Every year millions of tons of plastic waste are generated worldwide and therefore, certain waste management routes for the reuse, recycling or simply disposal have to be applied. Although there has been a long historical dependency on landfill and waste incineration, new alternative routes for the substantial utilization of plastic wastes are receiving increased attention nowadays. One such promising approach could be the OMV invented solvent based depolymerization process of polyolefin-rich wastes at moderate temperatures, called the ReOil process. This route could finally lead to a feasible way for the chemical recycling of plastics to recover valuable hydrocarbon-rich products which could further be processed in existing refinery facilities. The main focus of this Master’s thesis is on the optimization of the ReOil pilot plant process itself. Test runs were carried out frequently with different feedstock materials (virgin poly-propylene and polyethylene granulate, post-consumer plastic waste), as well as modified process parameters to optimize subsequent test runs by implementing the most recent process adjustments. Additionally, the attained products – mainly comprising a gas, liquid and residue fraction – are analyzed in terms of product quality by identifying organic hydrocarbon compounds and other substances.