Biosorption of Ca(II), Cu(II), Pb(II) from aqueous solution by a novel adsorbent of ferric hydroxide-loaded sugar beet pulp

A novel adsorbent was prepared from sugar beet pulp (SBP). SBP was saponified first, then loaded with FeCl3 and hydrolyzed. The adsorption properties of Ca2+, Cu2+, and Pb2+ by ferric hydroxide-loaded sugar beet pulp (SBPSFH) were studied. The effect of pH, adsorption time, initial concentration of ions, temperature and adsorbent dosage were studied on the adsorption process. In addition, the SBP and SBPSFH were characterized by SEM, XRD and FTIR. The results show that the SBPSFH has significantly improved the uptake of metal ions. At 40 degrees C and pH 4.5-5.0, the adsorption of Ca2+, Cu2+ and Pb2+ by SBPSFH reached the equilibrium within 30 min. The optimal dosage was 10, 10, 5 g L-1, and the maximum adsorption capacity was 21.57, 38.25, 108.18 mg g(-1), respectively. The adsorption data fitted well with the pseudo-second-order model and the adsorption isotherm conformed to the Langmuir equation, indicated that the adsorption process is dominated by monomolecular chemical adsorption. The thermodynamic parameters (Delta G degrees, Delta S degrees and Delta H degrees) showed that the adsorption is feasible, spontaneous and endothermic.