Biosorption of Cd (II) and As (III) ions from aqueous solution by tea waste biomass

Biosorption of Cadmium (Cd (II)) and Arsenic (As (III)) ions from wastewater by tea waste biomass was examined in a batch experimental setup. The effects of pH and temperature on the biosorption were studied in this work. The optimum pH for the maximum efficiency of biosorption of Cd (II) and As (III) were found to be 5.5 and 7.5, respectively. The adsorption process was endothermic in nature and spontaneous. About 95 and 84.5% removal of Cd (II) and As (III) ions was obtained at 200 mg/l of adsorbate and 6 g/l and 7 g/l of adsorbent dosage, respectively. The present study showed that tea waste biomass can serve as a good and cheap substitute for conventional carbon- based adsorbents.Key words: Tea waste biomass, Cd (II), As (III), biosorption

A POTENTIAL OF BIOSORBENT DERIVED FROM BANANA PEEL FOR REMOVAL OF As (III) FROM CONTAMINATED WATER

ABSTRACT: The main aim of this work is to evaluate the potential of application of banana peel (BP) as a biosorbent for removal of As(III) ion from contaminated water. Characterization of biosorbent was analyzed with FTIR, EDX and SEM. Equilibrium isotherms and kinetics were obtained and the effects of solution pH, temperature, dosage and contact time were studied in batch experiments. Maximum percentage removal (82.23%) of As(III) ion was obtained at optimized pH 7, contact time (tc) of 90 min, dosage (d c ) of 8 g, temperature (t c ) of 35 o C and 10 mg/l As(III) ion concentration (C i ), respectively. Equilibrium was well described by Freundlich isotherm model (R 2 = 0.993). Moreover, it was also found that sorption kinetics favour pseudo-second order model with high linear regression coefficient (R 2 = 0.998)

Biosorptive behaviour of mango leaf powder and rice husk for arsenic(III) from aqueous solutions

The present study deals with the biosorption of As(III) from aqueous solution using mango leaves powder (MLP) and rice husk (RH) in a batch operation. Scanning electron microscopy and Fourier transformation infrared spectrometry analysis shows the surface texture of biosorbents and metal binding of functional groups of before and after biosorption of As(III). The optimum pH was obtained at 7 and 6 with 7 and 6 g/l of dosage of MLP and RH, respectively. The adsorption of As(III) onto MLP and RH was favourably influenced by an increase in temperature. Equilibrium data were well represented by the Freundlich isotherm model. Nitric acid and ethylenediaminetetra acetic acid was found to be a better eluant for the desorption followed by hydrochloric acid and sodium hydroxide of As(III) with a maximum desorption efficiency of 69.5, 48.5 and 79.4, 86.3 %, respectively. The pseudo-second-order kinetic model was found to best fitted of the experimental data over the equilibrium time at 32 h. The positive values of heat of adsorption (23.89 kJ/mol for MLP and 52.26 kJ/mol for RH) indicate the endothermic nature of the adsorption process. The thermodynamic study showed the spontaneous nature of the sorption of As(III) onto MLP and RH