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Th4(PO44P2O7和ZrP2O7的合成及其对Eu(Ⅲ)和Am(Ⅲ)的吸附行为研究

Synthesis of Thorium Phosphate Diphosphate and Zirconium Diphosphate, and the Sorption of Eu(Ⅲ) and Am(Ⅲ) on the Synthesized Sorbents

【作者】 王冬林

【导师】 吴王锁;

【作者基本信息】 兰州大学 , 无机化学, 2008, 硕士

【摘要】 本文采用静态法研究了镧系元素Eu(Ⅲ)和锕系元素Am(Ⅲ)在合成吸附剂Th4(PO44P2O7和ZrP2O7上吸附行为特征。Eu(Ⅲ)和Am(Ⅲ)在Th4(PO44P2O7吸附研究主要包括吸附平衡时间、固液比、pH值、离子强度以及FA等因素对吸附的影响。实验结果表明,在开始的10 h内,Eu(Ⅲ)和Am(Ⅲ)在Th4(PO44P2O7上的吸附率随着时间的增加而增大,分别选择16h和20h作为吸附平衡时间。当固液比由1.67g/L增加到20.00g/L,Eu(Ⅲ)和Am(Ⅲ)在Th4(PO44P2O7上的吸附率随着固液比的增加而增大,选择m/v=10.00g/L作为后续吸附实验的固液比。Am(Ⅲ)和Eu(Ⅲ)在Th4(PO44P2O7上的吸附具有相似的pH吸附曲线,pH的变化对吸附的影响较大,吸附率在pH=2到5时出现剧增现象。在其他条件相同时,离子强度从0.01mol/L增大到0.1mol/L KNO3,吸附率随着离子强度的增大而减小。通过对比实验发现,FA对Am(Ⅲ)和Eu(Ⅲ)在Th4(PO44P2O7上的吸附具有促进的作用。Eu(Ⅲ)和Am(Ⅲ)在ZrP2O7吸附研究主要针对吸附平衡时间、固液比、pH值、离子强度以及FA等因素影响进行了初步研究。实验结果表明,本实验选取15h分别作为Eu(Ⅲ)和Am(Ⅲ)在ZrP2O7上的吸附平衡时间。当固液比由1.25g/L增加到30.00g/L,Eu(Ⅲ)和Am(Ⅲ)在ZrP2O7上的吸附率随着固液比的增加而增大,选择m/v=5.00g/L作为后续实验的固液比。Am(Ⅲ)和Eu(Ⅲ)在ZrP2O7上的吸附具有相似的pH吸附特征,pH值是影响吸附的主要因素之一。吸附率在pH=1到3时出现剧增现象。在其他条件相同时,离子强度从0.01mol/L增大到0.1mol/L KNO3,吸附率随着离子强度的增大而基本保持不变。通过对比实验发现,FA对Am(Ⅲ)和Eu(Ⅲ)在ZrP2O7上的吸附具有促进的作用。Am(Ⅲ)和Eu(Ⅲ)在Th4(PO44P2O7和ZrP2O7表面可能形成了表面络合物。吸附剂的表面特征及其吸附机理研究是进一步深入研究的重点。

【Abstract】 The sorption characteristics of lanthanides element Eu (Ⅲ) and actinides element Am (Ⅲ) onto synthesis absorbent of Th4(PO44PaO7 and ZrP2O7 were studied by a batch technique.Sorption of Eu(Ⅲ) and Am(Ⅲ) on thorium phosphate diphosphate as a function of equilibrium time, the ratio of adsorbent mass to solution volume (m/v), pH, ionic strength and fulvic acid (FA) were studied under ambient condition using batch technique. The experimental results indicated that the sorption rate of Eu(Ⅲ) and Am(Ⅲ) on thorium phosphate diphosphate increased with increasing sorption time in the first 10 hours. 16hours and 20hours were selected as sorption equilibrium time, respectively. The sorption rate of Eu(Ⅲ) and Am(Ⅲ) on thorium phosphate diphosphate increased with increasing m/v from 1.67g/L to 20.00g/L. 10.00g/L was chosen as the ratio of solid to liquid of follow-up sorption experiment. Sorption of Eu(Ⅲ) and Am(Ⅲ) on thorium phosphate diphosphate were strongly affected by pH values , as compared Eu(Ⅲ) and Am(Ⅲ) sorption on the same adsorbent, the Eu(Ⅲ) and Am(Ⅲ) sorption on thorium phosphate diphosphate had the similar pH sorption curves. The sorption of Eu(Ⅲ) and Am(Ⅲ) increased steeply with increasing pH from 2 to 5. When other conditions were the same, the sorption rate of Eu(Ⅲ) and Am(Ⅲ) on thorium phosphate diphosphate decreased with increasing ionic strength from 0.01mol/L to 0.1mol/L KNO3. The positive effect of FA on the sorption of Eu(Ⅲ) and Am(Ⅲ) on thorium phosphate diphosphate were found from the compared studies.Sorption of Eu(Ⅲ) and Am(Ⅲ) on zirconium diphosphate as a function of equilibrium time, the ratio of adsorbent mass to solution volume (m/v), pH, ionic strength and fulvic acid (FA) were studied under ambient condition using batch technique. The experimental results indicated that 15 hours was chosen as sorption equilibrium time of Eu(Ⅲ) and Am(Ⅲ) on zirconium diphosphate. The sorption rate of Eu(Ⅲ) and Am(Ⅲ) on zirconium diphosphate increased with increasing m/v from 1.25g/L to 30.00g/L. 5.00g/L was selected as the ratio of solid to liquid of follow-up sorption experiment. pH values was the impact of one of the main sorption factors, as compared Eu(Ⅲ) and Am(Ⅲ) sorption on the same adsorbent, the Eu(Ⅲ) and Am(Ⅲ) sorption on zirconium diphosphate had the similar pH sorption characteristics. The sorption rate of Eu(Ⅲ) and Am(Ⅲ) increased steeply with increasing pH from 1 to 3. When other conditions were the same, the sorption rate of Eu(Ⅲ) and Am(Ⅲ) on zirconium diphosphate maintained invariable basically with increasing ionic strength from 0.01mol/L to 0.1mol/L KNO3. The positive effect of FA on the sorption of Eu(Ⅲ) and Am(Ⅲ) on zirconium diphosphate were found from the compared studies.It was assumed that surface complexes were formed on the surface of thorium phosphate diphosphate and zirconium diphosphate. The study of adsorbent surface characteristics and sorption mechanism are the important aspects of farther experiment.

  • 【网络出版投稿人】 兰州大学
  • 【网络出版年期】2008年 12期
  • 【分类号】O611.3
  • 【下载频次】56
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