Abstract: The proposed spinning disc reactor comprises substantially a horizontally rotatable, disc-like and thermostatable support element which has an outer reaction surface, feed means for feeding at least one reactant onto the reaction surface and internal structures for thermostating the reaction surface. In addition, it contains at least one separation apparatus for collecting and removing the reaction product from the reaction surface. The support element is characterized in particular in that it consists of two components a) and b) arranged horizontally one on top of the other and having substantially identical surface measures. These two components are connected to one another in an interlocking manner and tightly during the operating time and the lower component a) has, on its top facing the inner region of the support element, at least one substantially uninterrupted groove milled in over an extensive area and intended for receiving, conducting and discharging a heat-transfer fluid.