In modern high-performance agriculture, the focus on clean fields increases. Due to herbicide resistant weeds, political pressure and public interest alternative, non-chemical procedures are gaining a new relevance in weed control. One possible approach is the separation of weed seeds in combine harvesters in order to prevent the distribution of weed seeds back to the fields. Objective is to develop a weed seed separation device in cooperation with industry partners as a retrofit or OEM kit for combine harvesters and plot combines.Two methods to separate weed seeds in combine harvesters are tested. On the one hand, a vibro-fluidization system is evaluated, and on the other hand a system that uses the deflecting properties of particles is investigated. The tests are carried out with different parameters to find the optimal settings for the separation process. Under lab conditions, up to 65 % of the weed seeds could be separated by using the deflecting properties and up to 95 % by vibro-fluidization.