, different carbonization temperatures, and different carbonization times. Thus, based on the maximum HGR value, the optimum conditions were determined as H3PO4, 600 °C, and 40 min. In the second step, the effects of parameters such as acid concentration, NaBH4 concentration, catalyst amount, and temperature on HGR were investigated. As a result of methanolysis experiments (condition: catalyst amount: 100 mg, acid amount: 30%, NaBH4 concentration: 2.5%, temperature: 30 °C, carbonization temperature: 400 °C, and carbonization time: 40 min.), the maximum HGR value, the reaction completion time and activation energy were found as 65,625 mLmin− 1gcat−1, 0.233 min, and 4.56 kJ/mol, respectively. It was observed that the obtained activation energy was lower than that of some catalysts available in the literature. In addition, the structural and morphological examination of the banana peel (catalyst) with high HGR and low activation energy revealed that the acid functionalization process was successfully carried out.

    Abstract
    1 Introduction
        1.1 Experimental part
    2 Results and discussion
        2.1 Part I
        2.2 FTIR characterization
        2.3 XRD characterization
        2.4 SEM and EDX characterization
        2.5 BET characterization
        2.6 Part II
        2.7 Determination of the most suitable acid type
        2.8 Determination of the concentration of H3PO4
        2.9 Determination of the most suitable carbonization temperature
        2.10 Determination of the most suitable carbonization time
        2.11 Part III
        2.12 Effect of the concentration of NaBH4
        2.13 Effect of the amount of catalyst (banana peel)
        2.14 Effect of the temperature
        2.15 Reusability of catalyst (banana peel)
    3 Conclusion
    Acknowledgements 
    References

• Duygu Elma Karakaş(Science and Technology Application and Research Center)
• Mustafa Kaya(Department of Chemical Engineering, Siirt University)
• Sabit Horoz(Department of Metallurgy and Materials Engineering, Sivas University of Science and Technology)