Measurement of diffusive and surface transport resistances for deuterium in palladium-coated zirconium membranes
Measurement of diffusive and surface transport resistances for deuterium in palladium-coated zirconium membranes
复制标题
钯涂层锆膜中氘的扩散和表面传输阻力的测量
DOI：
10.1016/0022-3115(92)90531-o
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发表时间：
1992
影响因子：
3.1
通讯作者：
P. C. Hsu
中科院分区：
文献类型：
--
作者：
R. Buxbaum;P. C. Hsu
镀钯的锆膜是低压、高温氢和氢同位素提取的理想选择，例如从裂变和聚变冷却液中提取氢和氢同位素。将存在的氢气氧化成水(氧化萃取法)是提供非常低的下游氢气压力的好方法，有时需要这种压力来驱动萃取法。本文给出了在600-700K温度和2.7×10-−2-6.7×10-−-4Pa.7×10-10-4 Pa.7×10-4Pd压力下，氢通过锆钯膜传输的实验数据和理论处理。我们还提出了一种分析实验流量测量的新技术，以计算此类实验中的有效渗透系数和粘着系数。在很低的压力下，分子在钯表面的吸附限制了它的迁移；这种吸附的粘着系数是LOGσ=−0.676−0.0021(T−273)。在较高的上游压力下，锆石的渗透率限制了运移，PZr=2.00×10-6exp(59/T)±40%−/mspa-1.这些渗透率值略高于预测值。我们没有发现由表面氧化或界面效应引起的额外输运阻力的证据。膜被使用了几个月，没有显示出变质的迹象。
Palladium-coated zirconium membranes are attractive choices for low pressure, high temperature hydrogen and hydrogen isotope extractions, eg from fission and fusion coolant fluids. Oxidizing the exiting hydrogen to water (oxidative extraction) is a good way of providing very low downstream hydrogen pressures that are sometimes needed to drive the extraction. We present here experimental data and a theoretical treatment of deuterium transport through Zr-Pd membranes at temperatures of 600–700 K and upstream deuterium pressures of 2.7× 10− 2 to 6.7× 10− 4 Pa. We also present a new technique for analyzing experimental flux measurements for calculating the effective permeation and sticking coefficients during such experiments. At very low pressures, transport is limited by molecular adsorption on the palladium surface; the sticking coefficient for this adsorption is log σ=− 0.676− 0.0021 (T− 273). At higher upstream pressures, permeability in zirconium limits transport; P Zr= 2.00× 10− 6 exp (59/T)±40% mol/msPa 1 2. These permeability values are slightly higher than predicted. We find no evidence for additional transport resistance caused by zirconium surface oxidation, or from Zr-Pd interface effects. Membranes were used for several months without showing signs of deterioration.