大块液膜技术处理含六价铬废水

以磷酸三丁酯(TBP)为载体,煤油为稀释剂,NaOH为反萃剂,采用大块液膜技术处理含95~100mg/LCr(VI)的模拟废水。考察了液膜相用量、载体体积分数及反萃剂浓度对大块液膜过程中Cr(VI)传质过程的影响。结果表明,大块液膜技术对废水中Cr(VI)的去除效果较好。Cr(VI)迁移速率随TBP体积分数的提高而加快。当反萃剂NaOH浓度大于0.5mol/L时,反萃剂浓度对Cr(VI)传质过程的影响较小。处理后废水中Cr(VI)含量降至0.5mg/L以下,达到国家排放标准。     

梯形波脉冲筛板萃取柱传质性能

本文以UO_2(NO_3)_2—30％TBP(KO)为实验体系,进行了梯形波脉冲筛板柱传质性能的研究。实验中测量了两组分的两相稳态浓度剖面共13组,以扩散模型为基础,求得了梯形波脉冲柱的“真实”传质单元高度HTU_(ox),分散单元高度HDU及表观传质单元高度HTU_(oxp)。通过对实验结果进行分析,选择出了适于本实验体系的较好的操作条件。     

锝的TBP萃取化学行为研究

报道了在硝酸体系中用３０％ＴＢＰ－正十二烷萃取Ｔｃ（Ⅶ）的实验结果。详细研究了硝酸、硝酸铀酰、硝酸铀（Ⅳ）、硝酸铵、亚硝酸钠、硝酸锆、硝酸钚、硝酸铈，亚硝酰钌、硝酸羟胺、硝酸肼浓度及温度、相比等因素对Ｔｃ（Ⅶ）萃取化学行为的影响。实验结果表明，在不含铀的硝酸体系中，硝酸、硝酸铵、硝酸钚、硝酸锆、硝酸铈、亚硝酸酰钌浓度及萃取温度对Ｔｃ（Ⅶ）的分配比影响很大，而亚硝酸钠、硝酸肼及硝酸羟胺浓度对Ｔｃ（Ⅶ）的分配比影响较小；在含铀的硝酸体系中，硝酸浓度对Ｔｃ（Ⅶ）的分配比有影响，而萃取温度、硝酸钚、锆的影响较小。Ｔｃ（Ⅶ）在含或不含铀的硝酸体系中，与ＴＢＰ分别形成ＵＯ２ＮＯ３·ＴｃＯ４·２ＴＢＰ和ＨＴｃＯ４·３ＴＢＰ萃合物。     

Magnetic Properties of Uranium Carbides after Neutron Irradiation

Fundamental investigations on valence control and solvent extraction of americium were carried out to develop a method for americium separation from reprocessing solution. In order to adjust americium valency from III to IV and VI, (NH₄)₁₀P₂W ₁₇O₆₁ synthesized was used as complexant stabilizing Am(IV). Oxidation behavior of americium was investigated as a function of (NH₄)₁₀P₂W ₁₇O₆₁ americium ratio. Using 0.1M (NH₄)₂S₂O₈ and 0.01M AgNO₃ as oxidation reagent, Am(IV) was obtained quantitatively at the ratio of 15. On decreasing the ratio to 0.6, 92% of americium was adjusted to Am(VI). The concentration of (NH₄)₂S₂O₈ could be reduced to 1/15 compared to the previously reported method in which no complexant was used. Americium(IV) was also prepared by reacting O₃ and AgNO₃ but no Am(VI) was obtained even at low (NH₄)₁₀P₂W ₁₇O₆₁ to americium ratio.

Americium(VI) could be extracted by tri-n-butyl phosphate stably without influence of (NH₄)₁₀P₂W ₁₇O₆₁. The distribution coefficient of Am(VI) was 4 between 100% tri-n-butyl phosphate and 1 M nitric acid, and separation factor from Nd(III) was 50.

With regard to the americium separation method which implemented valence control followed by extraction, adding (NH₄)₁₀P₂W ₁₇O₆₁ led to minimization of waste volume and improvement of extraction efficiency.     

磷酸三丁酯和磷酸二丁酯与Pu(Ⅳ)配合物的密度泛函研究

采用B3LYP密度泛函方法,Pu(Ⅳ)和其他原子分别采用相对论有效原子实势(RECP)和6-311g(d,p)全电子基组,研究了Pu(NO3)4TBP2和Pu(NO3)2DBP2的几何结构、热力学参数及紫外可见光谱。几何结构计算结果表明,由于配体空间位阻的影响,Pu与DBP的键长更短,自然布居分析(NPA)结果也表明,Pu与DBP之间的电荷转移更多,因此二者之间相互作用更强。热力学分析显示,Pu(NO3)4TBP2与HDBP发生配体交换的反应自由能为-178.9kJ/mol,说明DBP与Pu之间的相互作用更强。Pu(NO3)4TBP2的紫外吸收光谱主要来源于硝酸根到Pu的f轨道的跃迁,TBP贡献不大;而Pu(NO3)2DBP2的跃迁同时来源于硝酸根和DBP到Pu的f轨道的配体-金属电荷转移跃迁(LMCT)。     

ASTM D-5307 and ASTM D-7169 SIMDIS Standards: A Comparison and Correlation of Methods

TBP curves are essential in process simulators of the refining industry, particularly for the heaviest fractions of crude oils. ASTM D-7169 and ASTM D-5307 are standards used in simulated distillation analysis for fast characterization of these fractions. In this report, correlations to convert data from the first one to the second-mentioned standard are reported. These correlations were obtained from our analytical laboratory and pilot plant experimental data, gathered so far.     

异羟肟酸型配位体对TBP萃取钚行为的影响研究

为有效地去除铀产品中的钚,以乙异羟肟酸和丙异羟肟酸为无盐配位体,用单级萃取分配法,对ＴＢＰ萃取Ｐｕ（Ⅳ）行为进行了研究。探讨了时间、酸度、配位体浓度、相比、温度、磷酸二丁酯（ＨＤＢＰ）浓度、Ｐｕ价态等因素对分配比Ｄ的影响。研究结果表明,异羟肟酸型配位体对Ｐｕ（Ⅳ）有很好的配位效果。     

在UO_2(NO_3)_2-TBP-CCI_4有机相中光化还原制备铀(Ⅳ)的研究

本文的目的是研究在TBP有机相中光化还原铀(Ⅵ)以制备铀(Ⅳ)。选用了高压汞灯作为激发光源,CCl_4为TBP的稀释剂。研究了反应温度、原始水相溶液组成等因素对铀(Ⅳ)产额和亚硝酸生成量的影响。推荐了制备铀(Ⅳ)的适宜条件。     

石油馏分三种蒸馏曲线数学模型的研究

石油馏分三种蒸馏曲线换算的经验计算图表,依然是炼油工业设计、生产和科研中广泛使用的计算方法。但文献中有关石油馏分三种蒸馏曲线相关模型形式复杂、相对误差大,只能单向换算。本文研究了石油馏分的恩氏蒸馏曲线分别与实沸点蒸馏曲线、平衡汽化蒸馏曲线各段温差关系图之后,提出一个形式简单、误差相对小、能双向换算的新数学模型。结果表明:其计算结果与该曲线给出的数值吻合好,计算准确度高,明显优于前人的模型。