合成了吡啶吡唑基配体C8-BPP[2,6-bis(5-(n-octyl)-1H-pyrazol-3-yl)pyridine],并采用红外光谱、核磁共振波谱、质谱等手段对其进行了表征.以正十二烷为稀释剂,2-溴己酸为协萃剂,研究了C8-BPP从HNO3溶液中萃取Am3+和Eu3+的行为.重点考察了萃取时间、酸度和萃取剂浓度等对分配比D和分离因子SFAm/Eu的影响.在HNO3浓度为0.2~1.0 mol/L时,C8-BPP萃取Am3+和Eu3+的D值随HNO3浓度增加而减小,SFAm/Eu值先增大后减小;HNO3浓度为0.5 mol/L时,SFAm/Eu达到55.随着配体浓度的增加,C8-BPP萃取Am3+和Eu3+的D值均增加,SFAm/Eu值缓慢减小,但仍在40以上.斜率分析表明,C8-BPP萃取Am3+和Eu3+均形成了1: 1型的萃合物.还采用紫外滴定、高分辨质谱、红外光谱、拉曼光谱和时间分辨荧光光谱等方法研究了C8-BPP与Eu3+的配位化学行为,并得到了配合物的组成和稳定常数.
Pyridylpyrazole based ligand 2,6-bis [ 5- (n-octyl) - 1H-pyrazol-3-yl ] pyridine ( C8-BPP ) was syn- thesized and characterized by means of mass spectrometry (MS), nuclear magnetic resonance (NMR) spec- trometry, and Fourier transform infrared spectrometry (FTIR). In the presence of 2-bromohexanoie acid, using n-dodecane as diluent, the extraction behaviors of Am^3+ and Eu^3+ with C8-BPP were investigated. Influences of diluent, contact time, acidity and the ligand concentration on the extraction of Am^3+ and Eu^3+ were evaluated in HNO3 solution. The distribution ratio values of Am^3+ and Eu^3+ decreased with increasing HNO3 concentration from 0. 2 to 1.0 mol/L, and increased with increasing ligand concentration from 0.01 to 0. 1 mol/L. With the increase of acidity, the separation factors (SFAm/Eu) increased firstly and then decreased. The maximum value of SFAm/Eu can reach 55 at 0. 5 mol/L HNO3. Meanwhile, SFAm/Eu values decreased slowly with increasing the ligand concentration but all the SFAm/Eu values were above 40. The extraction results also showed that C8-BPP exhibited good selective extraction ability for Am^3+ over RE^3+. Moreover, slope analyses indicated the formation of 1 : 1 complexes of C8-BPP with Am^3+ and Eu^3+, separately. Besides, the complexation behaviors of C8-BPP with Eu^3+ were also investigated by means of UV-Vis spectrometry titration, electrospray ionization mass spectrometry( ESI-MS ), FTIR, Raman spectrometry and time-resolved laser-induced fluorescence spectroscopy (TRLFS). The composition and stability constant(lgK) of the complex of C8-BPP with Eu^3+ were also obtained.