Characterization of Musa Paradisiaca Activated Carbon Supporting Iron Nanoparticles, after Adsorption of Hydrogen Sulphide (H2S) from Biogas on a Fixed Bed Column

Abstract

In this study, the characteristics of Musa Paradisiaca (MP) iron-funtionalysed activated carbon (AC) after adsorption of H2S from biogas were demonstrated. The AC was chemically impregnated with potassium hydroxide (KOH) and then carbonised at a temperature of 500°C for 3 hours for activation. The activated carbon was then functionalized with iron oxide (Fe2O3) and labelled BANK-Fe. The H2S adsorption test was performed on a fixed bed column. The biogas flow rate was 1 L.min− 1. with 25% water (w/w) added. This test resulted in an adsorption capacity of 9.86 mgH2S.g-1 after a saturation time of 615 minutes. This was satisfactory for the purposes of biogas treatment. The present work is a follow-up to the adsorption tests already carried out. The analyses on the functionalized activated carbon sample after adsorption underwent a physical and chemical change. The surface morphology was modified: the more or less homogeneous asperities of the BANK-Fe (before adsorption) gave way to a relatively more amorphous form. Sulphur elements were detected in the sample after adsorption, in contrast to the starting sample. This confirms the adsorption of H2S from the biogas. Oxygen and Iron in BANK-Fe decreased by 39.49% and 94.16% respectively in atomic concentration, which proves that they reacted and played a role in the H2S adsorption mechanism. In addition, the microporosity decreased by 35.71%: the iodine value decreased from 1065.96 mg.g− 1 to 685.26 mg.g-1. This indicates that part of the pores, in particular the micropores, was occupied by the pollutants during the adsorption of the biogas.