REMOVAL OF MALACHITE GREEN OXALATE DYE FROM AQUEOUS SOLUTIONS USING BARK OF POLYALTHIA LONGIFOLIA AS A BIOSORBENT: ADSORPTION AND KINETIC STUDIES

摘要

In this study, removal of the basic dye Malachite Green oxalate from aqueous solution through adsorption was investigated using bark powder of Polyalthia longifolia (False Ashoka) as the biosorbent. Batch sorption experiments were carried out at 34℃ with variation in adsorbate concentration, particle size of adsorbent, agitation time and pH of the solution. Equilibrium isotherms were investigated by Langmuir and Freundlich adsorption isotherms. In the present investigation, Langmuir isotherm fitted well with experimental data and monolayer adsorption capacity was found to be 10 mg/g at pH 5.07 and 30℃ with good correlation coefficient (R~2=0.998). Pseudo first order plots and pseudo second order plots have been analyzed at different concentrations for kinetic study. The q_e experimental and calculated values for pseudo second order kinetics were in good agreement with each other as compared to pseudo first order kinetics. Characterization of adsorbent was done through scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and Gas chromatography-mass spectrometry (GC-MS).