Efficient extraction of antimony(III) by titanate nanosheets: Study on adsorption behavior and mechanism

Antimony has been listed as a critical pollutant in many countries because of its toxic effects on earth organisms. In this study, titanate nanosheets (TNS) were prepared with a high specific surface area by alkaline hydrothermal method. The adsorption mechanism and adsorption capacity of removing Sb(III) from aqueous solutions with TNS as an adsorbent were investigated for the first time. The FTIR and XPS analysis indicated that the interlayer sodium ions of TNS were responsible for Sb(III) adsorption. The batch experiments were conducted on solution pH, adsorbent dosage, initial concentration and reaction time. The results exhibited that when pH was 2, the removal rate was about 90% with the dosage of TNS was 0.1 g/L. The adsorption reaction was exceedingly rapid in the initial 5 min, and then the reaction was in equilibrium after about 30 min. The experimental data were better fitted with Langmuir isotherm model, and the maximum adsorption amount could attain 232.56 mg/g. The experiments showed that TNS had outstanding anti-interference performance to common cations. Therefore, TNS were considered to be an excellent material for removing Sb(III) from aqueous solutions.