Sorption of crystal violet from aqueous solution using live roots of Eichhornia crassipes: Kinetic, isotherm, phyto and cyto-genotoxicity studies

Abstract

In the present study, Water hyacinth (Eichhornia crassipes), a worst obtrusive aquatic weed has utilized for biosorption of cationic dye, crystal violet from aqueous solution. To evaluate the biosorption capacity, the effect of solution pH, initial dye concentration, and contact time were investigated. The highest qe was observed at pH 7 and biosorption capacity was experiential up to dye concentration 1 gL−1. Kinetic data was fitted well to the pseudo-second order kinetics with R2=0.993 and qe=19.84 mg g−1 at concentration 100 mgL−1. Other adsorption models like pseudo-first order with R2=0.947 and intraparticle diffusion R2=0.785 were also operated for the mathematical description of the sorption kinetics. The Freundlich isotherm model fitted well to the adsorption data with R2=0.999, kf= 5.039 mg g−1 and 1/n = 0.535. The other equilibrium data were also mathematically described using Langmuir (R2=0.941), Dubinin–Radushkevitch (D–R)​ (R2=0.936) and Temkin (R2=0.978) isotherm models. UV–Vis and FT-IR analyses were executed to accomplish the decolorization of crystal violet from aqueous solution. In addition, phytotoxicity and cyto-genotoxicity analyses were prosecuted. The results indicated that the solution spawned were far less toxic than the crystal violet solution. These results consigned that E. crassipes is effective in decolorizing crystal violet dye and could be auspicious in phytoremediation of dye contaminated wastewater.