Synthesis of Zeolite Crystallites for Diffusion Measurement

该项目的工作致力于确定渗透测量产生的扩散系数(即在固定条件下测量的宏观和介观输运扩散系数)，以便与通过该联盟提供的其他技术获得的可比系统的扩散系数进行比较。此外，对完全卸载膜的渗透实验开始到渗透液突破之间的时间间隔的测量允许在初始瞬变条件下提供相同的信息。考察了尽可能多的参数，包括负载、吸附等温线的形状和温度，以及沸石膜的性质(尺寸、组成)和预处理条件(活化、劣化)的影响。因此，本项目的目的是使用沸石-金属复合膜作为扩散研究的模型膜。嵌入到金属基质中的沸石晶体与财团其他成员在平行扩散研究中使用的沸石材料相同。如果项目1中描述的复合沸石膜的制备成功，我们将有独特的可能性(I)从静态和瞬时渗透实验中得出扩散系数，以及(Ii)预测任何工业沸石膜的预期渗透率，该工业沸石膜最有可能是通过在介孔载体上直接晶化一层沸石而制备的。

The work of this project is devoted to the determination of the diffusivities resulting from permeation measurements (i. e. of macroscopic and mesoscopic transport diffusivities measured under stationary conditions) for comparison with the diffusivities of comparable systems obtained by the other techniques available in the consortium. Moreover, the measurement of the time lag between the start of the permeation experiment with a completely unloaded membrane and the breakthrough of the permeate allows equivalent information under the initial transient conditions. Particular care is given to the investigation of the influence of as many parameters as possible, including loading, shape of the adsorption isotherm and temperature as well as the nature (size, composition) and the pretreatment conditions (activation, deterioration) of the zeolite membrane. It is the aim, therefore, of this project to use the zeolite-in-metal composite membranes as model membranes for diffusion studies. The zeolite crystals embedded into the metal matrix are the identical zeolite materials used in the parallel diffusion studies by the other members of the consortium. Provided that the preparation of the composite zeolite membranes as described in project 1 will be successful, we would have the unique possibility to (i) derive diffusion coefficients from stationary and instationary permeation experiments and to (ii) forecast the expected permeance of any industrial zeolite membrane, which will be most probably prepared by direct crystallization of a thin zeolite layer on a mesoporous support.