TITLE:
Adsorption of Methylene Blue from Aqueous Solution Using Steam-Activated Carbon Produced from Lantana camara Stem
AUTHORS:
Omotayo Sarafadeen Amuda, Akeem Olusegun Olayiwola, Abass Olanrewaju Alade, Abolaji Grace Farombi, Segun Akanmu Adebisi
KEYWORDS:
Adsorption, Lantana camara, Methylene Blue, Steam Activation
JOURNAL NAME:
Journal of Environmental Protection,
Vol.5 No.13,
October
30,
2014
ABSTRACT: This study investigated
the adsorption of Methylene Blue (MB) present in wastewater onto the activated
carbon produce from Lantana camara stem. The agricultural material (Lantana
camara stem) was carbonized at 300°C for 2 h, ground and steam-activated. The Steam-Activated Lantana camara (SALC) stem carbon was characterized using Scanning Electron Microscope (SEM)
and Fourier Transform Infrared (FTIR) Spectrophotometry before and after
adsorption. Batch model experiments were conducted at 20°C to study the effects of pH, agitation time, adsorbent dosage and
initial concentration of methylene blue. The equilibrium adsorption isotherms
and kinetics were investigated. The FTIR bands at 3500, 2500, 2196 and 1682 cm-1 were shifted to 3646.3, 3030, 2822, 1709.05 cm-1 after MB
adsorption. Similarly, the Scanning Electron Microscopy (SEM) analysis showed
that the average pore size on the activated carbon was 20 μm. The Methylene Blue
(MB) uptake increased with the increase in pH. Similarly, the dye adsorption
increased as contact time increased, and reached equilibrium at 60 minutes. The
removal of the dye increased when the dosage was increased from 0.5 - 2.0 g·L-1, at
different dye concentrations (50 - 200 mg·L-1). The
percentage removal decreased with increasing initial dye concentration for
SALC. The adsorption isotherm data fitted well to the Freundlich isotherm (R2 = 0.989) while the experimental data fitted very well to the pseudo-second-order
kinetic model (R2 = 0.99). This study suggests that adsorbent
prepared from Lantana camara stem can be used effectively for the
adsorption of methylene blue in wastewater.