SURFACTANT ASSISTED SILICA- GRAPHENE COMPOSITE AS EFFECTIVE ADSORBENT AGAINST METHYLENE BLUE DYE

Abstract

Surfactant based composites have good capability for elimination of colored pollutants from industrial waste water. In this study, two different Silica-Graphene (SG) and Surfactant assisted Silica-Graphene (SSG) composites was prepared by sol-gel technique and used as adsorbents for the removal of methylene blue (MB) dye from aqueous solution. The adsorption properties of prepared composite materials were characterized by Scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray phase diffraction and Raman spectroscopy. The adsorbent characteristic property of the composites was studied using UV-Vis spectrophotometer and zeta potential measurements. Batch adsorption experiments were carried out to study the effect of percentage removal versus contact time on dye adsorption properties at different pH. The developed colloidal silica-graphene was porous structure with a size > 200 nm is uniformly distributed and significantly enhances adsorption capacity. The isotherm analysis indicated that the adsorption data can be represented by Langmuir isotherm model. Surface charge of developed composite was assessed by Zeta potential measurement result showed negative charge -28.3mV at all pH value. The results show that the electrostatic interaction between cationic dyes and the negative surface of composite has a great effect on adsorption capacity.