Abstract:
Discharge of chromium containing water solution into the environment poses a serious
environmental and health problem. There is need for environmentally friendly and cost-effective
methods for removal of chromium containing water. The main objective of present study is to
investigate the adsorptive removal of chromium (VI) from aqueous solution using activated
Carbon of Erythrinaabyssinica (AC-EA) &Enseteventricosummidrib leaf (AC-EVML) because
it is high removal capacity, low cost and easy accessibility. Activated Carbon EVML and EA
adsorbents were prepared Sulfuric acid activation method at 100 0C. Characterization of these
adsorbents such as physicochemical parameter, point pf zero charge, Fourier transform infrared
radiation spectroscopy, surface area and X-ray diffraction was done prior to bio sorption process.
activated adsorbents were assessed in batch mode adsorption experiment for percentage
chromium removal and milligrams per gram chromium uptake as a function of contact time, pH,
and initial concentration. Results showed maximum removal efficiency for Cr (VI) at 9 h and 6 h
contact time, by AC-EVML and AC-EA, respectively at 0.1 g and pH 2. Percentage removal of
Cr (VI) increased with increasing contact time (from 0.5 h to 12 h). Sorption kinetics of
chromium adsorption by activated adsorbents was predicted reliably using a pseudo-first order,
pseudo-second order and intra particle diffusion model. The kinetic adsorption data well fitted to
pseudo-second order. Equilibrium uptakes were evaluated using Langmuir, Freundlich and
Temkin adsorption isotherm models and the equilibrium data well fitted into Langmuir isotherm.
The study demonstrated the efficiency of activated adsorbents and presents it as a viable low-cost
adsorbent for bioremediation.
