Removal of Crystal Violet dye from aqueous solution using water hyacinth: Equilibrium, kinetics and thermodynamics study

Abstract

Effluent water from dyeing industries has now for long been a taxing issue. Of the various dyes which are extremely toxic, CrystalViolet whichis used in the dyeing industry is known for its mutagenic and mitotic poisoning nature.Water hyacinth (Eichhornia crassipes) is a perennial aquaticplant notorious for its rapid invasive growth on the surface of water bodies causing ill-effects on the biodiversity. The potential of powdered rootsof water hyacinth was studied for decolorization of Crystal Violet dye. Influence of parameters such as initial pH (2.0–10.0), initial dyeconcentration (100–500 ppm), biosorbent dosage (0.5–5 g/l), contact time (10–240 min) and temperature (300–323 K) were examined. Maximumremoval of dye was observed at pH 7.8. The obtained data were fit into different kinetic models and the biosorption was found to follow pseudosecond order kinetic model. The Langmuir monolayer biosorption capacity of water hyacinth was estimated as 322.58 mg/g. The study hasdemonstrated water hyacinth as a potential low cost biosorbent for effective removal of Crystal Violet dye from aqueous solution.