Wang Z.,Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education |
Wang C.,Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education |
Wang P.,Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education |
Wang P.,Hohai University |
And 3 more authors.
Water, Air, and Soil Pollution | Year: 2014
Cyanobacterial toxins have caused world-wide concern because of their lethal effects, which has led to intensive search of cost-effective removal techniques. With the application of a Box-Behnken experimental design combined with response surface methodology, the adsorption process of the potent and commonly occurring microcystin-LR (MC-LR) onto nanosized montmorillonite (NMMT) K10 was investigated through the HPLC-UV system. The quadratic statistical model was established to predict the interactive effects of pH (1-12), NMMT K10 dose (1-10 mg mL-1), and MC-LR initial concentration (100-1,000 μg L-1) on MC-LR adsorption and to optimize the controlling parameters. The MC-LR adsorption by NMMT K10 was pH dependent and was found to reach a maximum at pH 2.96 with a removal peak of 186.37 μg g-1. The range of optimal pH for MC-LR adsorption was 2.96-3.48, and higher adsorption capacities were achieved with increasing adsorbent dose and MC-LR initial concentration. Sorption kinetics revealed that the sorption process of MC-LR on NMMT K10 was rapid (short equilibrium time) and involved several kinetic stages. The Langmuir isotherm model predicted that the theoretical maximum adsorption capacity at pH 3 was 285.20 μg g-1. Alkali eluting media (0.1 M NaOH) showed the highest desorption percentage (75.3%) during regeneration studies. The high Brunauer-Emmett-Teller (BET) specific surface area (204.65 m2 g-1) of NMMT K10 was also characterized. NMMT K10 was determined to be an effective and economic adsorbent for MC-LR removal on a large scale. © Springer International Publishing 2014.