The demand for carbon fiber recovery from end-of-life components or carbon fiber waste is increasing with the growing utilization of carbon in many sectors (e. g. automotive, aerospace, etc.). This article presents preliminary investigations processed carbon fibers and semi-finished products made from them. Carbon-reinforced components have already been used for several years. The application of recycled or reused carbon fibers (rCF) in the construction sector, especially to reinforce concrete, offers the possibility to close the material cycle of carbon. The semi-finished products made of rCF investigated in the presented work are intended to represent a first step towards the reuse of carbon fibers in carbon reinforced concrete. To obtain initial information on the properties of the carbon fibers, tests were carried out to determine their tensile strength by investigating yarns and rebars made from recycled carbon fibers. However, a large deviation can be seen in yarns and rebars made from the recycled fibers compared to semi-finished products made from new carbon fibers.