Biosorption of copper (II) from aqueous solutions by wheat shell Original Research Article

The adsorption capacity of wheat shell for copper (II) was studied at various pH (2–7), agitation speeds (50–250 rpm) and initial metal ion concentrations (Co, from 10 to 250 mg.L−1). Maximum biosorption of copper onto wheat shell occurred at 240 rpm agitation speed and at pH between 5 and 6. The biosorption values of copper (11) were increased with increasing pH from 2 to 5 and decreased with increasing copper/wheat shell (x/m) ratios from 0.83 to 10.84 mgCu(II).g−1 wheat shell. The biosorption efficiencies at these x/m ratios were 99% and 52%, respectively, at the end of the 120 min contact time (t). The equilibrium isotherms and kinetics were obtained from batch adsorption experiments at 298 K. It was observed that wheat shell was a suitable biosorbent for removing Cu(II) from aqueous solutions.