Biosorptive removal of cadmium from contaminated groundwater and industrial effluents.
The cadmium removing capacity of a biosorbent Calotropis procera, a perennial wild plant, is reported here. The biomass was found to possess high uptake capacity of Cd(II). Adsorption was pH dependent and the maximum removal was obtained at two different pH i.e. pH 5.0 and 8.0. Maximum biosorption capacity in batch and column mode was found to be 40 and 50.5 mg/g. The adsorption equilibrium (> or =90% removal) was attained within 5 min irrespective of the cadmium ion concentration. Interfering ions viz. Zn(II), As(III), Fe(II), Ni(II) interfered only when their concentration was higher than the equimolar ratio. The Freundlich isotherm best explained the adsorption, yet the monolayer adsorption was also noted at lower concentrations of Cd(II). The FTIR analysis indicates the involvement of hydroxyl (-OH), alkanes (-CH), nitrite (-NO(2)), and carboxyl group (-COO) chelates in metal binding. The complete desorption of the cadmium was achieved by 0.1M H(2)SO(4) and 0.1M HCl. The C. procera based Cd(II) removal technology appears feasible.
Pandey
Piyush Kant
PK
Centre for Environmental Science and Engineering, Department of Engineering Chemistry, Bhilai Institute of Technology, Durg, 491 002 CG, India. drpiyush_pandey@yahoo.com
Verma
Yashu
Y
Choubey
Shweta
S
Pandey
Madhurima
M
Chandrasekhar
K
K
D000327:Adsorption; D001673:Biodegradation, Environmental; D018533:Biomass; D019149:Bioreactors; D002104:Cadmium / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D007477:Ions; D007700:Kinetics; D008670:Metals / Q000737:chemistry; D011786:Quality Control; D014865:Waste Disposal, Fluid / Q000379:methods*; D014873:Water Pollutants; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification / Q000379:methods*
D007220:Industrial Waste; D007477:Ions; D008670:Metals; D014873:Water Pollutants; D014874:Water Pollutants, Chemical; D002104:Cadmium