CATALYTIC HYDROGEN GENERATION FROM SODIUM BOROHYDRIDE USING ACTIVATED PISTACHIO SHELL BIOMASS

Abstract

In this study, hydrogen production, one of the renewable energy types with high energy efficiency, using pistachio shell (PS) from organic wastes with no economic value, was investigated. Hydrogen can be produced from many sources. However, hydrogen production from sodium borohydride is one of the preferred efficient methods due to its easy transport and storage. In the scope of the study, PS-KOH-ZnCl2 catalyst synthesised using PS was used for H2 generation in methanolysis reactions of NaBH4. To synthesise the most active catalyst, experiments were carried out using various chemicals (CH3COOH, KOH, ZnCl2) as support materials, chemicals' different molarity values (1, 3, 5, 7 M) and per cent values (10, 20, 30, 40 %), different carbonisation temperatures (400, 500, 600, 700 degrees C) and times (30, 45, 60, 75 minutes) as catalyst production process parameters. The most active catalyst determined as a result of these investigations was synthesised by mixing PS with 3M KOH and 30% ZnCl2 and carbonising at 500 degrees C for 60 minutes. Then, using this catalyst, tests were performed at various NaBH4 quantities, different catalyst amounts and various temperatures to measure the impact of the experimental parameters on H2 generation. As a result of the experiments, the highest hydrogen generation rate (HGR) was recorded as 10917 mL min-1g-1. Additionally, the activation energy (Ea) of PS-KOH-ZnCl2 was computed as 11.3 kJ/mol. According to the data obtained from the study, it was concluded that waste pistachio shells can be utilized efficiently in the generation of a versatile type of energy such as hydrogen.