Multidimensional fractionation of ultrafine particles in microsystems

微系统中超细颗粒的多维分级

• 批准号: 382122102
• 负责人: Professor Dr. Andreas Dietzel
• 金额: --
• 依托单位: Institut für Partikeltechnik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/382122102?language=en
• 关键词: Multidimensional; fractionation; ultrafine; particles; microsystems

For the production of comparatively high-priced products in various industries, e.g. active pharmaceutical ingredients, ceramics and printable nanoparticle inks, the requirements for particle properties are constantly increasing, with particles in the size range below 10 µm with defined properties increasingly required. Impurities, such as those caused by wear during comminution processes, must also be removed. The necessary multidimensional fractionation of technical suspensions with particles below 10 µm is, however, not satisfactorily possible with state-of-the-art separation methods. Therefore, a microsystem of combined passive and active microelements for multidimensional fractionation with respect to the particle properties size and electrical permittivity shall be developed and investigated in this project. The systems are manufactured by the Institute of Microtechnology using the FLICE process (Femtosecond Laser Irradiation and Chemical Etching) in glass and dry etching (Deep Reactive Ion Etching) in silicon. In the first funding phase, microelements have been developed based on two different principles: the passive Deterministic Lateral Displacement Method (DLD) and (di)electrophoretic forces in (inhomogeneous) electric fields. In the second funding phase, the focus is on integrating the methods into one microsystem. By superposition of the DLD with (inhomogeneous) electric fields, a combined separation according to size and charge or permittivity shall take place. Intensive µPIV investigations as well as coupled CFD-DEM simulations are at the core of the understanding of the multidimensional separation. The influence of the flow velocity and the post shape on the separation result has been investigated so far. The work will be continued in the following, especially with regard to multidimensional separation. The overriding goal of the work, in particular also of the simulations, is the targeted design and layout of the structures with regard to the multidimensional classification of technical suspensions with the highest possible solids content and the highest possible throughput. Together, the two project partners use the findings to produce advanced microelements and combine them into an effective overall system. Due to the wide particle size distribution of real suspensions and the danger of clogging, a further fractionation step has to be integrated on the microchip in order to separate the upper particle size range. Based upon the experimental and simulative results and a deeper understanding of the working principles, models and guidelines for the design of microsystems for technical use are to be developed.

对于各行业中相对高价产品的生产，例如活性药物成分、陶瓷和可印刷纳米颗粒油墨，对颗粒特性的要求不断提高，越来越需要具有规定特性的10 µm以下尺寸范围的颗粒。还必须去除杂质，例如在粉碎过程中由磨损引起的杂质。然而，对于颗粒小于10 µm的技术悬浮液，采用最先进的分离方法无法进行必要的多维分离。因此，在本项目中，应开发和研究一种结合被动和主动微元件的微系统，用于颗粒特性、尺寸和介电常数方面的多维分级。该系统由微技术研究所制造，在玻璃中使用FLICE工艺（飞秒激光照射和化学蚀刻），在硅中使用干法蚀刻（深反应离子蚀刻）。在第一个资助阶段，基于两种不同的原理开发了微型元件：被动确定性侧向位移方法（DLD）和（不均匀）电场中的（双向）电泳力。在第二个供资阶段，重点是将这些方法整合到一个微系统中。通过DLD与（不均匀）电场的叠加，将发生根据尺寸和电荷或介电常数的组合分离。密集的µPIV研究以及耦合的CFD-DEM模拟是理解多维分离的核心。研究了流速和柱体形状对分离效果的影响。今后将继续开展这项工作，特别是在多层面分离方面。这项工作的首要目标，特别是模拟的首要目标，是有针对性地设计和布局结构，以尽可能高的固体含量和尽可能高的吞吐量对技术悬浮液进行多维分类。这两个项目合作伙伴一起使用这些发现来生产先进的微量元素，并将它们联合收割机组合成一个有效的整体系统。由于真实的悬浮液的宽粒度分布和堵塞的危险，必须在微芯片上集成进一步的分级步骤，以分离较高的粒度范围。基于实验和模拟结果以及对工作原理的更深入理解，将开发用于技术用途的微系统设计的模型和指南。