Lead removal from water by modified activated carbon produced from banana stem

Abstract

Banana stem-activated carbon (BSAC) and modified banana stem-activated carbon, containing sulfur, nitrogen, and oxygen-containing groups derived from banana stem, were prepared and studied for Pb(II) ion removal. The materials were characterized by scanning electron microscopy, X-Ray diffraction, surface area analysis, and Fourier transform infrared spectroscopy. SEM images showed that the materials are porous, and XRD confirmed that the structures are amorphous and resemble the graphitic hexagonal structure of carbon materials. Surface areas of these materials ranged from 517.67 m2/g for the bare banana stem activated carbon to 234.03, 453.74, 252.97, and 22.96 m2/g for sulfur, oxygen, sulfur and oxygen and imino-thiobiuret modified activated carbon. For the adsorption, sulfur-containing functional groups banana stem activated carbon (S-BSAC) was used as the adsorbent for lead removal. The optimized condition were 100 mg/L of lead(II) ions, 2 h of contact time, pH at 6, and 0.8 mg of adsorbent dosage. The analysis was done by inductively coupled plasma optical emission spectroscopy. The removal efficiency was as high as 99.78% for Pb(II) at 100 mg/L and could be used for 3 cycles.