The size fractionation of magnetic nanoparticles is a technical problem, which until today can only be solved with great effort. Nevertheless, there is an important demand for nanoparticles with sharp size distributions, for example for medical technology or sensor technology. Using magnetic chromatography, we show a promising method for fractionation of magnetic nanoparticles with respect to their size and/or magnetic properties. This was achieved by passing magnetic nanoparticles through a packed bed of fine steel spheres with which they interact magnetically because single domain ferro-/ferrimagnetic nanoparticles show a spontaneous magnetization. Since the strength of this interaction is related to particle size, the principle is suitable for size fractionation. This concept was transferred into a continuous process in this work using a so-called simulated moving bed chromatography. Applying a suspension of magnetic nanoparticles within a size range from 20 to 120 nm, the process showed a separation sharpness of up to 0.52 with recovery rates of 100%. The continuous feed stream of magnetic nanoparticles could be fractionated with a space-time-yield of up to 5 mg/(L·min). Due to the easy scalability of continuous chromatography, the process is a promising approach for the efficient fractionation of industrially relevant amounts of magnetic nanoparticles.

磁性纳米粒子的尺寸分级是一个技术问题，直到今天，这仍然需要付出很大的努力才能解决。然而，对于例如用于医疗技术或传感器技术的具有锐利的尺寸分布的纳米颗粒存在重要的需求。使用磁性色谱，我们展示了一种有前途的方法，可用于分离磁性纳米粒子的大小和/或磁性。这是通过使磁性纳米粒子穿过细钢球的填充床而实现的，因为单畴铁/亚铁磁性纳米粒子表现出自发的磁化作用，因此与磁性粒子相互作用。由于这种相互作用的强度与粒度有关，因此该原理适用于粒度分级。使用所谓的模拟移动床色谱法将该概念转化为这项工作的连续过程。应用尺寸为20至120 nm的磁性纳米颗粒悬浮液，该工艺显示分离锐度高达0.52，回收率为100％。磁性纳米颗粒的连续进料流可以以高达5 mg /（L·min）的时空产率进行分馏。由于连续色谱法易于扩展，该方法是有效分离工业上相关量的磁性纳米粒子的一种有前途的方法。磁性纳米颗粒的连续进料流可以以高达5 mg /（L·min）的时空产率进行分馏。由于连续色谱法易于扩展，该方法是有效分离工业上相关量的磁性纳米粒子的一种有前途的方法。磁性纳米颗粒的连续进料流可以以高达5 mg /（L·min）的时空产率进行分馏。由于连续色谱法易于扩展，该方法是有效分离工业上相关量的磁性纳米粒子的一种有前途的方法。