摘要
多孔载体支撑钯膜可广泛应用于氢气分离纯化领域。其中,多孔金属负载钯膜具有密封可靠、机械强度高等优点。但钯膜与多孔金属高温下易发生成分互扩散,导致其氢渗透性能降低。针对多孔金属负载钯膜高温稳定性差的问题,采用浆料涂敷法在多孔316L不锈钢管表面制备了氧化钛层作为扩散阻挡层。通过氢气高温烧结提高氧化钛层与多孔不锈钢载体间的结合强度。氧化钛修饰多孔不锈钢管的平均孔径为1.1μm。采用化学镀方法在氧化钛修饰多孔不锈钢管表面制备了钯膜。通过扫描电镜-能谱分析(SEM-EDS)和X射线衍射(XRD)表征了钯膜的结构、形貌和成分分布。多孔不锈钢管表面钯膜致密,厚度为5μm,为单一面心立方相。钯膜与氧化钛层结合紧密。对多孔不锈钢管表面钯膜进行了氢渗透性能测试,钯膜与多孔不锈钢载体未发生元素互扩散。在723 K,0.5 MPa压差条件下,钯膜的氢渗透率为1.58×10^(-3) mol·m^(-2)·s^(-1)·Pa^(-0.5),氢氮选择系数为1700,氢渗透激活能为15.46 kJ·mol^(-1)。
Palladium membrane has excellent selective permeability to hydrogen. It can be widely used in the fields of catalysis,dehydrogenation,hydrogenation,hydrogen separation and purification. The conventional palladium membrane preparation technology is mainly based on cold-rolling method,and the obtained palladium membrane has a large thickness,a high cost,and a low hydrogen permeation efficiency. In recent years,porous materials supported palladium membranes have received extensive attention from researchers. The thickness of palladium membrane was greatly reduced,and the hydrogen permeation efficiency was remarkably improved. Porous metal used as support for palladium membrane had advantages of excellent sealing performance and high mechanical strength. However,component inter-diffusion tended to happen between palladium membrane and the porous metal support at high temperatures,resulting in a decrease in hydrogen permeability. In this study,a 316L stainless steel tube was used as support of palladium membrane. In order to improve high temperature stability of porous metal supported palladium membrane,titania barrier was prepared by dip-coating method. Then,the porous support was activated and palladium membrane was prepared by electroless plating onto titania modified porous 316L stainless steel tube. X-ray diffraction(XRD)and scanning electron microscopy-energy spectroscopy(SEM-EDS)were used to study the structure,morphology and composition distribution of palladium membrane. The hydrogen permeation of palladium membrane was tested,and the thermodynamic and kinetic mechanisms of hydrogen permeation in palladium membranes were investigated. The titania suspension was prepared by ball milling for 24 h. It contained titania powder with particle size of200 nm,ethanol as solvent and polyvinyl butyral as binder. The prepared titania suspension was stable with particles uniformly dispersed. Then,titania suspension was coated on the surface of porous 316L stainless steel tube by dip-coating method,and calcined at high tem
作者
李梦珠
李帅
吕琴丽
王舟欣
王树茂
Li Mengzhu;Li Shuai;Lv Qinli;Wang Zhouxin;Wang Shumao(Institute of Energy Materials and Technology,GRIMAT Engineering Institute Co.Ltd.,Beijing 100088,China)
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2022年第4期471-479,共9页
Chinese Journal of Rare Metals
基金
国家重点研发计划项目(2016YFB0600102,2016YFB0600103)资助。
关键词
多孔316L不锈钢
氧化钛
钯膜
化学镀
氢渗透率
porous 316L stainless steel tube
titania
palladium membrane
electroless plating
hydrogen permeation
