Abstract
The efficiency of as-synthesized and calcined mesoporous silica, using clay as a silica source, to remove the reactive blue BF-5G dye was investigated. The materials were characterized by X-ray diffraction (XRD) analysis, energy-dispersive X-ray fluorescence (ED-XRF), and Fourier-transform infrared spectroscopy. The kinetic and adsorption isotherms were also studied. The XRD and ED-XRF results showed that the Chocolate clay is rich in SiO2 (69.4%) and has a large amount of other oxides, which can be eliminated by acid leaching. According to the characterization results, the MCM-41 synthesis was effective and produced a highly-ordered material. The kinetic study showed the adsorption corresponded predominantly to the pseudo-second order model. Adsorption equilibrium was reached after 3 h, and the data were better fitted to the Freundlich model. Furthermore, both samples obtained satisfactory removal results, being potential adsorbents having reduced cost due to the use of an alternative silica source.
Keywords:
dye removal; MCM-41; adsorption; Chocolate clay; reactive blue BF-5G
