| In this paper, we used nano-material as sorbents. The adsorptive capability and mechanism of Tl on nano-material in the different temperature, pH value, and concentration were studied in thesis. The research contents and experimental results as follows:1. Among the experiment mainly research the material conditions of Cadion 2B spectrophotometry to determine thallium, and the best conditions of Cadion 2B spectrophotometry to determine thallium are as follow: The dosage of different reagents are: 5.0 mL pH 12 NH3?H2O buffer solution, 1.0 mL 1% Triton X-100 solution and 1.5 mL Cadion 2B. The best pH of solution was 4.5, after 10 min the color development reaction completeded, steadied in 12 h, the wavelength of largest absorption was 500 nm, and the apparent molar absorptivity was 7.29×104 L·mol-1·cm-1.2. Both adsorption and desorption of nano-TiO2 and nano-Al2O3 to Tl(Ш) ions depended on the initial pH of the solution. The Tl(Ш) ions can be adsorbed and desorbed quantificationally at proper pH values. The optimum pH value to adsorb Tl(Ш) ions from solution was considered to be 4.5, after ultrasonically dispersed for 1 min and static adsorption for 15 min, and the adsorption percentage was closed to 100%. 1mol/L HCl was used for the desorption of Tl(Ш) on nano-Al2O3, and water for the desorption of Tl(Ш) on nano-TiO2 by microwave irradiation. The maximum adsorption capacity of thallium ions on nano-TiO2 and nano-Al2O3 were 4.09 mg g- 1, 5.78 mg g-1 at room temperature, respectively. The enrichment factor values of nano-TiO2 and nano-Al2O3 were 12.5 and 25, respectively.3. The adsorption of Tl(III) ions on nano-TiO2 and nano-Al2O3 properly correlate with the second-order rate equation, thus, the type of the adsorption are chemical adsorption. The rate constant of second-order adsorption of nano-TiO2 and nano-Al2O3 were 4.55 g mg- 1min- 1, 11.89 g mg- 1min- 1, respectively. The activation energy of nano-TiO2 and nano-Al2O3 were 13.20 kJ mol-1, 19.02 kJ·mol-1, respectively. 4. The Langmuir model could describe the adsorption of nano-TiO2 and nano-Al2O3 to Tl(Ш) ions successfully over the whole range of concentration studied. The value of standard enthalpy and standard entropy (ΔH0,ΔS0 >0) may be interpreted as the endothermic adsorption process. The negative value ofΔG0 showed the adsorptions of thallium by nano-TiO2 and nano-Al2O3 were spontaneous process. The adsorption energy of nano-TiO2 and nano-Al2O3 were 12.06 kJ·mol-1, 8.39 kJ·mol-1, respectively, which indicate that the process belongs to chemical adsorption.5. The detection limits of determining Tl(Ш)ions with nano-TiO2 and nano-Al2O3 as sorbents were 0.09μg mL-1and 0.84μg mL-1, respectively, and the relative standard deviations were 6.18% and 2.37%, respectively. Except for Cd(II), Cu(II), Pb(II), Mn(II), other coexisting ions almost didn't have effects and the allowable volume for these species were large. Water and practical samples have been analyzed by this enrichmental way. The results are accord to the reference.
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