Biodecolorization of dyes using low cost adsorbents

The identified biosorbents were examined to treat the basic dyes of Methylene Blue, Malachite Green and Basic Blue from aqueous solution in batch mode. The biosorbents used were Effective Microorganisms (EM) based Kitchen waste Compost, Effective Microorganisms based Leaf waste Compost, Effective Microorganisms based Paper waste Compost and Effective Microorganisms based Water Hyacinth plant waste Compost. The batch experiments were conducted to optimize the operating parameters like pH (2-9), adsorbent dosage (2-10 g/L), particle size of adsorbent (0.6 ¿ 2.36 mm), temperature (25 ¿ 45C), contact time (0¿500 min) and initial dye concentration (50¿1000 mg/L). Various isotherm models (Langmuir, Freundlich, Redlich-Peterson, Toth and Sips) were identified to know the functional relationship between the sorbent and sorbate. All the models predicted the experimental data well with high correlation coefficient and less percentage error. Batch desorption experiments were performed to identify the best elutant. The best performed compost under batch operation was used to study applicability under continuous mode of operation.