Study of Adsorption of Malachite Green on Dried Aspergillus versicolor (MTCC280) Biomass

Dyes are extensively used in textile, tannery, food, paper and pulp, printing industries to color their products. About 10-15% of the annual global production (2,80,000 tons) of dyes are discharged as effluent mainly by textile and paint industries. The majority of the dyes are toxic and cause damage to aquatic life. In this study biosorption of Malachite Green (MG) onto the lyophilised Aspergillus versicolor Biomass (AVB) was investigated with variation in pH, temperature, contact time, biosorbent concentration and dye concentration. Characterization of the dye-biosorbent interaction was studied by scanning electron microscopy. It was observed from the present study that the biosorption of Malachite green was maximum at pH 5.0, temperature of 30°C, and adsorbent concentration of 2g/L. The rate of adsorption was found to be very fast at the initial phase and the equilibrium reached within 270 min following the pseudo-second order rate kinetics. The adsorption process followed Freundlich Isotherm model. The treated and untreated AVB was characterized for the investigation of possible dye-biosorbent interaction and surface morphology by Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM) respectively. The results show that the present study may help designing a promising route towards bioremediation of the hazardous chemical MG.