Synthesis and Application of LGB/St/Al2O3 Biocomposite for Sensitive Detection and Efficient Removal of Brilliant Green Dye from Wastewater

Biosorbent has excellent properties for the removal of dyes from wastewater but the leaching of its components in acidic and alkaline medium is a problem which necessitates preparing stable composite to overcome the leaching process. This paper focused on the synthesis of a novel biocomposite (LGB/St/Al3O3) by coupling between lignin of guava stem, stearic acid and alumina. LGB/St/Al(3)O(3)was characterized using ultra violet/ visible/infrared spectra, scanning electron microscope, x-ray diffraction and thermal analysis. The LGB/St/Al3O3 was tested for removing of the brilliant green dye (Br.G) from wastewater; the various parameters like Br.G concentration, pH, temperature and shaking time were studied to optimize the best condition for removing of Br.G from aqueous solution. It was found that Br.G was removed 100% in pH range 3-9 with shaking 5 min at room temperature. The pseudo-second order model best described the kinetics for removal of Br.G (R-2 = 0.999) with initial rate constant 0.1 mmol/g min. The equilibrium process is well described by the Freundlich isotherm model (R-2 = 0.978), which attributed to the heterogeneous surface of LGB/St/Al3O3. Value of Delta G was -2.0 kJ mol(-1), this indicate the spontaneous nature of the removal process. The method exhibited a detection limit of 2.7-6.7 mu g/L in wastewater samples with RSD of 1.2-3.2% (n = 5). It is indicate that LGB/St/Al3O3 would find important application for removal of basic dyes from wastewater, owing to the advantages of high efficiency, low cost and environmental friendliness.