Since the demand for platinum has overtaken primary metallurgys supply in the last years the demand was partially met from stocks. Therefore platinum recycling efforts have to be enforced and new recycling concepts have to be found. One promising way is a newly developed hydrometallurgical process for leaching the precious metal depletion of catalysts with ceramic carriers. The success of the leaching significantly depends on the upstream thermal treatment step, which had to be optimized within the scope of this thesis. A main object in this context was to find the optimal evaporation conditions of the volatile compounds (C, CxHy, etc.) contaminating the spent catalysts. At the same time a change in phase modification of the ceramic material during the thermal treatment had to be avoided. Investigations were carried out with a rotary kiln in laboratory scale as well as with simultaneous thermal analysis (STA). With respect to economical concerns it was a requirement that an overall platinum recovery of more than 98 % could be achieved with this process.