钯膜分子筛防毒‘铠甲’的制备及性能研究

Because of the significance of hydrogen in the field of industry and energy, the seperation and purify of hydrogen is always a hotspot in industry and academia. Dense, ultrathin palladium membrane (several micron in thickness) can be selectivitily permeated by hydrogen, and achieves high-effective and low-cost hydrogen seperation, and consequently is always the focusing keypoint of researchers in the world. So far, a crucial trouble to palladium membrane is its fragile chemical stability, that is palladium toxicosis causing the deactivation and even destruction of palladium membrane, which make it infeasible that the palladium membrane has pratical use in long-term. Current project proposes a new strategy for the defence and resistance from deleterious substance of palladium membrane. In this strategy a gas defence armor consisting of a micropore zeolite membrane is prepared onto the surface of palladium membrane. Because of the selective permeance of smaller molecular from the zeolite membrane, hydrogen molecules will priorly pass through the armor but deleterious substance not, thus the deleterious substances will be fenced out from the palladium membrane. For accomplishing this strategy, a new preparation method is developed that involves the controlled diffusion of aluminum-palladium interface for undamaged piling into Pd film and the following aluminum membrane transforming into zeolite membrane. The strategy principle of gas defence armor for palladium membrane and its preparation methods both shows innovative. Current project will promote developing high-effective hydrogen seperation technology, and has a great impact on hydrogen concerned industry and hydrogen clean energy, hence has important scientific and social meaning.

由于氢气在工业和能源中的重要地位，氢分离纯化一直是工业界和学术界关注的热点。致密超薄钯膜（几个微米厚）可以选择性透过氢，实现氢气廉价高效分离，成为各国研究者关注的重点。目前，钯膜技术面临的一个主要难题是钯膜的化学稳定性问题，即钯膜易中毒（或污染）而失活（或损毁），这使得钯膜难以长期稳定应用。本项目提出了一种钯膜防毒、抗毒的新策略，研究其制备方法及性能机理。该策略在致密钯膜表面制备微孔分子筛膜防毒'铠甲'，利用微孔分子筛膜小分子筛分特性，使氢气优先通过而有毒物质通行困难，从而将有毒物质和核心钯膜隔离，实现钯膜防毒、抗毒功能。为实现该策略，本研究采用铝钯膜界面扩散无损打桩，然后铝膜转化为分子筛膜的制备技术。本项目提出的钯膜防毒技术及其制备方法都具备创新性，未见文献报道。本研究将推进钯膜高效氢分离技术的发展，对于整个和氢气相关的工业领域、以及氢洁净能源的发展有重大影响，具有重要的科学和社会意义。

由于氢气在工业和能源中的重要地位，氢分离纯化一直是工业界和学术界关注的热点。致密超薄钯膜（几个微米厚）可以选择性透过氢，实现氢气廉价高效分离，成为各国研究者关注的重点。目前，钯膜技术面临的一个主要难题是钯膜的化学稳定性问题，即钯膜易中毒（或污染）而失活（或损毁），这使得钯膜难以长期稳定应用。本项目提出了一种钯膜防毒、抗毒的新策略，研究其制备方法及性能机理。该策略在致密钯膜表面制备微孔分子筛膜防毒‘铠甲’，利用微孔分子筛膜小分子筛分特性，使氢气通过而有毒物质通行困难，从而将有毒物质和核心钯膜隔离，实现钯膜防毒、抗毒功能。现有在金属表面制备分子筛膜的方法一般采用金属表面物理磨砂或者化学腐蚀的方法，通过损伤金属表面形成孔洞来固定分子筛，这种方法并不适合于超薄钯膜。本研究提出采用铝钯膜界面扩散无损打桩分子筛连接技术。该技术通过在钯膜上镀纳米铝层，并在合适温度热处理镀铝钯膜，使铝原子扩散渗透到钯膜浅表面层，以此作为连接分子筛和钯膜的根基，经水热过程在钯膜表面上制备连续致密、连接牢固的分子筛膜。分子筛钯膜显示比抗H2S的典型钯基复合膜（Pd-Ag， Pd-Cu等）具有竞争力甚至更好的H2S耐受性，并且由于分子筛微孔道的吸附特性增强了钯膜表面的氢吸附步，从而改变了钯膜表面的透氢速率控制步，增强了氢渗透性。本项目研究的钯膜防毒技术及其制备方法都具备创新性，对于钯膜高效氢分离技术以及分子筛膜制备技术具有重要的科学意义。