Preparation and Characterization of Activated Carbon from Root and Inflorescence of Enset/Ensete-Vetricosum/ for the Removal Pb(II) from Aqueous Solution

Abstract

Activated carbon was synthesized from the inflorescence and root of enset/ensete
vetricosum to effectively remove Pb(II) heavy metal ions from aqueous solutions. The
process involved chemical activation using H3PO4 followed by carbonization at 300°C
for 15 minutes. The most effective conditions for creating activated carbon varied
depending on the source material. For enset inflorescence (flower), a preparation
temperature of 25°C, a pH of 5, and a contact time of 60 minutes yielded the good
results. In contrast, the optimal conditions for preparing activated carbon from enset
root were a temperature of 30°C, a neutral pH of 7, and a shorter contact time of 30
minutes. Adsorbent doses of 1.5 g and 2 g in 200 mL solution were found to be
optimal. The adsorption capacities for Pb(II) by inflorescence and root were
determined to be 1.36 mg/g and 1.68 mg/g, respectively. Freundlich adsorption
isotherm models provided better fits for the experimental adsorption equilibrium data
compared to Langmuir models. FT-IR spectra analysis revealed the presence of
functional groups responsible for binding Pb(II) ions onto the adsorbent. Kinetics
data suggested that the pseudo-second order model best described the adsorption
process. The synthesized activated carbon showed high efficiency in removing Pb(II)
ions from aqueous solutions, making it a promising adsorbent for Pb(II) and related
heavy metal removal.